Improve code quality and write tests

node_modules/regexp-tree/LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2017 Dmitry Soshnikov
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

node_modules/regexp-tree/bin/regexp-tree

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+#!/usr/bin/env node
+
+'use strict';
+
+require('../dist/bin/regexp-tree')();

node_modules/regexp-tree/dist/bin/regexp-tree.js

@@ -0,0 +1,16 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+function main() {
+  console.info('\n  =========================================================\n  * CLI commands are moved to the \x1B[1mregexp-tree-cli\x1B[0m package *\n  =========================================================\n\n  \x1B[1mInstallation:\x1B[0m\n\n    npm install -g regexp-tree-cli\n\n  \x1B[1mUsage:\x1B[0m\n\n    regexp-tree-cli --help\n  ');
+}
+
+module.exports = main;
+
+if (require.main === module) {
+  main();
+}

node_modules/regexp-tree/dist/compat-transpiler/index.js

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+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+var compatTransforms = require('./transforms');
+var _transform = require('../transform');
+
+module.exports = {
+  /**
+   * Translates a regexp in new syntax to equivalent regexp in old syntax.
+   *
+   * @param string|RegExp|AST - regexp
+   * @param Array transformsWhitelist - names of the transforms to apply
+   */
+  transform: function transform(regexp) {
+    var transformsWhitelist = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : [];
+
+    var transformToApply = transformsWhitelist.length > 0 ? transformsWhitelist : Object.keys(compatTransforms);
+
+    var result = void 0;
+
+    // Collect extra data per transform.
+    var extra = {};
+
+    transformToApply.forEach(function (transformName) {
+
+      if (!compatTransforms.hasOwnProperty(transformName)) {
+        throw new Error('Unknown compat-transform: ' + transformName + '. ' + 'Available transforms are: ' + Object.keys(compatTransforms).join(', '));
+      }
+
+      var handler = compatTransforms[transformName];
+
+      result = _transform.transform(regexp, handler);
+      regexp = result.getAST();
+
+      // Collect `extra` transform result.
+      if (typeof handler.getExtra === 'function') {
+        extra[transformName] = handler.getExtra();
+      }
+    });
+
+    // Set the final extras for all transforms.
+    result.setExtra(extra);
+
+    return result;
+  }
+};

node_modules/regexp-tree/dist/compat-transpiler/runtime/index.js

@@ -0,0 +1,123 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+/**
+ * The `RegExpTree` class provides runtime support for `compat-transpiler`
+ * module from `regexp-tree`.
+ *
+ * E.g. it tracks names of the capturing groups, in order to access the
+ * names on the matched result.
+ *
+ * It's a thin-wrapper on top of original regexp.
+ */
+
+var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();
+
+function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
+
+var RegExpTree = function () {
+  /**
+   * Initializes a `RegExpTree` instance.
+   *
+   * @param RegExp - a regular expression
+   *
+   * @param Object state:
+   *
+   *   An extra state which may store any related to transformation
+   *   data, for example, names of the groups.
+   *
+   *   - flags - original flags
+   *   - groups - names of the groups, and their indices
+   *   - source - original source
+   */
+  function RegExpTree(re, _ref) {
+    var flags = _ref.flags,
+        groups = _ref.groups,
+        source = _ref.source;
+
+    _classCallCheck(this, RegExpTree);
+
+    this._re = re;
+    this._groups = groups;
+
+    // Original props.
+    this.flags = flags;
+    this.source = source || re.source;
+    this.dotAll = flags.includes('s');
+
+    // Inherited directly from `re`.
+    this.global = re.global;
+    this.ignoreCase = re.ignoreCase;
+    this.multiline = re.multiline;
+    this.sticky = re.sticky;
+    this.unicode = re.unicode;
+  }
+
+  /**
+   * Facade wrapper for RegExp `test` method.
+   */
+
+
+  _createClass(RegExpTree, [{
+    key: 'test',
+    value: function test(string) {
+      return this._re.test(string);
+    }
+
+    /**
+     * Facade wrapper for RegExp `compile` method.
+     */
+
+  }, {
+    key: 'compile',
+    value: function compile(string) {
+      return this._re.compile(string);
+    }
+
+    /**
+     * Facade wrapper for RegExp `toString` method.
+     */
+
+  }, {
+    key: 'toString',
+    value: function toString() {
+      if (!this._toStringResult) {
+        this._toStringResult = '/' + this.source + '/' + this.flags;
+      }
+      return this._toStringResult;
+    }
+
+    /**
+     * Facade wrapper for RegExp `exec` method.
+     */
+
+  }, {
+    key: 'exec',
+    value: function exec(string) {
+      var result = this._re.exec(string);
+
+      if (!this._groups || !result) {
+        return result;
+      }
+
+      result.groups = {};
+
+      for (var group in this._groups) {
+        var groupNumber = this._groups[group];
+        result.groups[group] = result[groupNumber];
+      }
+
+      return result;
+    }
+  }]);
+
+  return RegExpTree;
+}();
+
+module.exports = {
+  RegExpTree: RegExpTree
+};

node_modules/regexp-tree/dist/compat-transpiler/transforms/compat-dotall-s-transform.js

@@ -0,0 +1,69 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+/**
+ * A regexp-tree plugin to translate `/./s` to `/[\0-\uFFFF]/`.
+ */
+
+module.exports = {
+
+  // Whether `u` flag present. In which case we transform to
+  // \u{10FFFF} instead of \uFFFF.
+  _hasUFlag: false,
+
+  // Only run this plugin if we have `s` flag.
+  shouldRun: function shouldRun(ast) {
+    var shouldRun = ast.flags.includes('s');
+
+    if (!shouldRun) {
+      return false;
+    }
+
+    // Strip the `s` flag.
+    ast.flags = ast.flags.replace('s', '');
+
+    // Whether we have also `u`.
+    this._hasUFlag = ast.flags.includes('u');
+
+    return true;
+  },
+  Char: function Char(path) {
+    var node = path.node;
+
+
+    if (node.kind !== 'meta' || node.value !== '.') {
+      return;
+    }
+
+    var toValue = '\\uFFFF';
+    var toSymbol = '\uFFFF';
+
+    if (this._hasUFlag) {
+      toValue = '\\u{10FFFF}';
+      toSymbol = '\uDBFF\uDFFF';
+    }
+
+    path.replace({
+      type: 'CharacterClass',
+      expressions: [{
+        type: 'ClassRange',
+        from: {
+          type: 'Char',
+          value: '\\0',
+          kind: 'decimal',
+          symbol: '\0'
+        },
+        to: {
+          type: 'Char',
+          value: toValue,
+          kind: 'unicode',
+          symbol: toSymbol
+        }
+      }]
+    });
+  }
+};

node_modules/regexp-tree/dist/compat-transpiler/transforms/compat-named-capturing-groups-transform.js

@@ -0,0 +1,59 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+/**
+ * A regexp-tree plugin to translate `/(?<name>a)\k<name>/` to `/(a)\1/`.
+ */
+
+module.exports = {
+  // To track the names of the groups, and return them
+  // in the transform result state.
+  //
+  // A map from name to number: {foo: 2, bar: 4}
+  _groupNames: {},
+
+  /**
+   * Initialises the trasnform.
+   */
+  init: function init() {
+    this._groupNames = {};
+  },
+
+
+  /**
+   * Returns extra state, which eventually is returned to
+   */
+  getExtra: function getExtra() {
+    return this._groupNames;
+  },
+  Group: function Group(path) {
+    var node = path.node;
+
+
+    if (!node.name) {
+      return;
+    }
+
+    // Record group name.
+    this._groupNames[node.name] = node.number;
+
+    delete node.name;
+    delete node.nameRaw;
+  },
+  Backreference: function Backreference(path) {
+    var node = path.node;
+
+
+    if (node.kind !== 'name') {
+      return;
+    }
+
+    node.kind = 'number';
+    node.reference = node.number;
+    delete node.referenceRaw;
+  }
+};

node_modules/regexp-tree/dist/compat-transpiler/transforms/compat-x-flag-transform.js

@@ -0,0 +1,23 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+/**
+ * A regexp-tree plugin to remove `x` flag `/foo/x` to `/foo/`.
+ *
+ * Note: other features of `x` flags (whitespace, comments) are
+ * already removed at parsing stage.
+ */
+
+module.exports = {
+  RegExp: function RegExp(_ref) {
+    var node = _ref.node;
+
+    if (node.flags.includes('x')) {
+      node.flags = node.flags.replace('x', '');
+    }
+  }
+};

node_modules/regexp-tree/dist/compat-transpiler/transforms/index.js

@@ -0,0 +1,17 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+module.exports = {
+  // "dotAll" `s` flag
+  dotAll: require('./compat-dotall-s-transform'),
+
+  // Named capturing groups.
+  namedCapturingGroups: require('./compat-named-capturing-groups-transform'),
+
+  // `x` flag
+  xFlag: require('./compat-x-flag-transform')
+};

node_modules/regexp-tree/dist/generator/index.js

@@ -0,0 +1,177 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+/**
+ * Helper `gen` function calls node type handler.
+ */
+
+function gen(node) {
+  return node ? generator[node.type](node) : '';
+}
+
+/**
+ * AST handler.
+ */
+var generator = {
+  RegExp: function RegExp(node) {
+    return '/' + gen(node.body) + '/' + node.flags;
+  },
+  Alternative: function Alternative(node) {
+    return (node.expressions || []).map(gen).join('');
+  },
+  Disjunction: function Disjunction(node) {
+    return gen(node.left) + '|' + gen(node.right);
+  },
+  Group: function Group(node) {
+    var expression = gen(node.expression);
+
+    if (node.capturing) {
+      // A named group.
+      if (node.name) {
+        return '(?<' + (node.nameRaw || node.name) + '>' + expression + ')';
+      }
+
+      return '(' + expression + ')';
+    }
+
+    return '(?:' + expression + ')';
+  },
+  Backreference: function Backreference(node) {
+    switch (node.kind) {
+      case 'number':
+        return '\\' + node.reference;
+      case 'name':
+        return '\\k<' + (node.referenceRaw || node.reference) + '>';
+      default:
+        throw new TypeError('Unknown Backreference kind: ' + node.kind);
+    }
+  },
+  Assertion: function Assertion(node) {
+    switch (node.kind) {
+      case '^':
+      case '$':
+      case '\\b':
+      case '\\B':
+        return node.kind;
+
+      case 'Lookahead':
+        {
+          var assertion = gen(node.assertion);
+
+          if (node.negative) {
+            return '(?!' + assertion + ')';
+          }
+
+          return '(?=' + assertion + ')';
+        }
+
+      case 'Lookbehind':
+        {
+          var _assertion = gen(node.assertion);
+
+          if (node.negative) {
+            return '(?<!' + _assertion + ')';
+          }
+
+          return '(?<=' + _assertion + ')';
+        }
+
+      default:
+        throw new TypeError('Unknown Assertion kind: ' + node.kind);
+    }
+  },
+  CharacterClass: function CharacterClass(node) {
+    var expressions = node.expressions.map(gen).join('');
+
+    if (node.negative) {
+      return '[^' + expressions + ']';
+    }
+
+    return '[' + expressions + ']';
+  },
+  ClassRange: function ClassRange(node) {
+    return gen(node.from) + '-' + gen(node.to);
+  },
+  Repetition: function Repetition(node) {
+    return '' + gen(node.expression) + gen(node.quantifier);
+  },
+  Quantifier: function Quantifier(node) {
+    var quantifier = void 0;
+    var greedy = node.greedy ? '' : '?';
+
+    switch (node.kind) {
+      case '+':
+      case '?':
+      case '*':
+        quantifier = node.kind;
+        break;
+      case 'Range':
+        // Exact: {1}
+        if (node.from === node.to) {
+          quantifier = '{' + node.from + '}';
+        }
+        // Open: {1,}
+        else if (!node.to) {
+            quantifier = '{' + node.from + ',}';
+          }
+          // Closed: {1,3}
+          else {
+              quantifier = '{' + node.from + ',' + node.to + '}';
+            }
+        break;
+      default:
+        throw new TypeError('Unknown Quantifier kind: ' + node.kind);
+    }
+
+    return '' + quantifier + greedy;
+  },
+  Char: function Char(node) {
+    var value = node.value;
+
+    switch (node.kind) {
+      case 'simple':
+        {
+          if (node.escaped) {
+            return '\\' + value;
+          }
+          return value;
+        }
+
+      case 'hex':
+      case 'unicode':
+      case 'oct':
+      case 'decimal':
+      case 'control':
+      case 'meta':
+        return value;
+
+      default:
+        throw new TypeError('Unknown Char kind: ' + node.kind);
+    }
+  },
+  UnicodeProperty: function UnicodeProperty(node) {
+    var escapeChar = node.negative ? 'P' : 'p';
+    var namePart = void 0;
+
+    if (!node.shorthand && !node.binary) {
+      namePart = node.name + '=';
+    } else {
+      namePart = '';
+    }
+
+    return '\\' + escapeChar + '{' + namePart + node.value + '}';
+  }
+};
+
+module.exports = {
+  /**
+   * Generates a regexp string from an AST.
+   *
+   * @param Object ast - an AST node
+   */
+  generate: gen
+};

node_modules/regexp-tree/dist/interpreter/finite-automaton/dfa/dfa-minimizer.js

@@ -0,0 +1,412 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+// DFA minization.
+
+/**
+ * Map from state to current set it goes.
+ */
+
+var _slicedToArray = function () { function sliceIterator(arr, i) { var _arr = []; var _n = true; var _d = false; var _e = undefined; try { for (var _i = arr[Symbol.iterator](), _s; !(_n = (_s = _i.next()).done); _n = true) { _arr.push(_s.value); if (i && _arr.length === i) break; } } catch (err) { _d = true; _e = err; } finally { try { if (!_n && _i["return"]) _i["return"](); } finally { if (_d) throw _e; } } return _arr; } return function (arr, i) { if (Array.isArray(arr)) { return arr; } else if (Symbol.iterator in Object(arr)) { return sliceIterator(arr, i); } else { throw new TypeError("Invalid attempt to destructure non-iterable instance"); } }; }();
+
+function _toArray(arr) { return Array.isArray(arr) ? arr : Array.from(arr); }
+
+function _toConsumableArray(arr) { if (Array.isArray(arr)) { for (var i = 0, arr2 = Array(arr.length); i < arr.length; i++) { arr2[i] = arr[i]; } return arr2; } else { return Array.from(arr); } }
+
+var currentTransitionMap = null;
+
+/**
+ * Takes a DFA, and returns a minimized version of it
+ * compressing some states to groups (using standard, 0-, 1-,
+ * 2-, ... N-equivalence algorithm).
+ */
+function minimize(dfa) {
+  var table = dfa.getTransitionTable();
+  var allStates = Object.keys(table);
+  var alphabet = dfa.getAlphabet();
+  var accepting = dfa.getAcceptingStateNumbers();
+
+  currentTransitionMap = {};
+
+  var nonAccepting = new Set();
+
+  allStates.forEach(function (state) {
+    state = Number(state);
+    var isAccepting = accepting.has(state);
+
+    if (isAccepting) {
+      currentTransitionMap[state] = accepting;
+    } else {
+      nonAccepting.add(state);
+      currentTransitionMap[state] = nonAccepting;
+    }
+  });
+
+  // ---------------------------------------------------------------------------
+  // Step 1: build equivalent sets.
+
+  // All [1..N] equivalent sets.
+  var all = [
+  // 0-equivalent sets.
+  [nonAccepting, accepting].filter(function (set) {
+    return set.size > 0;
+  })];
+
+  var current = void 0;
+  var previous = void 0;
+
+  // Top of the stack is the current list of sets to analyze.
+  current = all[all.length - 1];
+
+  // Previous set (to check whether we need to stop).
+  previous = all[all.length - 2];
+
+  // Until we'll not have the same N and N-1 equivalent rows.
+
+  var _loop = function _loop() {
+    var newTransitionMap = {};
+
+    var _iteratorNormalCompletion3 = true;
+    var _didIteratorError3 = false;
+    var _iteratorError3 = undefined;
+
+    try {
+      for (var _iterator3 = current[Symbol.iterator](), _step3; !(_iteratorNormalCompletion3 = (_step3 = _iterator3.next()).done); _iteratorNormalCompletion3 = true) {
+        var _set = _step3.value;
+
+        // Handled states for this set.
+        var handledStates = {};
+
+        var _set2 = _toArray(_set),
+            first = _set2[0],
+            rest = _set2.slice(1);
+
+        handledStates[first] = new Set([first]);
+
+        // Have to compare each from the rest states with
+        // the already handled states, and see if they are equivalent.
+        var _iteratorNormalCompletion4 = true;
+        var _didIteratorError4 = false;
+        var _iteratorError4 = undefined;
+
+        try {
+          restSets: for (var _iterator4 = rest[Symbol.iterator](), _step4; !(_iteratorNormalCompletion4 = (_step4 = _iterator4.next()).done); _iteratorNormalCompletion4 = true) {
+            var state = _step4.value;
+            var _iteratorNormalCompletion5 = true;
+            var _didIteratorError5 = false;
+            var _iteratorError5 = undefined;
+
+            try {
+              for (var _iterator5 = Object.keys(handledStates)[Symbol.iterator](), _step5; !(_iteratorNormalCompletion5 = (_step5 = _iterator5.next()).done); _iteratorNormalCompletion5 = true) {
+                var handledState = _step5.value;
+
+                // This and some previously handled state are equivalent --
+                // just append this state to the same set.
+                if (areEquivalent(state, handledState, table, alphabet)) {
+                  handledStates[handledState].add(state);
+                  handledStates[state] = handledStates[handledState];
+                  continue restSets;
+                }
+              }
+              // Else, this state is not equivalent to any of the
+              // handled states -- allocate a new set for it.
+            } catch (err) {
+              _didIteratorError5 = true;
+              _iteratorError5 = err;
+            } finally {
+              try {
+                if (!_iteratorNormalCompletion5 && _iterator5.return) {
+                  _iterator5.return();
+                }
+              } finally {
+                if (_didIteratorError5) {
+                  throw _iteratorError5;
+                }
+              }
+            }
+
+            handledStates[state] = new Set([state]);
+          }
+        } catch (err) {
+          _didIteratorError4 = true;
+          _iteratorError4 = err;
+        } finally {
+          try {
+            if (!_iteratorNormalCompletion4 && _iterator4.return) {
+              _iterator4.return();
+            }
+          } finally {
+            if (_didIteratorError4) {
+              throw _iteratorError4;
+            }
+          }
+        }
+
+        // Add these handled states to all states map.
+
+
+        Object.assign(newTransitionMap, handledStates);
+      }
+
+      // Update current transition map for the handled row.
+    } catch (err) {
+      _didIteratorError3 = true;
+      _iteratorError3 = err;
+    } finally {
+      try {
+        if (!_iteratorNormalCompletion3 && _iterator3.return) {
+          _iterator3.return();
+        }
+      } finally {
+        if (_didIteratorError3) {
+          throw _iteratorError3;
+        }
+      }
+    }
+
+    currentTransitionMap = newTransitionMap;
+
+    var newSets = new Set(Object.keys(newTransitionMap).map(function (state) {
+      return newTransitionMap[state];
+    }));
+
+    all.push([].concat(_toConsumableArray(newSets)));
+
+    // Top of the stack is the current.
+    current = all[all.length - 1];
+
+    // Previous set.
+    previous = all[all.length - 2];
+  };
+
+  while (!sameRow(current, previous)) {
+    _loop();
+  }
+
+  // ---------------------------------------------------------------------------
+  // Step 2: build minimized table from the equivalent sets.
+
+  // Remap state numbers from sets to index-based.
+  var remaped = new Map();
+  var idx = 1;
+  current.forEach(function (set) {
+    return remaped.set(set, idx++);
+  });
+
+  // Build the minimized table from the calculated equivalent sets.
+  var minimizedTable = {};
+
+  var minimizedAcceptingStates = new Set();
+
+  var updateAcceptingStates = function updateAcceptingStates(set, idx) {
+    var _iteratorNormalCompletion = true;
+    var _didIteratorError = false;
+    var _iteratorError = undefined;
+
+    try {
+      for (var _iterator = set[Symbol.iterator](), _step; !(_iteratorNormalCompletion = (_step = _iterator.next()).done); _iteratorNormalCompletion = true) {
+        var state = _step.value;
+
+        if (accepting.has(state)) {
+          minimizedAcceptingStates.add(idx);
+        }
+      }
+    } catch (err) {
+      _didIteratorError = true;
+      _iteratorError = err;
+    } finally {
+      try {
+        if (!_iteratorNormalCompletion && _iterator.return) {
+          _iterator.return();
+        }
+      } finally {
+        if (_didIteratorError) {
+          throw _iteratorError;
+        }
+      }
+    }
+  };
+
+  var _iteratorNormalCompletion2 = true;
+  var _didIteratorError2 = false;
+  var _iteratorError2 = undefined;
+
+  try {
+    for (var _iterator2 = remaped.entries()[Symbol.iterator](), _step2; !(_iteratorNormalCompletion2 = (_step2 = _iterator2.next()).done); _iteratorNormalCompletion2 = true) {
+      var _ref = _step2.value;
+
+      var _ref2 = _slicedToArray(_ref, 2);
+
+      var set = _ref2[0];
+      var _idx = _ref2[1];
+
+      minimizedTable[_idx] = {};
+      var _iteratorNormalCompletion6 = true;
+      var _didIteratorError6 = false;
+      var _iteratorError6 = undefined;
+
+      try {
+        for (var _iterator6 = alphabet[Symbol.iterator](), _step6; !(_iteratorNormalCompletion6 = (_step6 = _iterator6.next()).done); _iteratorNormalCompletion6 = true) {
+          var symbol = _step6.value;
+
+          updateAcceptingStates(set, _idx);
+
+          // Determine original transition for this symbol from the set.
+          var originalTransition = void 0;
+          var _iteratorNormalCompletion7 = true;
+          var _didIteratorError7 = false;
+          var _iteratorError7 = undefined;
+
+          try {
+            for (var _iterator7 = set[Symbol.iterator](), _step7; !(_iteratorNormalCompletion7 = (_step7 = _iterator7.next()).done); _iteratorNormalCompletion7 = true) {
+              var originalState = _step7.value;
+
+              originalTransition = table[originalState][symbol];
+              if (originalTransition) {
+                break;
+              }
+            }
+          } catch (err) {
+            _didIteratorError7 = true;
+            _iteratorError7 = err;
+          } finally {
+            try {
+              if (!_iteratorNormalCompletion7 && _iterator7.return) {
+                _iterator7.return();
+              }
+            } finally {
+              if (_didIteratorError7) {
+                throw _iteratorError7;
+              }
+            }
+          }
+
+          if (originalTransition) {
+            minimizedTable[_idx][symbol] = remaped.get(currentTransitionMap[originalTransition]);
+          }
+        }
+      } catch (err) {
+        _didIteratorError6 = true;
+        _iteratorError6 = err;
+      } finally {
+        try {
+          if (!_iteratorNormalCompletion6 && _iterator6.return) {
+            _iterator6.return();
+          }
+        } finally {
+          if (_didIteratorError6) {
+            throw _iteratorError6;
+          }
+        }
+      }
+    }
+
+    // Update the table, and accepting states on the original DFA.
+  } catch (err) {
+    _didIteratorError2 = true;
+    _iteratorError2 = err;
+  } finally {
+    try {
+      if (!_iteratorNormalCompletion2 && _iterator2.return) {
+        _iterator2.return();
+      }
+    } finally {
+      if (_didIteratorError2) {
+        throw _iteratorError2;
+      }
+    }
+  }
+
+  dfa.setTransitionTable(minimizedTable);
+  dfa.setAcceptingStateNumbers(minimizedAcceptingStates);
+
+  return dfa;
+}
+
+function sameRow(r1, r2) {
+  if (!r2) {
+    return false;
+  }
+
+  if (r1.length !== r2.length) {
+    return false;
+  }
+
+  for (var i = 0; i < r1.length; i++) {
+    var s1 = r1[i];
+    var s2 = r2[i];
+
+    if (s1.size !== s2.size) {
+      return false;
+    }
+
+    if ([].concat(_toConsumableArray(s1)).sort().join(',') !== [].concat(_toConsumableArray(s2)).sort().join(',')) {
+      return false;
+    }
+  }
+
+  return true;
+}
+
+/**
+ * Checks whether two states are N-equivalent, i.e. whether they go
+ * to the same set on a symbol.
+ */
+function areEquivalent(s1, s2, table, alphabet) {
+  var _iteratorNormalCompletion8 = true;
+  var _didIteratorError8 = false;
+  var _iteratorError8 = undefined;
+
+  try {
+    for (var _iterator8 = alphabet[Symbol.iterator](), _step8; !(_iteratorNormalCompletion8 = (_step8 = _iterator8.next()).done); _iteratorNormalCompletion8 = true) {
+      var symbol = _step8.value;
+
+      if (!goToSameSet(s1, s2, table, symbol)) {
+        return false;
+      }
+    }
+  } catch (err) {
+    _didIteratorError8 = true;
+    _iteratorError8 = err;
+  } finally {
+    try {
+      if (!_iteratorNormalCompletion8 && _iterator8.return) {
+        _iterator8.return();
+      }
+    } finally {
+      if (_didIteratorError8) {
+        throw _iteratorError8;
+      }
+    }
+  }
+
+  return true;
+}
+
+/**
+ * Checks whether states go to the same set.
+ */
+function goToSameSet(s1, s2, table, symbol) {
+  if (!currentTransitionMap[s1] || !currentTransitionMap[s2]) {
+    return false;
+  }
+
+  var originalTransitionS1 = table[s1][symbol];
+  var originalTransitionS2 = table[s2][symbol];
+
+  // If no actual transition on this symbol, treat it as positive.
+  if (!originalTransitionS1 && !originalTransitionS2) {
+    return true;
+  }
+
+  // Otherwise, check if they are in the same sets.
+  return currentTransitionMap[s1].has(originalTransitionS1) && currentTransitionMap[s2].has(originalTransitionS2);
+}
+
+module.exports = {
+  minimize: minimize
+};

node_modules/regexp-tree/dist/interpreter/finite-automaton/dfa/dfa.js

@@ -0,0 +1,380 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();
+
+function _toConsumableArray(arr) { if (Array.isArray(arr)) { for (var i = 0, arr2 = Array(arr.length); i < arr.length; i++) { arr2[i] = arr[i]; } return arr2; } else { return Array.from(arr); } }
+
+function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
+
+var DFAMinimizer = require('./dfa-minimizer');
+
+var _require = require('../special-symbols'),
+    EPSILON_CLOSURE = _require.EPSILON_CLOSURE;
+
+/**
+ * DFA is build by converting from NFA (subset construction).
+ */
+
+
+var DFA = function () {
+  function DFA(nfa) {
+    _classCallCheck(this, DFA);
+
+    this._nfa = nfa;
+  }
+
+  /**
+   * Minimizes DFA.
+   */
+
+
+  _createClass(DFA, [{
+    key: 'minimize',
+    value: function minimize() {
+      this.getTransitionTable();
+
+      this._originalAcceptingStateNumbers = this._acceptingStateNumbers;
+      this._originalTransitionTable = this._transitionTable;
+
+      DFAMinimizer.minimize(this);
+    }
+
+    /**
+     * Returns alphabet for this DFA.
+     */
+
+  }, {
+    key: 'getAlphabet',
+    value: function getAlphabet() {
+      return this._nfa.getAlphabet();
+    }
+
+    /**
+     * Returns accepting states.
+     */
+
+  }, {
+    key: 'getAcceptingStateNumbers',
+    value: function getAcceptingStateNumbers() {
+      if (!this._acceptingStateNumbers) {
+        // Accepting states are determined during table construction.
+        this.getTransitionTable();
+      }
+
+      return this._acceptingStateNumbers;
+    }
+
+    /**
+     * Returns original accepting states.
+     */
+
+  }, {
+    key: 'getOriginaAcceptingStateNumbers',
+    value: function getOriginaAcceptingStateNumbers() {
+      if (!this._originalAcceptingStateNumbers) {
+        // Accepting states are determined during table construction.
+        this.getTransitionTable();
+      }
+
+      return this._originalAcceptingStateNumbers;
+    }
+
+    /**
+     * Sets transition table.
+     */
+
+  }, {
+    key: 'setTransitionTable',
+    value: function setTransitionTable(table) {
+      this._transitionTable = table;
+    }
+
+    /**
+     * Sets accepting states.
+     */
+
+  }, {
+    key: 'setAcceptingStateNumbers',
+    value: function setAcceptingStateNumbers(stateNumbers) {
+      this._acceptingStateNumbers = stateNumbers;
+    }
+
+    /**
+     * DFA transition table is built from NFA table.
+     */
+
+  }, {
+    key: 'getTransitionTable',
+    value: function getTransitionTable() {
+      var _this = this;
+
+      if (this._transitionTable) {
+        return this._transitionTable;
+      }
+
+      // Calculate from NFA transition table.
+      var nfaTable = this._nfa.getTransitionTable();
+      var nfaStates = Object.keys(nfaTable);
+
+      this._acceptingStateNumbers = new Set();
+
+      // Start state of DFA is E(S[nfa])
+      var startState = nfaTable[nfaStates[0]][EPSILON_CLOSURE];
+
+      // Init the worklist (states which should be in the DFA).
+      var worklist = [startState];
+
+      var alphabet = this.getAlphabet();
+      var nfaAcceptingStates = this._nfa.getAcceptingStateNumbers();
+
+      var dfaTable = {};
+
+      // Determine whether the combined DFA state is accepting.
+      var updateAcceptingStates = function updateAcceptingStates(states) {
+        var _iteratorNormalCompletion = true;
+        var _didIteratorError = false;
+        var _iteratorError = undefined;
+
+        try {
+          for (var _iterator = nfaAcceptingStates[Symbol.iterator](), _step; !(_iteratorNormalCompletion = (_step = _iterator.next()).done); _iteratorNormalCompletion = true) {
+            var nfaAcceptingState = _step.value;
+
+            // If any of the states from NFA is accepting, DFA's
+            // state is accepting as well.
+            if (states.indexOf(nfaAcceptingState) !== -1) {
+              _this._acceptingStateNumbers.add(states.join(','));
+              break;
+            }
+          }
+        } catch (err) {
+          _didIteratorError = true;
+          _iteratorError = err;
+        } finally {
+          try {
+            if (!_iteratorNormalCompletion && _iterator.return) {
+              _iterator.return();
+            }
+          } finally {
+            if (_didIteratorError) {
+              throw _iteratorError;
+            }
+          }
+        }
+      };
+
+      while (worklist.length > 0) {
+        var states = worklist.shift();
+        var dfaStateLabel = states.join(',');
+        dfaTable[dfaStateLabel] = {};
+
+        var _iteratorNormalCompletion2 = true;
+        var _didIteratorError2 = false;
+        var _iteratorError2 = undefined;
+
+        try {
+          for (var _iterator2 = alphabet[Symbol.iterator](), _step2; !(_iteratorNormalCompletion2 = (_step2 = _iterator2.next()).done); _iteratorNormalCompletion2 = true) {
+            var symbol = _step2.value;
+
+            var onSymbol = [];
+
+            // Determine whether the combined state is accepting.
+            updateAcceptingStates(states);
+
+            var _iteratorNormalCompletion3 = true;
+            var _didIteratorError3 = false;
+            var _iteratorError3 = undefined;
+
+            try {
+              for (var _iterator3 = states[Symbol.iterator](), _step3; !(_iteratorNormalCompletion3 = (_step3 = _iterator3.next()).done); _iteratorNormalCompletion3 = true) {
+                var state = _step3.value;
+
+                var nfaStatesOnSymbol = nfaTable[state][symbol];
+                if (!nfaStatesOnSymbol) {
+                  continue;
+                }
+
+                var _iteratorNormalCompletion4 = true;
+                var _didIteratorError4 = false;
+                var _iteratorError4 = undefined;
+
+                try {
+                  for (var _iterator4 = nfaStatesOnSymbol[Symbol.iterator](), _step4; !(_iteratorNormalCompletion4 = (_step4 = _iterator4.next()).done); _iteratorNormalCompletion4 = true) {
+                    var nfaStateOnSymbol = _step4.value;
+
+                    if (!nfaTable[nfaStateOnSymbol]) {
+                      continue;
+                    }
+                    onSymbol.push.apply(onSymbol, _toConsumableArray(nfaTable[nfaStateOnSymbol][EPSILON_CLOSURE]));
+                  }
+                } catch (err) {
+                  _didIteratorError4 = true;
+                  _iteratorError4 = err;
+                } finally {
+                  try {
+                    if (!_iteratorNormalCompletion4 && _iterator4.return) {
+                      _iterator4.return();
+                    }
+                  } finally {
+                    if (_didIteratorError4) {
+                      throw _iteratorError4;
+                    }
+                  }
+                }
+              }
+            } catch (err) {
+              _didIteratorError3 = true;
+              _iteratorError3 = err;
+            } finally {
+              try {
+                if (!_iteratorNormalCompletion3 && _iterator3.return) {
+                  _iterator3.return();
+                }
+              } finally {
+                if (_didIteratorError3) {
+                  throw _iteratorError3;
+                }
+              }
+            }
+
+            var dfaStatesOnSymbolSet = new Set(onSymbol);
+            var dfaStatesOnSymbol = [].concat(_toConsumableArray(dfaStatesOnSymbolSet));
+
+            if (dfaStatesOnSymbol.length > 0) {
+              var dfaOnSymbolStr = dfaStatesOnSymbol.join(',');
+
+              dfaTable[dfaStateLabel][symbol] = dfaOnSymbolStr;
+
+              if (!dfaTable.hasOwnProperty(dfaOnSymbolStr)) {
+                worklist.unshift(dfaStatesOnSymbol);
+              }
+            }
+          }
+        } catch (err) {
+          _didIteratorError2 = true;
+          _iteratorError2 = err;
+        } finally {
+          try {
+            if (!_iteratorNormalCompletion2 && _iterator2.return) {
+              _iterator2.return();
+            }
+          } finally {
+            if (_didIteratorError2) {
+              throw _iteratorError2;
+            }
+          }
+        }
+      }
+
+      return this._transitionTable = this._remapStateNumbers(dfaTable);
+    }
+
+    /**
+     * Remaps state numbers in the resulting table:
+     * combined states '1,2,3' -> 1, '3,4' -> 2, etc.
+     */
+
+  }, {
+    key: '_remapStateNumbers',
+    value: function _remapStateNumbers(calculatedDFATable) {
+      var newStatesMap = {};
+
+      this._originalTransitionTable = calculatedDFATable;
+      var transitionTable = {};
+
+      Object.keys(calculatedDFATable).forEach(function (originalNumber, newNumber) {
+        newStatesMap[originalNumber] = newNumber + 1;
+      });
+
+      for (var originalNumber in calculatedDFATable) {
+        var originalRow = calculatedDFATable[originalNumber];
+        var row = {};
+
+        for (var symbol in originalRow) {
+          row[symbol] = newStatesMap[originalRow[symbol]];
+        }
+
+        transitionTable[newStatesMap[originalNumber]] = row;
+      }
+
+      // Remap accepting states.
+      this._originalAcceptingStateNumbers = this._acceptingStateNumbers;
+      this._acceptingStateNumbers = new Set();
+
+      var _iteratorNormalCompletion5 = true;
+      var _didIteratorError5 = false;
+      var _iteratorError5 = undefined;
+
+      try {
+        for (var _iterator5 = this._originalAcceptingStateNumbers[Symbol.iterator](), _step5; !(_iteratorNormalCompletion5 = (_step5 = _iterator5.next()).done); _iteratorNormalCompletion5 = true) {
+          var _originalNumber = _step5.value;
+
+          this._acceptingStateNumbers.add(newStatesMap[_originalNumber]);
+        }
+      } catch (err) {
+        _didIteratorError5 = true;
+        _iteratorError5 = err;
+      } finally {
+        try {
+          if (!_iteratorNormalCompletion5 && _iterator5.return) {
+            _iterator5.return();
+          }
+        } finally {
+          if (_didIteratorError5) {
+            throw _iteratorError5;
+          }
+        }
+      }
+
+      return transitionTable;
+    }
+
+    /**
+     * Returns original DFA table, where state numbers
+     * are combined numbers from NFA.
+     */
+
+  }, {
+    key: 'getOriginalTransitionTable',
+    value: function getOriginalTransitionTable() {
+      if (!this._originalTransitionTable) {
+        // Original table is determined during table construction.
+        this.getTransitionTable();
+      }
+      return this._originalTransitionTable;
+    }
+
+    /**
+     * Checks whether this DFA accepts a string.
+     */
+
+  }, {
+    key: 'matches',
+    value: function matches(string) {
+      var state = 1;
+      var i = 0;
+      var table = this.getTransitionTable();
+
+      while (string[i]) {
+        state = table[state][string[i++]];
+        if (!state) {
+          return false;
+        }
+      }
+
+      if (!this.getAcceptingStateNumbers().has(state)) {
+        return false;
+      }
+
+      return true;
+    }
+  }]);
+
+  return DFA;
+}();
+
+module.exports = DFA;

node_modules/regexp-tree/dist/interpreter/finite-automaton/index.js

@@ -0,0 +1,59 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+var NFA = require('./nfa/nfa');
+var DFA = require('./dfa/dfa');
+
+var nfaFromRegExp = require('./nfa/nfa-from-regexp');
+var builders = require('./nfa/builders');
+
+module.exports = {
+
+  /**
+   * Export NFA and DFA classes.
+   */
+  NFA: NFA,
+  DFA: DFA,
+
+  /**
+   * Expose builders.
+   */
+  builders: builders,
+
+  /**
+   * Builds an NFA for the passed regexp.
+   *
+   * @param string | AST | RegExp:
+   *
+   *   a regular expression in different representations: a string,
+   *   a RegExp object, or an AST.
+   */
+  toNFA: function toNFA(regexp) {
+    return nfaFromRegExp.build(regexp);
+  },
+
+
+  /**
+   * Builds DFA for the passed regexp.
+   *
+   * @param string | AST | RegExp:
+   *
+   *   a regular expression in different representations: a string,
+   *   a RegExp object, or an AST.
+   */
+  toDFA: function toDFA(regexp) {
+    return new DFA(this.toNFA(regexp));
+  },
+
+
+  /**
+   * Returns true if regexp accepts the string.
+   */
+  test: function test(regexp, string) {
+    return this.toDFA(regexp).matches(string);
+  }
+};

node_modules/regexp-tree/dist/interpreter/finite-automaton/nfa/builders.js

@@ -0,0 +1,227 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+var NFA = require('./nfa');
+var NFAState = require('./nfa-state');
+
+var _require = require('../special-symbols'),
+    EPSILON = _require.EPSILON;
+
+// -----------------------------------------------------------------------------
+// Char NFA fragment: `c`
+
+/**
+ * Char factory.
+ *
+ * Creates an NFA fragment for a single char.
+ *
+ * [in] --c--> [out]
+ */
+
+
+function char(c) {
+  var inState = new NFAState();
+  var outState = new NFAState({
+    accepting: true
+  });
+
+  return new NFA(inState.addTransition(c, outState), outState);
+}
+
+// -----------------------------------------------------------------------------
+// Epsilon NFA fragment
+
+/**
+ * Epsilon factory.
+ *
+ * Creates an NFA fragment for ε (recognizes an empty string).
+ *
+ * [in] --ε--> [out]
+ */
+function e() {
+  return char(EPSILON);
+}
+
+// -----------------------------------------------------------------------------
+// Alteration NFA fragment: `abc`
+
+/**
+ * Creates a connection between two NFA fragments on epsilon transition.
+ *
+ * [in-a] --a--> [out-a] --ε--> [in-b] --b--> [out-b]
+ */
+function altPair(first, second) {
+  first.out.accepting = false;
+  second.out.accepting = true;
+
+  first.out.addTransition(EPSILON, second.in);
+
+  return new NFA(first.in, second.out);
+}
+
+/**
+ * Alteration factory.
+ *
+ * Creates a alteration NFA for (at least) two NFA-fragments.
+ */
+function alt(first) {
+  for (var _len = arguments.length, fragments = Array(_len > 1 ? _len - 1 : 0), _key = 1; _key < _len; _key++) {
+    fragments[_key - 1] = arguments[_key];
+  }
+
+  var _iteratorNormalCompletion = true;
+  var _didIteratorError = false;
+  var _iteratorError = undefined;
+
+  try {
+    for (var _iterator = fragments[Symbol.iterator](), _step; !(_iteratorNormalCompletion = (_step = _iterator.next()).done); _iteratorNormalCompletion = true) {
+      var fragment = _step.value;
+
+      first = altPair(first, fragment);
+    }
+  } catch (err) {
+    _didIteratorError = true;
+    _iteratorError = err;
+  } finally {
+    try {
+      if (!_iteratorNormalCompletion && _iterator.return) {
+        _iterator.return();
+      }
+    } finally {
+      if (_didIteratorError) {
+        throw _iteratorError;
+      }
+    }
+  }
+
+  return first;
+}
+
+// -----------------------------------------------------------------------------
+// Disjunction NFA fragment: `a|b`
+
+/**
+ * Creates a disjunction choice between two fragments.
+ */
+function orPair(first, second) {
+  var inState = new NFAState();
+  var outState = new NFAState();
+
+  inState.addTransition(EPSILON, first.in);
+  inState.addTransition(EPSILON, second.in);
+
+  outState.accepting = true;
+  first.out.accepting = false;
+  second.out.accepting = false;
+
+  first.out.addTransition(EPSILON, outState);
+  second.out.addTransition(EPSILON, outState);
+
+  return new NFA(inState, outState);
+}
+
+/**
+ * Disjunction factory.
+ *
+ * Creates a disjunction NFA for (at least) two NFA-fragments.
+ */
+function or(first) {
+  for (var _len2 = arguments.length, fragments = Array(_len2 > 1 ? _len2 - 1 : 0), _key2 = 1; _key2 < _len2; _key2++) {
+    fragments[_key2 - 1] = arguments[_key2];
+  }
+
+  var _iteratorNormalCompletion2 = true;
+  var _didIteratorError2 = false;
+  var _iteratorError2 = undefined;
+
+  try {
+    for (var _iterator2 = fragments[Symbol.iterator](), _step2; !(_iteratorNormalCompletion2 = (_step2 = _iterator2.next()).done); _iteratorNormalCompletion2 = true) {
+      var fragment = _step2.value;
+
+      first = orPair(first, fragment);
+    }
+  } catch (err) {
+    _didIteratorError2 = true;
+    _iteratorError2 = err;
+  } finally {
+    try {
+      if (!_iteratorNormalCompletion2 && _iterator2.return) {
+        _iterator2.return();
+      }
+    } finally {
+      if (_didIteratorError2) {
+        throw _iteratorError2;
+      }
+    }
+  }
+
+  return first;
+}
+
+// -----------------------------------------------------------------------------
+// Kleene-closure
+
+/**
+ * Kleene star/closure.
+ *
+ * a*
+ */
+function repExplicit(fragment) {
+  var inState = new NFAState();
+  var outState = new NFAState({
+    accepting: true
+  });
+
+  // 0 or more.
+  inState.addTransition(EPSILON, fragment.in);
+  inState.addTransition(EPSILON, outState);
+
+  fragment.out.accepting = false;
+  fragment.out.addTransition(EPSILON, outState);
+  outState.addTransition(EPSILON, fragment.in);
+
+  return new NFA(inState, outState);
+}
+
+/**
+ * Optimized Kleene-star: just adds ε-transitions from
+ * input to the output, and back.
+ */
+function rep(fragment) {
+  fragment.in.addTransition(EPSILON, fragment.out);
+  fragment.out.addTransition(EPSILON, fragment.in);
+  return fragment;
+}
+
+/**
+ * Optimized Plus: just adds ε-transitions from
+ * the output to the input.
+ */
+function plusRep(fragment) {
+  fragment.out.addTransition(EPSILON, fragment.in);
+  return fragment;
+}
+
+/**
+ * Optimized ? repetition: just adds ε-transitions from
+ * the input to the output.
+ */
+function questionRep(fragment) {
+  fragment.in.addTransition(EPSILON, fragment.out);
+  return fragment;
+}
+
+module.exports = {
+  alt: alt,
+  char: char,
+  e: e,
+  or: or,
+  rep: rep,
+  repExplicit: repExplicit,
+  plusRep: plusRep,
+  questionRep: questionRep
+};

node_modules/regexp-tree/dist/interpreter/finite-automaton/nfa/nfa-from-regexp.js

@@ -0,0 +1,94 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+function _toConsumableArray(arr) { if (Array.isArray(arr)) { for (var i = 0, arr2 = Array(arr.length); i < arr.length; i++) { arr2[i] = arr[i]; } return arr2; } else { return Array.from(arr); } }
+
+var parser = require('../../../parser');
+
+var _require = require('./builders'),
+    alt = _require.alt,
+    char = _require.char,
+    or = _require.or,
+    rep = _require.rep,
+    plusRep = _require.plusRep,
+    questionRep = _require.questionRep;
+
+/**
+ * Helper `gen` function calls node type handler.
+ */
+
+
+function gen(node) {
+  if (node && !generator[node.type]) {
+    throw new Error(node.type + ' is not supported in NFA/DFA interpreter.');
+  }
+
+  return node ? generator[node.type](node) : '';
+}
+
+/**
+ * AST handler.
+ */
+var generator = {
+  RegExp: function RegExp(node) {
+    if (node.flags !== '') {
+      throw new Error('NFA/DFA: Flags are not supported yet.');
+    }
+
+    return gen(node.body);
+  },
+  Alternative: function Alternative(node) {
+    var fragments = (node.expressions || []).map(gen);
+    return alt.apply(undefined, _toConsumableArray(fragments));
+  },
+  Disjunction: function Disjunction(node) {
+    return or(gen(node.left), gen(node.right));
+  },
+  Repetition: function Repetition(node) {
+    switch (node.quantifier.kind) {
+      case '*':
+        return rep(gen(node.expression));
+      case '+':
+        return plusRep(gen(node.expression));
+      case '?':
+        return questionRep(gen(node.expression));
+      default:
+        throw new Error('Unknown repeatition: ' + node.quantifier.kind + '.');
+    }
+  },
+  Char: function Char(node) {
+    if (node.kind !== 'simple') {
+      throw new Error('NFA/DFA: Only simple chars are supported yet.');
+    }
+
+    return char(node.value);
+  },
+  Group: function Group(node) {
+    return gen(node.expression);
+  }
+};
+
+module.exports = {
+  /**
+   * Builds an NFA from the passed regexp.
+   */
+  build: function build(regexp) {
+    var ast = regexp;
+
+    if (regexp instanceof RegExp) {
+      regexp = '' + regexp;
+    }
+
+    if (typeof regexp === 'string') {
+      ast = parser.parse(regexp, {
+        captureLocations: true
+      });
+    }
+
+    return gen(ast);
+  }
+};

node_modules/regexp-tree/dist/interpreter/finite-automaton/nfa/nfa-state.js

@@ -0,0 +1,220 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();
+
+function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
+
+function _possibleConstructorReturn(self, call) { if (!self) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return call && (typeof call === "object" || typeof call === "function") ? call : self; }
+
+function _inherits(subClass, superClass) { if (typeof superClass !== "function" && superClass !== null) { throw new TypeError("Super expression must either be null or a function, not " + typeof superClass); } subClass.prototype = Object.create(superClass && superClass.prototype, { constructor: { value: subClass, enumerable: false, writable: true, configurable: true } }); if (superClass) Object.setPrototypeOf ? Object.setPrototypeOf(subClass, superClass) : subClass.__proto__ = superClass; }
+
+var State = require('../state');
+
+var _require = require('../special-symbols'),
+    EPSILON = _require.EPSILON;
+
+/**
+ * NFA state.
+ *
+ * Allows nondeterministic transitions to several states on the
+ * same symbol, and also epsilon-transitions.
+ */
+
+
+var NFAState = function (_State) {
+  _inherits(NFAState, _State);
+
+  function NFAState() {
+    _classCallCheck(this, NFAState);
+
+    return _possibleConstructorReturn(this, (NFAState.__proto__ || Object.getPrototypeOf(NFAState)).apply(this, arguments));
+  }
+
+  _createClass(NFAState, [{
+    key: 'matches',
+
+
+    /**
+     * Whether this state matches a string.
+     *
+     * We maintain set of visited epsilon-states to avoid infinite loops
+     * when an epsilon-transition goes eventually to itself.
+     *
+     * NOTE: this function is rather "educational", since we use DFA for strings
+     * matching. DFA is built on top of NFA, and uses fast transition table.
+     */
+    value: function matches(string) {
+      var visited = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : new Set();
+
+      // An epsilon-state has been visited, stop to avoid infinite loop.
+      if (visited.has(this)) {
+        return false;
+      }
+
+      visited.add(this);
+
+      // No symbols left..
+      if (string.length === 0) {
+        // .. and we're in the accepting state.
+        if (this.accepting) {
+          return true;
+        }
+
+        // Check if we can reach any accepting state from
+        // on the epsilon transitions.
+        var _iteratorNormalCompletion = true;
+        var _didIteratorError = false;
+        var _iteratorError = undefined;
+
+        try {
+          for (var _iterator = this.getTransitionsOnSymbol(EPSILON)[Symbol.iterator](), _step; !(_iteratorNormalCompletion = (_step = _iterator.next()).done); _iteratorNormalCompletion = true) {
+            var nextState = _step.value;
+
+            if (nextState.matches('', visited)) {
+              return true;
+            }
+          }
+        } catch (err) {
+          _didIteratorError = true;
+          _iteratorError = err;
+        } finally {
+          try {
+            if (!_iteratorNormalCompletion && _iterator.return) {
+              _iterator.return();
+            }
+          } finally {
+            if (_didIteratorError) {
+              throw _iteratorError;
+            }
+          }
+        }
+
+        return false;
+      }
+
+      // Else, we get some symbols.
+      var symbol = string[0];
+      var rest = string.slice(1);
+
+      var symbolTransitions = this.getTransitionsOnSymbol(symbol);
+      var _iteratorNormalCompletion2 = true;
+      var _didIteratorError2 = false;
+      var _iteratorError2 = undefined;
+
+      try {
+        for (var _iterator2 = symbolTransitions[Symbol.iterator](), _step2; !(_iteratorNormalCompletion2 = (_step2 = _iterator2.next()).done); _iteratorNormalCompletion2 = true) {
+          var _nextState = _step2.value;
+
+          if (_nextState.matches(rest)) {
+            return true;
+          }
+        }
+
+        // If we couldn't match on symbol, check still epsilon-transitions
+        // without consuming the symbol (i.e. continue from `string`, not `rest`).
+      } catch (err) {
+        _didIteratorError2 = true;
+        _iteratorError2 = err;
+      } finally {
+        try {
+          if (!_iteratorNormalCompletion2 && _iterator2.return) {
+            _iterator2.return();
+          }
+        } finally {
+          if (_didIteratorError2) {
+            throw _iteratorError2;
+          }
+        }
+      }
+
+      var _iteratorNormalCompletion3 = true;
+      var _didIteratorError3 = false;
+      var _iteratorError3 = undefined;
+
+      try {
+        for (var _iterator3 = this.getTransitionsOnSymbol(EPSILON)[Symbol.iterator](), _step3; !(_iteratorNormalCompletion3 = (_step3 = _iterator3.next()).done); _iteratorNormalCompletion3 = true) {
+          var _nextState2 = _step3.value;
+
+          if (_nextState2.matches(string, visited)) {
+            return true;
+          }
+        }
+      } catch (err) {
+        _didIteratorError3 = true;
+        _iteratorError3 = err;
+      } finally {
+        try {
+          if (!_iteratorNormalCompletion3 && _iterator3.return) {
+            _iterator3.return();
+          }
+        } finally {
+          if (_didIteratorError3) {
+            throw _iteratorError3;
+          }
+        }
+      }
+
+      return false;
+    }
+
+    /**
+     * Returns an ε-closure for this state:
+     * self + all states following ε-transitions.
+     */
+
+  }, {
+    key: 'getEpsilonClosure',
+    value: function getEpsilonClosure() {
+      var _this2 = this;
+
+      if (!this._epsilonClosure) {
+        (function () {
+          var epsilonTransitions = _this2.getTransitionsOnSymbol(EPSILON);
+          var closure = _this2._epsilonClosure = new Set();
+          closure.add(_this2);
+          var _iteratorNormalCompletion4 = true;
+          var _didIteratorError4 = false;
+          var _iteratorError4 = undefined;
+
+          try {
+            for (var _iterator4 = epsilonTransitions[Symbol.iterator](), _step4; !(_iteratorNormalCompletion4 = (_step4 = _iterator4.next()).done); _iteratorNormalCompletion4 = true) {
+              var nextState = _step4.value;
+
+              if (!closure.has(nextState)) {
+                closure.add(nextState);
+                var nextClosure = nextState.getEpsilonClosure();
+                nextClosure.forEach(function (state) {
+                  return closure.add(state);
+                });
+              }
+            }
+          } catch (err) {
+            _didIteratorError4 = true;
+            _iteratorError4 = err;
+          } finally {
+            try {
+              if (!_iteratorNormalCompletion4 && _iterator4.return) {
+                _iterator4.return();
+              }
+            } finally {
+              if (_didIteratorError4) {
+                throw _iteratorError4;
+              }
+            }
+          }
+        })();
+      }
+
+      return this._epsilonClosure;
+    }
+  }]);
+
+  return NFAState;
+}(State);
+
+module.exports = NFAState;

node_modules/regexp-tree/dist/interpreter/finite-automaton/nfa/nfa.js

@@ -0,0 +1,234 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+var _slicedToArray = function () { function sliceIterator(arr, i) { var _arr = []; var _n = true; var _d = false; var _e = undefined; try { for (var _i = arr[Symbol.iterator](), _s; !(_n = (_s = _i.next()).done); _n = true) { _arr.push(_s.value); if (i && _arr.length === i) break; } } catch (err) { _d = true; _e = err; } finally { try { if (!_n && _i["return"]) _i["return"](); } finally { if (_d) throw _e; } } return _arr; } return function (arr, i) { if (Array.isArray(arr)) { return arr; } else if (Symbol.iterator in Object(arr)) { return sliceIterator(arr, i); } else { throw new TypeError("Invalid attempt to destructure non-iterable instance"); } }; }();
+
+var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();
+
+function _toConsumableArray(arr) { if (Array.isArray(arr)) { for (var i = 0, arr2 = Array(arr.length); i < arr.length; i++) { arr2[i] = arr[i]; } return arr2; } else { return Array.from(arr); } }
+
+function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
+
+var _require = require('../special-symbols'),
+    EPSILON = _require.EPSILON,
+    EPSILON_CLOSURE = _require.EPSILON_CLOSURE;
+
+/**
+ * NFA fragment.
+ *
+ * NFA sub-fragments can be combined to a larger NFAs building
+ * the resulting machine. Combining the fragments is done by patching
+ * edges of the in- and out-states.
+ *
+ * 2-states implementation, `in`, and `out`. Eventually all transitions
+ * go to the same `out`, which can further be connected via ε-transition
+ * with other fragment.
+ */
+
+
+var NFA = function () {
+  function NFA(inState, outState) {
+    _classCallCheck(this, NFA);
+
+    this.in = inState;
+    this.out = outState;
+  }
+
+  /**
+   * Tries to recognize a string based on this NFA fragment.
+   */
+
+
+  _createClass(NFA, [{
+    key: 'matches',
+    value: function matches(string) {
+      return this.in.matches(string);
+    }
+
+    /**
+     * Returns an alphabet for this NFA.
+     */
+
+  }, {
+    key: 'getAlphabet',
+    value: function getAlphabet() {
+      if (!this._alphabet) {
+        this._alphabet = new Set();
+        var table = this.getTransitionTable();
+        for (var state in table) {
+          var transitions = table[state];
+          for (var symbol in transitions) {
+            if (symbol !== EPSILON_CLOSURE) {
+              this._alphabet.add(symbol);
+            }
+          }
+        }
+      }
+      return this._alphabet;
+    }
+
+    /**
+     * Returns set of accepting states.
+     */
+
+  }, {
+    key: 'getAcceptingStates',
+    value: function getAcceptingStates() {
+      if (!this._acceptingStates) {
+        // States are determined during table construction.
+        this.getTransitionTable();
+      }
+      return this._acceptingStates;
+    }
+
+    /**
+     * Returns accepting state numbers.
+     */
+
+  }, {
+    key: 'getAcceptingStateNumbers',
+    value: function getAcceptingStateNumbers() {
+      if (!this._acceptingStateNumbers) {
+        this._acceptingStateNumbers = new Set();
+        var _iteratorNormalCompletion = true;
+        var _didIteratorError = false;
+        var _iteratorError = undefined;
+
+        try {
+          for (var _iterator = this.getAcceptingStates()[Symbol.iterator](), _step; !(_iteratorNormalCompletion = (_step = _iterator.next()).done); _iteratorNormalCompletion = true) {
+            var acceptingState = _step.value;
+
+            this._acceptingStateNumbers.add(acceptingState.number);
+          }
+        } catch (err) {
+          _didIteratorError = true;
+          _iteratorError = err;
+        } finally {
+          try {
+            if (!_iteratorNormalCompletion && _iterator.return) {
+              _iterator.return();
+            }
+          } finally {
+            if (_didIteratorError) {
+              throw _iteratorError;
+            }
+          }
+        }
+      }
+      return this._acceptingStateNumbers;
+    }
+
+    /**
+     * Builds and returns transition table.
+     */
+
+  }, {
+    key: 'getTransitionTable',
+    value: function getTransitionTable() {
+      var _this = this;
+
+      if (!this._transitionTable) {
+        this._transitionTable = {};
+        this._acceptingStates = new Set();
+
+        var visited = new Set();
+        var symbols = new Set();
+
+        var visitState = function visitState(state) {
+          if (visited.has(state)) {
+            return;
+          }
+
+          visited.add(state);
+          state.number = visited.size;
+          _this._transitionTable[state.number] = {};
+
+          if (state.accepting) {
+            _this._acceptingStates.add(state);
+          }
+
+          var transitions = state.getTransitions();
+
+          var _iteratorNormalCompletion2 = true;
+          var _didIteratorError2 = false;
+          var _iteratorError2 = undefined;
+
+          try {
+            for (var _iterator2 = transitions[Symbol.iterator](), _step2; !(_iteratorNormalCompletion2 = (_step2 = _iterator2.next()).done); _iteratorNormalCompletion2 = true) {
+              var _ref = _step2.value;
+
+              var _ref2 = _slicedToArray(_ref, 2);
+
+              var symbol = _ref2[0];
+              var symbolTransitions = _ref2[1];
+
+              var combinedState = [];
+              symbols.add(symbol);
+              var _iteratorNormalCompletion3 = true;
+              var _didIteratorError3 = false;
+              var _iteratorError3 = undefined;
+
+              try {
+                for (var _iterator3 = symbolTransitions[Symbol.iterator](), _step3; !(_iteratorNormalCompletion3 = (_step3 = _iterator3.next()).done); _iteratorNormalCompletion3 = true) {
+                  var nextState = _step3.value;
+
+                  visitState(nextState);
+                  combinedState.push(nextState.number);
+                }
+              } catch (err) {
+                _didIteratorError3 = true;
+                _iteratorError3 = err;
+              } finally {
+                try {
+                  if (!_iteratorNormalCompletion3 && _iterator3.return) {
+                    _iterator3.return();
+                  }
+                } finally {
+                  if (_didIteratorError3) {
+                    throw _iteratorError3;
+                  }
+                }
+              }
+
+              _this._transitionTable[state.number][symbol] = combinedState;
+            }
+          } catch (err) {
+            _didIteratorError2 = true;
+            _iteratorError2 = err;
+          } finally {
+            try {
+              if (!_iteratorNormalCompletion2 && _iterator2.return) {
+                _iterator2.return();
+              }
+            } finally {
+              if (_didIteratorError2) {
+                throw _iteratorError2;
+              }
+            }
+          }
+        };
+
+        // Traverse the graph starting from the `in`.
+        visitState(this.in);
+
+        // Append epsilon-closure column.
+        visited.forEach(function (state) {
+          delete _this._transitionTable[state.number][EPSILON];
+          _this._transitionTable[state.number][EPSILON_CLOSURE] = [].concat(_toConsumableArray(state.getEpsilonClosure())).map(function (s) {
+            return s.number;
+          });
+        });
+      }
+
+      return this._transitionTable;
+    }
+  }]);
+
+  return NFA;
+}();
+
+module.exports = NFA;

node_modules/regexp-tree/dist/interpreter/finite-automaton/special-symbols.js

@@ -0,0 +1,22 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+/**
+ * Epsilon, the empty string.
+ */
+
+var EPSILON = 'ε';
+
+/**
+ * Epsilon-closure.
+ */
+var EPSILON_CLOSURE = EPSILON + '*';
+
+module.exports = {
+  EPSILON: EPSILON,
+  EPSILON_CLOSURE: EPSILON_CLOSURE
+};

node_modules/regexp-tree/dist/interpreter/finite-automaton/state.js

@@ -0,0 +1,81 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+/**
+ * A generic FA State class (base for NFA and DFA).
+ *
+ * Maintains the transition map, and the flag whether
+ * the state is accepting.
+ */
+
+var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();
+
+function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
+
+var State = function () {
+  function State() {
+    var _ref = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : {},
+        _ref$accepting = _ref.accepting,
+        accepting = _ref$accepting === undefined ? false : _ref$accepting;
+
+    _classCallCheck(this, State);
+
+    /**
+     * Outgoing transitions to other states.
+     */
+    this._transitions = new Map();
+
+    /**
+     * Whether the state is accepting.
+     */
+    this.accepting = accepting;
+  }
+
+  /**
+   * Returns transitions for this state.
+   */
+
+
+  _createClass(State, [{
+    key: 'getTransitions',
+    value: function getTransitions() {
+      return this._transitions;
+    }
+
+    /**
+     * Creates a transition on symbol.
+     */
+
+  }, {
+    key: 'addTransition',
+    value: function addTransition(symbol, toState) {
+      this.getTransitionsOnSymbol(symbol).add(toState);
+      return this;
+    }
+
+    /**
+     * Returns transitions set on symbol.
+     */
+
+  }, {
+    key: 'getTransitionsOnSymbol',
+    value: function getTransitionsOnSymbol(symbol) {
+      var transitions = this._transitions.get(symbol);
+
+      if (!transitions) {
+        transitions = new Set();
+        this._transitions.set(symbol, transitions);
+      }
+
+      return transitions;
+    }
+  }]);
+
+  return State;
+}();
+
+module.exports = State;

node_modules/regexp-tree/dist/interpreter/finite-automaton/table-printer.js

@@ -0,0 +1,27 @@
+'use strict';
+
+function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
+
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2015-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+var Table = require('cli-table3');
+
+/**
+ * Wrapper class over `cli-table3` with default options preset.
+ */
+
+var TablePrinter = function TablePrinter(options) {
+  _classCallCheck(this, TablePrinter);
+
+  return new Table(Object.assign({}, options, {
+    style: {
+      head: ['blue'],
+      border: ['gray']
+    }
+  }));
+};
+
+module.exports = TablePrinter;

node_modules/regexp-tree/dist/interpreter/finite-automaton/transforms/char-plus-to-star-transform.js

@@ -0,0 +1,35 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+/**
+ * A regexp-tree plugin to replace `a+` to `aa*`, since NFA/DFA
+ * handles Kleene-closure `a*`, and `a+` is just a syntactic sugar.
+ */
+
+module.exports = {
+  Repetition: function Repetition(path) {
+    var node = path.node,
+        parent = path.parent;
+
+
+    if (node.quantifier.kind !== '+') {
+      return;
+    }
+
+    if (parent.type === 'Alternative') {
+      path.getParent().insertChildAt(node.expression, path.index);
+    } else {
+      path.replace({
+        type: 'Alternative',
+        expressions: [node.expression, node]
+      });
+    }
+
+    // Change quantifier.
+    node.quantifier.kind = '*';
+  }
+};

node_modules/regexp-tree/dist/interpreter/finite-automaton/transforms/index.js

@@ -0,0 +1,10 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+module.exports = [
+// a+ -> aa*
+require('./char-plus-to-star-transform')];

node_modules/regexp-tree/dist/optimizer/index.js

@@ -0,0 +1,83 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+var clone = require('../utils/clone');
+var parser = require('../parser');
+var transform = require('../transform');
+var optimizationTransforms = require('./transforms');
+
+module.exports = {
+  /**
+   * Optimizer transforms a regular expression into an optimized version,
+   * replacing some sub-expressions with their idiomatic patterns.
+   *
+   * @param string | RegExp | AST - a regexp to optimize.
+   *
+   * @return TransformResult - an optimized regexp.
+   *
+   * Example:
+   *
+   *   /[a-zA-Z_0-9][a-zA-Z_0-9]*\e{1,}/
+   *
+   * Optimized to:
+   *
+   *   /\w+e+/
+   */
+  optimize: function optimize(regexp) {
+    var transformsWhitelist = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : [];
+
+    var transformToApply = transformsWhitelist.length > 0 ? transformsWhitelist : Object.keys(optimizationTransforms);
+
+    var ast = regexp;
+    if (regexp instanceof RegExp) {
+      regexp = '' + regexp;
+    }
+
+    if (typeof regexp === 'string') {
+      ast = parser.parse(regexp);
+    }
+
+    var result = new transform.TransformResult(ast);
+    var prevResultString = void 0;
+
+    do {
+      // Get a copy of the current state here so
+      // we can compare it with the state at the
+      // end of the loop.
+      prevResultString = result.toString();
+      ast = clone(result.getAST());
+
+      transformToApply.forEach(function (transformName) {
+        if (!optimizationTransforms.hasOwnProperty(transformName)) {
+          throw new Error('Unknown optimization-transform: ' + transformName + '. ' + 'Available transforms are: ' + Object.keys(optimizationTransforms).join(', '));
+        }
+
+        var transformer = optimizationTransforms[transformName];
+
+        // Don't override result just yet since we
+        // might want to rollback the transform
+        var newResult = transform.transform(ast, transformer);
+
+        if (newResult.toString() !== result.toString()) {
+          if (newResult.toString().length <= result.toString().length) {
+            result = newResult;
+          } else {
+            // Result has changed but is not shorter:
+            // restore ast to its previous state.
+
+            ast = clone(result.getAST());
+          }
+        }
+      });
+
+      // Keep running the optimizer until it stops
+      // making any change to the regexp.
+    } while (result.toString() !== prevResultString);
+
+    return result;
+  }
+};

node_modules/regexp-tree/dist/optimizer/transforms/char-case-insensitive-lowercase-transform.js

@@ -0,0 +1,110 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+var UPPER_A_CP = 'A'.codePointAt(0);
+var UPPER_Z_CP = 'Z'.codePointAt(0);
+/**
+ * Transforms case-insensitive regexp to lowercase
+ *
+ * /AaBbÏ/i -> /aabbï/i
+ */
+module.exports = {
+  _AZClassRanges: null,
+  _hasUFlag: false,
+  init: function init(ast) {
+    this._AZClassRanges = new Set();
+    this._hasUFlag = ast.flags.includes('u');
+  },
+  shouldRun: function shouldRun(ast) {
+    return ast.flags.includes('i');
+  },
+  Char: function Char(path) {
+    var node = path.node,
+        parent = path.parent;
+
+    if (isNaN(node.codePoint)) {
+      return;
+    }
+
+    // Engine support for case-insensitive matching without the u flag
+    // for characters above \u1000 does not seem reliable.
+    if (!this._hasUFlag && node.codePoint >= 0x1000) {
+      return;
+    }
+
+    if (parent.type === 'ClassRange') {
+      // The only class ranges we handle must be inside A-Z.
+      // After the `from` char is processed, the isAZClassRange test
+      // will be false, so we use a Set to keep track of parents and
+      // process the `to` char.
+      if (!this._AZClassRanges.has(parent) && !isAZClassRange(parent)) {
+        return;
+      }
+      this._AZClassRanges.add(parent);
+    }
+
+    var lower = node.symbol.toLowerCase();
+    if (lower !== node.symbol) {
+      node.value = displaySymbolAsValue(lower, node);
+      node.symbol = lower;
+      node.codePoint = lower.codePointAt(0);
+    }
+  }
+};
+
+function isAZClassRange(classRange) {
+  var from = classRange.from,
+      to = classRange.to;
+  // A-Z
+
+  return from.codePoint >= UPPER_A_CP && from.codePoint <= UPPER_Z_CP && to.codePoint >= UPPER_A_CP && to.codePoint <= UPPER_Z_CP;
+}
+
+function displaySymbolAsValue(symbol, node) {
+  var codePoint = symbol.codePointAt(0);
+  if (node.kind === 'decimal') {
+    return '\\' + codePoint;
+  }
+  if (node.kind === 'oct') {
+    return '\\0' + codePoint.toString(8);
+  }
+  if (node.kind === 'hex') {
+    return '\\x' + codePoint.toString(16);
+  }
+  if (node.kind === 'unicode') {
+    if (node.isSurrogatePair) {
+      var _getSurrogatePairFrom = getSurrogatePairFromCodePoint(codePoint),
+          lead = _getSurrogatePairFrom.lead,
+          trail = _getSurrogatePairFrom.trail;
+
+      return '\\u' + '0'.repeat(4 - lead.length) + lead + '\\u' + '0'.repeat(4 - trail.length) + trail;
+    } else if (node.value.includes('{')) {
+      return '\\u{' + codePoint.toString(16) + '}';
+    } else {
+      var code = codePoint.toString(16);
+      return '\\u' + '0'.repeat(4 - code.length) + code;
+    }
+  }
+  // simple
+  return symbol;
+}
+
+/**
+ * Converts a code point to a surrogate pair.
+ * Conversion algorithm is taken from The Unicode Standard 3.0 Section 3.7
+ * (https://www.unicode.org/versions/Unicode3.0.0/ch03.pdf)
+ * @param {number} codePoint - Between 0x10000 and 0x10ffff
+ * @returns {{lead: string, trail: string}}
+ */
+function getSurrogatePairFromCodePoint(codePoint) {
+  var lead = Math.floor((codePoint - 0x10000) / 0x400) + 0xd800;
+  var trail = (codePoint - 0x10000) % 0x400 + 0xdc00;
+  return {
+    lead: lead.toString(16),
+    trail: trail.toString(16)
+  };
+}

node_modules/regexp-tree/dist/optimizer/transforms/char-class-classranges-merge-transform.js

@@ -0,0 +1,339 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+/**
+ * A regexp-tree plugin to merge class ranges.
+ *
+ * [a-ec] -> [a-e]
+ * [a-ec-e] -> [a-e]
+ * [\w\da-f] -> [\w]
+ * [abcdef] -> [a-f]
+ */
+
+module.exports = {
+  _hasIUFlags: false,
+  init: function init(ast) {
+    this._hasIUFlags = ast.flags.includes('i') && ast.flags.includes('u');
+  },
+  CharacterClass: function CharacterClass(path) {
+    var node = path.node;
+
+    var expressions = node.expressions;
+
+    var metas = [];
+    // Extract metas
+    expressions.forEach(function (expression) {
+      if (isMeta(expression)) {
+        metas.push(expression.value);
+      }
+    });
+
+    expressions.sort(sortCharClass);
+
+    for (var i = 0; i < expressions.length; i++) {
+      var expression = expressions[i];
+      if (fitsInMetas(expression, metas, this._hasIUFlags) || combinesWithPrecedingClassRange(expression, expressions[i - 1]) || combinesWithFollowingClassRange(expression, expressions[i + 1])) {
+        expressions.splice(i, 1);
+        i--;
+      } else {
+        var nbMergedChars = charCombinesWithPrecedingChars(expression, i, expressions);
+        expressions.splice(i - nbMergedChars + 1, nbMergedChars);
+        i -= nbMergedChars;
+      }
+    }
+  }
+};
+
+/**
+ * Sorts expressions in char class in the following order:
+ * - meta chars, ordered alphabetically by value
+ * - chars (except `control` kind) and class ranges, ordered alphabetically (`from` char is used for class ranges)
+ * - if ambiguous, class range comes before char
+ * - if ambiguous between two class ranges, orders alphabetically by `to` char
+ * - control chars, ordered alphabetically by value
+ * @param {Object} a - Left Char or ClassRange node
+ * @param {Object} b - Right Char or ClassRange node
+ * @returns {number}
+ */
+function sortCharClass(a, b) {
+  var aValue = getSortValue(a);
+  var bValue = getSortValue(b);
+
+  if (aValue === bValue) {
+    // We want ClassRange before Char
+    // [bb-d] -> [b-db]
+    if (a.type === 'ClassRange' && b.type !== 'ClassRange') {
+      return -1;
+    }
+    if (b.type === 'ClassRange' && a.type !== 'ClassRange') {
+      return 1;
+    }
+    if (a.type === 'ClassRange' && b.type === 'ClassRange') {
+      return getSortValue(a.to) - getSortValue(b.to);
+    }
+    if (isMeta(a) && isMeta(b) || isControl(a) && isControl(b)) {
+      return a.value < b.value ? -1 : 1;
+    }
+  }
+  return aValue - bValue;
+}
+
+/**
+ * @param {Object} expression - Char or ClassRange node
+ * @returns {number}
+ */
+function getSortValue(expression) {
+  if (expression.type === 'Char') {
+    if (expression.kind === 'control') {
+      return Infinity;
+    }
+    if (expression.kind === 'meta' && isNaN(expression.codePoint)) {
+      return -1;
+    }
+    return expression.codePoint;
+  }
+  // ClassRange
+  return expression.from.codePoint;
+}
+
+/**
+ * Checks if a node is a meta char from the set \d\w\s\D\W\S
+ * @param {Object} expression - Char or ClassRange node
+ * @param {?string} value
+ * @returns {boolean}
+ */
+function isMeta(expression) {
+  var value = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : null;
+
+  return expression.type === 'Char' && expression.kind === 'meta' && (value ? expression.value === value : /^\\[dws]$/i.test(expression.value));
+}
+
+/**
+ * @param {Object} expression - Char or ClassRange node
+ * @returns {boolean}
+ */
+function isControl(expression) {
+  return expression.type === 'Char' && expression.kind === 'control';
+}
+
+/**
+ * @param {Object} expression - Char or ClassRange node
+ * @param {string[]} metas - Array of meta chars, e.g. ["\\w", "\\s"]
+ * @param {boolean} hasIUFlags
+ * @returns {boolean}
+ */
+function fitsInMetas(expression, metas, hasIUFlags) {
+  for (var i = 0; i < metas.length; i++) {
+    if (fitsInMeta(expression, metas[i], hasIUFlags)) {
+      return true;
+    }
+  }
+  return false;
+}
+
+/**
+ * @param {Object} expression - Char or ClassRange node
+ * @param {string} meta - e.g. "\\w"
+ * @param {boolean} hasIUFlags
+ * @returns {boolean}
+ */
+function fitsInMeta(expression, meta, hasIUFlags) {
+  if (expression.type === 'ClassRange') {
+    return fitsInMeta(expression.from, meta, hasIUFlags) && fitsInMeta(expression.to, meta, hasIUFlags);
+  }
+
+  // Special cases:
+  // \S contains \w and \d
+  if (meta === '\\S' && (isMeta(expression, '\\w') || isMeta(expression, '\\d'))) {
+    return true;
+  }
+  // \D contains \W and \s
+  if (meta === '\\D' && (isMeta(expression, '\\W') || isMeta(expression, '\\s'))) {
+    return true;
+  }
+  // \w contains \d
+  if (meta === '\\w' && isMeta(expression, '\\d')) {
+    return true;
+  }
+  // \W contains \s
+  if (meta === '\\W' && isMeta(expression, '\\s')) {
+    return true;
+  }
+
+  if (expression.type !== 'Char' || isNaN(expression.codePoint)) {
+    return false;
+  }
+
+  if (meta === '\\s') {
+    return fitsInMetaS(expression);
+  }
+  if (meta === '\\S') {
+    return !fitsInMetaS(expression);
+  }
+  if (meta === '\\d') {
+    return fitsInMetaD(expression);
+  }
+  if (meta === '\\D') {
+    return !fitsInMetaD(expression);
+  }
+  if (meta === '\\w') {
+    return fitsInMetaW(expression, hasIUFlags);
+  }
+  if (meta === '\\W') {
+    return !fitsInMetaW(expression, hasIUFlags);
+  }
+  return false;
+}
+
+/**
+ * @param {Object} expression - Char node with codePoint
+ * @returns {boolean}
+ */
+function fitsInMetaS(expression) {
+  return expression.codePoint === 0x0009 || // \t
+  expression.codePoint === 0x000a || // \n
+  expression.codePoint === 0x000b || // \v
+  expression.codePoint === 0x000c || // \f
+  expression.codePoint === 0x000d || // \r
+  expression.codePoint === 0x0020 || // space
+  expression.codePoint === 0x00a0 || // nbsp
+  expression.codePoint === 0x1680 || // part of Zs
+  expression.codePoint >= 0x2000 && expression.codePoint <= 0x200a || // part of Zs
+  expression.codePoint === 0x2028 || // line separator
+  expression.codePoint === 0x2029 || // paragraph separator
+  expression.codePoint === 0x202f || // part of Zs
+  expression.codePoint === 0x205f || // part of Zs
+  expression.codePoint === 0x3000 || // part of Zs
+  expression.codePoint === 0xfeff; // zwnbsp
+}
+
+/**
+ * @param {Object} expression - Char node with codePoint
+ * @returns {boolean}
+ */
+function fitsInMetaD(expression) {
+  return expression.codePoint >= 0x30 && expression.codePoint <= 0x39; // 0-9
+}
+
+/**
+ * @param {Object} expression - Char node with codePoint
+ * @param {boolean} hasIUFlags
+ * @returns {boolean}
+ */
+function fitsInMetaW(expression, hasIUFlags) {
+  return fitsInMetaD(expression) || expression.codePoint >= 0x41 && expression.codePoint <= 0x5a || // A-Z
+  expression.codePoint >= 0x61 && expression.codePoint <= 0x7a || // a-z
+  expression.value === '_' || hasIUFlags && (expression.codePoint === 0x017f || expression.codePoint === 0x212a);
+}
+
+/**
+ * @param {Object} expression - Char or ClassRange node
+ * @param {Object} classRange - Char or ClassRange node
+ * @returns {boolean}
+ */
+function combinesWithPrecedingClassRange(expression, classRange) {
+  if (classRange && classRange.type === 'ClassRange') {
+
+    if (fitsInClassRange(expression, classRange)) {
+      // [a-gc] -> [a-g]
+      // [a-gc-e] -> [a-g]
+      return true;
+    } else if (
+    // We only want \w chars or char codes to keep readability
+    isMetaWCharOrCode(expression) && classRange.to.codePoint === expression.codePoint - 1) {
+      // [a-de] -> [a-e]
+      classRange.to = expression;
+      return true;
+    } else if (expression.type === 'ClassRange' && expression.from.codePoint <= classRange.to.codePoint + 1 && expression.to.codePoint >= classRange.from.codePoint - 1) {
+      // [a-db-f] -> [a-f]
+      // [b-fa-d] -> [a-f]
+      // [a-cd-f] -> [a-f]
+      if (expression.from.codePoint < classRange.from.codePoint) {
+        classRange.from = expression.from;
+      }
+      if (expression.to.codePoint > classRange.to.codePoint) {
+        classRange.to = expression.to;
+      }
+      return true;
+    }
+  }
+  return false;
+}
+
+/**
+ * @param {Object} expression - Char or ClassRange node
+ * @param {Object} classRange - Char or ClassRange node
+ * @returns {boolean}
+ */
+function combinesWithFollowingClassRange(expression, classRange) {
+  if (classRange && classRange.type === 'ClassRange') {
+    // Considering the elements were ordered alphabetically,
+    // there is only one case to handle
+    // [ab-e] -> [a-e]
+    if (
+    // We only want \w chars or char codes to keep readability
+    isMetaWCharOrCode(expression) && classRange.from.codePoint === expression.codePoint + 1) {
+      classRange.from = expression;
+      return true;
+    }
+  }
+
+  return false;
+}
+
+/**
+ * @param {Object} expression - Char or ClassRange node
+ * @param {Object} classRange - ClassRange node
+ * @returns {boolean}
+ */
+function fitsInClassRange(expression, classRange) {
+  if (expression.type === 'Char' && isNaN(expression.codePoint)) {
+    return false;
+  }
+  if (expression.type === 'ClassRange') {
+    return fitsInClassRange(expression.from, classRange) && fitsInClassRange(expression.to, classRange);
+  }
+  return expression.codePoint >= classRange.from.codePoint && expression.codePoint <= classRange.to.codePoint;
+}
+
+/**
+ * @param {Object} expression - Char or ClassRange node
+ * @param {Number} index
+ * @param {Object[]} expressions - expressions in CharClass
+ * @returns {number} - Number of characters combined with expression
+ */
+function charCombinesWithPrecedingChars(expression, index, expressions) {
+  // We only want \w chars or char codes to keep readability
+  if (!isMetaWCharOrCode(expression)) {
+    return 0;
+  }
+  var nbMergedChars = 0;
+  while (index > 0) {
+    var currentExpression = expressions[index];
+    var precedingExpresion = expressions[index - 1];
+    if (isMetaWCharOrCode(precedingExpresion) && precedingExpresion.codePoint === currentExpression.codePoint - 1) {
+      nbMergedChars++;
+      index--;
+    } else {
+      break;
+    }
+  }
+
+  if (nbMergedChars > 1) {
+    expressions[index] = {
+      type: 'ClassRange',
+      from: expressions[index],
+      to: expression
+    };
+    return nbMergedChars;
+  }
+  return 0;
+}
+
+function isMetaWCharOrCode(expression) {
+  return expression && expression.type === 'Char' && !isNaN(expression.codePoint) && (fitsInMetaW(expression, false) || expression.kind === 'unicode' || expression.kind === 'hex' || expression.kind === 'oct' || expression.kind === 'decimal');
+}

node_modules/regexp-tree/dist/optimizer/transforms/char-class-classranges-to-chars-transform.js

@@ -0,0 +1,30 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+/**
+ * A regexp-tree plugin to simplify character classes
+ * spanning only one or two chars.
+ *
+ * [a-a] -> [a]
+ * [a-b] -> [ab]
+ */
+
+module.exports = {
+  ClassRange: function ClassRange(path) {
+    var node = path.node;
+
+
+    if (node.from.codePoint === node.to.codePoint) {
+
+      path.replace(node.from);
+    } else if (node.from.codePoint === node.to.codePoint - 1) {
+
+      path.getParent().insertChildAt(node.to, path.index + 1);
+      path.replace(node.from);
+    }
+  }
+};

node_modules/regexp-tree/dist/optimizer/transforms/char-class-remove-duplicates-transform.js

@@ -0,0 +1,33 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+/**
+ * A regexp-tree plugin to remove duplicates from character classes.
+ */
+
+module.exports = {
+  CharacterClass: function CharacterClass(path) {
+    var node = path.node;
+
+    var sources = {};
+
+    for (var i = 0; i < node.expressions.length; i++) {
+      var childPath = path.getChild(i);
+      var source = childPath.jsonEncode();
+
+      if (sources.hasOwnProperty(source)) {
+        childPath.remove();
+
+        // Since we remove the current node.
+        // TODO: make it simpler for users with a method.
+        i--;
+      }
+
+      sources[source] = true;
+    }
+  }
+};

node_modules/regexp-tree/dist/optimizer/transforms/char-class-to-meta-transform.js

@@ -0,0 +1,211 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+/**
+ * A regexp-tree plugin to replace standard character classes with
+ * their meta symbols equivalents.
+ */
+
+module.exports = {
+  _hasIFlag: false,
+  _hasUFlag: false,
+  init: function init(ast) {
+    this._hasIFlag = ast.flags.includes('i');
+    this._hasUFlag = ast.flags.includes('u');
+  },
+  CharacterClass: function CharacterClass(path) {
+
+    // [0-9] -> \d
+    rewriteNumberRanges(path);
+
+    // [a-zA-Z_0-9] -> \w
+    rewriteWordRanges(path, this._hasIFlag, this._hasUFlag);
+
+    // [ \t\r\n\f] -> \s
+    rewriteWhitespaceRanges(path);
+  }
+};
+
+/**
+ * Rewrites number ranges: [0-9] -> \d
+ */
+function rewriteNumberRanges(path) {
+  var node = path.node;
+
+
+  node.expressions.forEach(function (expression, i) {
+    if (isFullNumberRange(expression)) {
+      path.getChild(i).replace({
+        type: 'Char',
+        value: '\\d',
+        kind: 'meta'
+      });
+    }
+  });
+}
+
+/**
+ * Rewrites word ranges: [a-zA-Z_0-9] -> \w
+ * Thus, the ranges may go in any order, and other symbols/ranges
+ * are kept untouched, e.g. [a-z_\dA-Z$] -> [\w$]
+ */
+function rewriteWordRanges(path, hasIFlag, hasUFlag) {
+  var node = path.node;
+
+
+  var numberPath = null;
+  var lowerCasePath = null;
+  var upperCasePath = null;
+  var underscorePath = null;
+  var u017fPath = null;
+  var u212aPath = null;
+
+  node.expressions.forEach(function (expression, i) {
+
+    // \d
+    if (isMetaChar(expression, '\\d')) {
+      numberPath = path.getChild(i);
+    }
+
+    // a-z
+    else if (isLowerCaseRange(expression)) {
+        lowerCasePath = path.getChild(i);
+      }
+
+      // A-Z
+      else if (isUpperCaseRange(expression)) {
+          upperCasePath = path.getChild(i);
+        }
+
+        // _
+        else if (isUnderscore(expression)) {
+            underscorePath = path.getChild(i);
+          } else if (hasIFlag && hasUFlag && isU017fPath(expression)) {
+            u017fPath = path.getChild(i);
+          } else if (hasIFlag && hasUFlag && isU212aPath(expression)) {
+            u212aPath = path.getChild(i);
+          }
+  });
+
+  // If we found the whole pattern, replace it.
+  if (numberPath && (lowerCasePath && upperCasePath || hasIFlag && (lowerCasePath || upperCasePath)) && underscorePath && (!hasUFlag || !hasIFlag || u017fPath && u212aPath)) {
+
+    // Put \w in place of \d.
+    numberPath.replace({
+      type: 'Char',
+      value: '\\w',
+      kind: 'meta'
+    });
+
+    // Other paths are removed.
+    if (lowerCasePath) {
+      lowerCasePath.remove();
+    }
+    if (upperCasePath) {
+      upperCasePath.remove();
+    }
+    underscorePath.remove();
+    if (u017fPath) {
+      u017fPath.remove();
+    }
+    if (u212aPath) {
+      u212aPath.remove();
+    }
+  }
+}
+
+/**
+ * Rewrites whitespace ranges: [ \t\r\n\f] -> \s.
+ */
+function rewriteWhitespaceRanges(path) {
+  var node = path.node;
+
+
+  var spacePath = null;
+  var tPath = null;
+  var nPath = null;
+  var rPath = null;
+  var fPath = null;
+
+  node.expressions.forEach(function (expression, i) {
+
+    // Space
+    if (isChar(expression, ' ')) {
+      spacePath = path.getChild(i);
+    }
+
+    // \t
+    else if (isMetaChar(expression, '\\t')) {
+        tPath = path.getChild(i);
+      }
+
+      // \n
+      else if (isMetaChar(expression, '\\n')) {
+          nPath = path.getChild(i);
+        }
+
+        // \r
+        else if (isMetaChar(expression, '\\r')) {
+            rPath = path.getChild(i);
+          }
+
+          // \f
+          else if (isMetaChar(expression, '\\f')) {
+              fPath = path.getChild(i);
+            }
+  });
+
+  // If we found the whole pattern, replace it.
+  // Make \f optional.
+  if (spacePath && tPath && nPath && rPath) {
+
+    // Put \s in place of \n.
+    nPath.node.value = '\\s';
+
+    // Other paths are removed.
+    spacePath.remove();
+    tPath.remove();
+    rPath.remove();
+
+    if (fPath) {
+      fPath.remove();
+    }
+  }
+}
+
+function isFullNumberRange(node) {
+  return node.type === 'ClassRange' && node.from.value === '0' && node.to.value === '9';
+}
+
+function isChar(node, value) {
+  var kind = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : 'simple';
+
+  return node.type === 'Char' && node.value === value && node.kind === kind;
+}
+
+function isMetaChar(node, value) {
+  return isChar(node, value, 'meta');
+}
+
+function isLowerCaseRange(node) {
+  return node.type === 'ClassRange' && node.from.value === 'a' && node.to.value === 'z';
+}
+
+function isUpperCaseRange(node) {
+  return node.type === 'ClassRange' && node.from.value === 'A' && node.to.value === 'Z';
+}
+
+function isUnderscore(node) {
+  return node.type === 'Char' && node.value === '_' && node.kind === 'simple';
+}
+
+function isU017fPath(node) {
+  return node.type === 'Char' && node.kind === 'unicode' && node.codePoint === 0x017f;
+}
+function isU212aPath(node) {
+  return node.type === 'Char' && node.kind === 'unicode' && node.codePoint === 0x212a;
+}

node_modules/regexp-tree/dist/optimizer/transforms/char-class-to-single-char-transform.js

@@ -0,0 +1,71 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+/**
+ * A regexp-tree plugin to replace single char character classes with
+ * just that character.
+ *
+ * [\d] -> \d, [^\w] -> \W
+ */
+
+module.exports = {
+  CharacterClass: function CharacterClass(path) {
+    var node = path.node;
+
+
+    if (node.expressions.length !== 1 || !isAppropriateChar(node.expressions[0])) {
+      return;
+    }
+
+    var _node$expressions$ = node.expressions[0],
+        value = _node$expressions$.value,
+        kind = _node$expressions$.kind,
+        escaped = _node$expressions$.escaped;
+
+
+    if (node.negative) {
+      // For negative can extract only meta chars like [^\w] -> \W
+      // cannot do for [^a] -> a (wrong).
+      if (!isMeta(value)) {
+        return;
+      }
+
+      value = getInverseMeta(value);
+    }
+
+    path.replace({
+      type: 'Char',
+      value: value,
+      kind: kind,
+      escaped: escaped || shouldEscape(value)
+    });
+  }
+};
+
+function isAppropriateChar(node) {
+  return node.type === 'Char' &&
+  // We don't extract [\b] (backspace) since \b has different
+  // semantics (word boundary).
+  node.value !== '\\b';
+}
+
+function isMeta(value) {
+  return (/^\\[dwsDWS]$/.test(value)
+  );
+}
+
+function getInverseMeta(value) {
+  return (/[dws]/.test(value) ? value.toUpperCase() : value.toLowerCase()
+  );
+}
+
+// Note: \{ and \} are always preserved to avoid `a[{]2[}]` turning
+// into `a{2}`.
+function shouldEscape(value) {
+  return (/[*[()+?$./{}|]/.test(value)
+  );
+}

node_modules/regexp-tree/dist/optimizer/transforms/char-code-to-simple-char-transform.js

@@ -0,0 +1,84 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+var UPPER_A_CP = 'A'.codePointAt(0);
+var UPPER_Z_CP = 'Z'.codePointAt(0);
+var LOWER_A_CP = 'a'.codePointAt(0);
+var LOWER_Z_CP = 'z'.codePointAt(0);
+var DIGIT_0_CP = '0'.codePointAt(0);
+var DIGIT_9_CP = '9'.codePointAt(0);
+
+/**
+ * A regexp-tree plugin to transform coded chars into simple chars.
+ *
+ * \u0061 -> a
+ */
+module.exports = {
+  Char: function Char(path) {
+    var node = path.node,
+        parent = path.parent;
+
+    if (isNaN(node.codePoint) || node.kind === 'simple') {
+      return;
+    }
+
+    if (parent.type === 'ClassRange') {
+      if (!isSimpleRange(parent)) {
+        return;
+      }
+    }
+
+    if (!isPrintableASCIIChar(node.codePoint)) {
+      return;
+    }
+
+    var symbol = String.fromCodePoint(node.codePoint);
+    var newChar = {
+      type: 'Char',
+      kind: 'simple',
+      value: symbol,
+      symbol: symbol,
+      codePoint: node.codePoint
+    };
+    if (needsEscape(symbol, parent.type)) {
+      newChar.escaped = true;
+    }
+    path.replace(newChar);
+  }
+};
+
+/**
+ * Checks if a range is included either in 0-9, a-z or A-Z
+ * @param classRange
+ * @returns {boolean}
+ */
+function isSimpleRange(classRange) {
+  var from = classRange.from,
+      to = classRange.to;
+
+  return from.codePoint >= DIGIT_0_CP && from.codePoint <= DIGIT_9_CP && to.codePoint >= DIGIT_0_CP && to.codePoint <= DIGIT_9_CP || from.codePoint >= UPPER_A_CP && from.codePoint <= UPPER_Z_CP && to.codePoint >= UPPER_A_CP && to.codePoint <= UPPER_Z_CP || from.codePoint >= LOWER_A_CP && from.codePoint <= LOWER_Z_CP && to.codePoint >= LOWER_A_CP && to.codePoint <= LOWER_Z_CP;
+}
+
+/**
+ * Checks if a code point in the range of printable ASCII chars
+ * (DEL char excluded)
+ * @param codePoint
+ * @returns {boolean}
+ */
+function isPrintableASCIIChar(codePoint) {
+  return codePoint >= 0x20 && codePoint <= 0x7e;
+}
+
+function needsEscape(symbol, parentType) {
+  if (parentType === 'ClassRange' || parentType === 'CharacterClass') {
+    return (/[\]\\^-]/.test(symbol)
+    );
+  }
+
+  return (/[*[()+?^$./\\|{}]/.test(symbol)
+  );
+}

node_modules/regexp-tree/dist/optimizer/transforms/char-escape-unescape-transform.js

@@ -0,0 +1,143 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+/**
+ * A regexp-tree plugin to remove unnecessary escape.
+ *
+ * \e -> e
+ *
+ * [\(] -> [(]
+ */
+
+module.exports = {
+  _hasXFlag: false,
+  init: function init(ast) {
+    this._hasXFlag = ast.flags.includes('x');
+  },
+  Char: function Char(path) {
+    var node = path.node;
+
+
+    if (!node.escaped) {
+      return;
+    }
+
+    if (shouldUnescape(path, this._hasXFlag)) {
+      delete node.escaped;
+    }
+  }
+};
+
+function shouldUnescape(path, hasXFlag) {
+  var value = path.node.value,
+      index = path.index,
+      parent = path.parent;
+
+  // In char class (, etc are allowed.
+
+  if (parent.type !== 'CharacterClass' && parent.type !== 'ClassRange') {
+    return !preservesEscape(value, index, parent, hasXFlag);
+  }
+
+  return !preservesInCharClass(value, index, parent);
+}
+
+/**
+ * \], \\, \^, \-
+ */
+function preservesInCharClass(value, index, parent) {
+  if (value === '^') {
+    // Avoid [\^a] turning into [^a]
+    return index === 0 && !parent.negative;
+  }
+  if (value === '-') {
+    // Avoid [a\-z] turning into [a-z]
+    return index !== 0 && index !== parent.expressions.length - 1;
+  }
+  return (/[\]\\]/.test(value)
+  );
+}
+
+function preservesEscape(value, index, parent, hasXFlag) {
+  if (value === '{') {
+    return preservesOpeningCurlyBraceEscape(index, parent);
+  }
+
+  if (value === '}') {
+    return preservesClosingCurlyBraceEscape(index, parent);
+  }
+
+  if (hasXFlag && /[ #]/.test(value)) {
+    return true;
+  }
+
+  return (/[*[()+?^$./\\|]/.test(value)
+  );
+}
+
+function consumeNumbers(startIndex, parent, rtl) {
+  var i = startIndex;
+  var siblingNode = (rtl ? i >= 0 : i < parent.expressions.length) && parent.expressions[i];
+
+  while (siblingNode && siblingNode.type === 'Char' && siblingNode.kind === 'simple' && !siblingNode.escaped && /\d/.test(siblingNode.value)) {
+    rtl ? i-- : i++;
+    siblingNode = (rtl ? i >= 0 : i < parent.expressions.length) && parent.expressions[i];
+  }
+
+  return Math.abs(startIndex - i);
+}
+
+function isSimpleChar(node, value) {
+  return node && node.type === 'Char' && node.kind === 'simple' && !node.escaped && node.value === value;
+}
+
+function preservesOpeningCurlyBraceEscape(index, parent) {
+  var nbFollowingNumbers = consumeNumbers(index + 1, parent);
+  var i = index + nbFollowingNumbers + 1;
+  var nextSiblingNode = i < parent.expressions.length && parent.expressions[i];
+
+  if (nbFollowingNumbers) {
+
+    // Avoid \{3} turning into {3}
+    if (isSimpleChar(nextSiblingNode, '}')) {
+      return true;
+    }
+
+    if (isSimpleChar(nextSiblingNode, ',')) {
+
+      nbFollowingNumbers = consumeNumbers(i + 1, parent);
+      i = i + nbFollowingNumbers + 1;
+      nextSiblingNode = i < parent.expressions.length && parent.expressions[i];
+
+      // Avoid \{3,} turning into {3,}
+      return isSimpleChar(nextSiblingNode, '}');
+    }
+  }
+  return false;
+}
+
+function preservesClosingCurlyBraceEscape(index, parent) {
+  var nbPrecedingNumbers = consumeNumbers(index - 1, parent, true);
+  var i = index - nbPrecedingNumbers - 1;
+  var previousSiblingNode = i >= 0 && parent.expressions[i];
+
+  // Avoid {3\} turning into {3}
+  if (nbPrecedingNumbers && isSimpleChar(previousSiblingNode, '{')) {
+    return true;
+  }
+
+  if (isSimpleChar(previousSiblingNode, ',')) {
+
+    nbPrecedingNumbers = consumeNumbers(i - 1, parent, true);
+    i = i - nbPrecedingNumbers - 1;
+    previousSiblingNode = i < parent.expressions.length && parent.expressions[i];
+
+    // Avoid {3,\} turning into {3,}
+    return nbPrecedingNumbers && isSimpleChar(previousSiblingNode, '{');
+  }
+  return false;
+}

node_modules/regexp-tree/dist/optimizer/transforms/char-surrogate-pair-to-single-unicode-transform.js

@@ -0,0 +1,27 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+/**
+ * A regexp-tree plugin to transform surrogate pairs into single unicode code point
+ *
+ * \ud83d\ude80 -> \u{1f680}
+ */
+
+module.exports = {
+  shouldRun: function shouldRun(ast) {
+    return ast.flags.includes('u');
+  },
+  Char: function Char(path) {
+    var node = path.node;
+
+    if (node.kind !== 'unicode' || !node.isSurrogatePair || isNaN(node.codePoint)) {
+      return;
+    }
+    node.value = '\\u{' + node.codePoint.toString(16) + '}';
+    delete node.isSurrogatePair;
+  }
+};

node_modules/regexp-tree/dist/optimizer/transforms/combine-repeating-patterns-transform.js

@@ -0,0 +1,195 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+function _toConsumableArray(arr) { if (Array.isArray(arr)) { for (var i = 0, arr2 = Array(arr.length); i < arr.length; i++) { arr2[i] = arr[i]; } return arr2; } else { return Array.from(arr); } }
+
+var NodePath = require('../../traverse/node-path');
+
+var _require = require('../../transform/utils'),
+    increaseQuantifierByOne = _require.increaseQuantifierByOne;
+
+/**
+ * A regexp-tree plugin to combine repeating patterns.
+ *
+ * /^abcabcabc/ -> /^abc{3}/
+ * /^(?:abc){2}abc/ -> /^(?:abc){3}/
+ * /^abc(?:abc){2}/ -> /^(?:abc){3}/
+ */
+
+module.exports = {
+  Alternative: function Alternative(path) {
+    var node = path.node;
+
+    // We can skip the first child
+
+    var index = 1;
+    while (index < node.expressions.length) {
+      var child = path.getChild(index);
+      index = Math.max(1, combineRepeatingPatternLeft(path, child, index));
+
+      if (index >= node.expressions.length) {
+        break;
+      }
+
+      child = path.getChild(index);
+      index = Math.max(1, combineWithPreviousRepetition(path, child, index));
+
+      if (index >= node.expressions.length) {
+        break;
+      }
+
+      child = path.getChild(index);
+      index = Math.max(1, combineRepetitionWithPrevious(path, child, index));
+
+      index++;
+    }
+  }
+};
+
+// abcabc -> (?:abc){2}
+function combineRepeatingPatternLeft(alternative, child, index) {
+  var node = alternative.node;
+
+
+  var nbPossibleLengths = Math.ceil(index / 2);
+  var i = 0;
+
+  while (i < nbPossibleLengths) {
+    var startIndex = index - 2 * i - 1;
+    var right = void 0,
+        left = void 0;
+
+    if (i === 0) {
+      right = child;
+      left = alternative.getChild(startIndex);
+    } else {
+      right = NodePath.getForNode({
+        type: 'Alternative',
+        expressions: [].concat(_toConsumableArray(node.expressions.slice(index - i, index)), [child.node])
+      });
+
+      left = NodePath.getForNode({
+        type: 'Alternative',
+        expressions: [].concat(_toConsumableArray(node.expressions.slice(startIndex, index - i)))
+      });
+    }
+
+    if (right.hasEqualSource(left)) {
+      for (var j = 0; j < 2 * i + 1; j++) {
+        alternative.getChild(startIndex).remove();
+      }
+
+      child.replace({
+        type: 'Repetition',
+        expression: i === 0 ? right.node : {
+          type: 'Group',
+          capturing: false,
+          expression: right.node
+        },
+        quantifier: {
+          type: 'Quantifier',
+          kind: 'Range',
+          from: 2,
+          to: 2,
+          greedy: true
+        }
+      });
+      return startIndex;
+    }
+
+    i++;
+  }
+
+  return index;
+}
+
+// (?:abc){2}abc -> (?:abc){3}
+function combineWithPreviousRepetition(alternative, child, index) {
+  var node = alternative.node;
+
+
+  var i = 0;
+  while (i < index) {
+    var previousChild = alternative.getChild(i);
+
+    if (previousChild.node.type === 'Repetition' && previousChild.node.quantifier.greedy) {
+      var left = previousChild.getChild();
+      var right = void 0;
+
+      if (left.node.type === 'Group' && !left.node.capturing) {
+        left = left.getChild();
+      }
+
+      if (i + 1 === index) {
+        right = child;
+        if (right.node.type === 'Group' && !right.node.capturing) {
+          right = right.getChild();
+        }
+      } else {
+        right = NodePath.getForNode({
+          type: 'Alternative',
+          expressions: [].concat(_toConsumableArray(node.expressions.slice(i + 1, index + 1)))
+        });
+      }
+
+      if (left.hasEqualSource(right)) {
+
+        for (var j = i; j < index; j++) {
+          alternative.getChild(i + 1).remove();
+        }
+
+        increaseQuantifierByOne(previousChild.node.quantifier);
+
+        return i;
+      }
+    }
+
+    i++;
+  }
+  return index;
+}
+
+// abc(?:abc){2} -> (?:abc){3}
+function combineRepetitionWithPrevious(alternative, child, index) {
+  var node = alternative.node;
+
+
+  if (child.node.type === 'Repetition' && child.node.quantifier.greedy) {
+    var right = child.getChild();
+    var left = void 0;
+
+    if (right.node.type === 'Group' && !right.node.capturing) {
+      right = right.getChild();
+    }
+
+    var rightLength = void 0;
+    if (right.node.type === 'Alternative') {
+      rightLength = right.node.expressions.length;
+      left = NodePath.getForNode({
+        type: 'Alternative',
+        expressions: [].concat(_toConsumableArray(node.expressions.slice(index - rightLength, index)))
+      });
+    } else {
+      rightLength = 1;
+      left = alternative.getChild(index - 1);
+      if (left.node.type === 'Group' && !left.node.capturing) {
+        left = left.getChild();
+      }
+    }
+
+    if (left.hasEqualSource(right)) {
+      for (var j = index - rightLength; j < index; j++) {
+        alternative.getChild(index - rightLength).remove();
+      }
+
+      increaseQuantifierByOne(child.node.quantifier);
+
+      return index - rightLength;
+    }
+  }
+  return index;
+}

node_modules/regexp-tree/dist/optimizer/transforms/disjunction-remove-duplicates-transform.js

@@ -0,0 +1,44 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+var NodePath = require('../../traverse/node-path');
+
+var _require = require('../../transform/utils'),
+    disjunctionToList = _require.disjunctionToList,
+    listToDisjunction = _require.listToDisjunction;
+
+/**
+ * Removes duplicates from a disjunction sequence:
+ *
+ * /(ab|bc|ab)+(xy|xy)+/ -> /(ab|bc)+(xy)+/
+ */
+
+
+module.exports = {
+  Disjunction: function Disjunction(path) {
+    var node = path.node;
+
+    // Make unique nodes.
+
+    var uniqueNodesMap = {};
+
+    var parts = disjunctionToList(node).filter(function (part) {
+      var encoded = part ? NodePath.getForNode(part).jsonEncode() : 'null';
+
+      // Already recorded this part, filter out.
+      if (uniqueNodesMap.hasOwnProperty(encoded)) {
+        return false;
+      }
+
+      uniqueNodesMap[encoded] = part;
+      return true;
+    });
+
+    // Replace with the optimized disjunction.
+    path.replace(listToDisjunction(parts));
+  }
+};

node_modules/regexp-tree/dist/optimizer/transforms/group-single-chars-to-char-class.js

@@ -0,0 +1,92 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+/**
+ * A regexp-tree plugin to replace single char group disjunction to char group
+ *
+ * a|b|c -> [abc]
+ * [12]|3|4 -> [1234]
+ * (a|b|c) -> ([abc])
+ * (?:a|b|c) -> [abc]
+ */
+
+module.exports = {
+  Disjunction: function Disjunction(path) {
+    var node = path.node,
+        parent = path.parent;
+
+
+    if (!handlers[parent.type]) {
+      return;
+    }
+
+    var charset = new Map();
+
+    if (!shouldProcess(node, charset) || !charset.size) {
+      return;
+    }
+
+    var characterClass = {
+      type: 'CharacterClass',
+      expressions: Array.from(charset.keys()).sort().map(function (key) {
+        return charset.get(key);
+      })
+    };
+
+    handlers[parent.type](path.getParent(), characterClass);
+  }
+};
+
+var handlers = {
+  RegExp: function RegExp(path, characterClass) {
+    var node = path.node;
+
+
+    node.body = characterClass;
+  },
+  Group: function Group(path, characterClass) {
+    var node = path.node;
+
+
+    if (node.capturing) {
+      node.expression = characterClass;
+    } else {
+      path.replace(characterClass);
+    }
+  }
+};
+
+function shouldProcess(expression, charset) {
+  if (!expression) {
+    // Abort on empty disjunction part
+    return false;
+  }
+
+  var type = expression.type;
+
+
+  if (type === 'Disjunction') {
+    var left = expression.left,
+        right = expression.right;
+
+
+    return shouldProcess(left, charset) && shouldProcess(right, charset);
+  } else if (type === 'Char') {
+    var value = expression.value;
+
+
+    charset.set(value, expression);
+
+    return true;
+  } else if (type === 'CharacterClass') {
+    return expression.expressions.every(function (expression) {
+      return shouldProcess(expression, charset);
+    });
+  }
+
+  return false;
+}

node_modules/regexp-tree/dist/optimizer/transforms/index.js

@@ -0,0 +1,56 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+module.exports = {
+  // \ud83d\ude80 -> \u{1f680}
+  'charSurrogatePairToSingleUnicode': require('./char-surrogate-pair-to-single-unicode-transform'),
+
+  // \u0061 -> a
+  'charCodeToSimpleChar': require('./char-code-to-simple-char-transform'),
+
+  // /Aa/i -> /aa/i
+  'charCaseInsensitiveLowerCaseTransform': require('./char-case-insensitive-lowercase-transform'),
+
+  // [\d\d] -> [\d]
+  'charClassRemoveDuplicates': require('./char-class-remove-duplicates-transform'),
+
+  // a{1,2}a{2,3} -> a{3,5}
+  'quantifiersMerge': require('./quantifiers-merge-transform'),
+
+  // a{1,} -> a+, a{3,3} -> a{3}, a{1} -> a
+  'quantifierRangeToSymbol': require('./quantifier-range-to-symbol-transform'),
+
+  // [a-a] -> [a], [a-b] -> [ab]
+  'charClassClassrangesToChars': require('./char-class-classranges-to-chars-transform'),
+
+  // [a-de-f] -> [a-f]
+  'charClassClassrangesMerge': require('./char-class-classranges-merge-transform'),
+
+  // [0-9] -> [\d]
+  'charClassToMeta': require('./char-class-to-meta-transform'),
+
+  // [\d] -> \d, [^\w] -> \W
+  'charClassToSingleChar': require('./char-class-to-single-char-transform'),
+
+  // \e -> e
+  'charEscapeUnescape': require('./char-escape-unescape-transform'),
+
+  // (ab|ab) -> (ab)
+  'disjunctionRemoveDuplicates': require('./disjunction-remove-duplicates-transform'),
+
+  // (a|b|c) -> [abc]
+  'groupSingleCharsToCharClass': require('./group-single-chars-to-char-class'),
+
+  // (?:)a -> a
+  'removeEmptyGroup': require('./remove-empty-group-transform'),
+
+  // (?:a) -> a
+  'ungroup': require('./ungroup-transform'),
+
+  // abcabcabc -> (?:abc){3}
+  'combineRepeatingPatterns': require('./combine-repeating-patterns-transform')
+};

node_modules/regexp-tree/dist/optimizer/transforms/quantifier-range-to-symbol-transform.js

@@ -0,0 +1,74 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+/**
+ * A regexp-tree plugin to replace different range-based quantifiers
+ * with their symbol equivalents.
+ *
+ * a{0,} -> a*
+ * a{1,} -> a+
+ * a{1} -> a
+ *
+ * NOTE: the following is automatically handled in the generator:
+ *
+ * a{3,3} -> a{3}
+ */
+
+module.exports = {
+  Quantifier: function Quantifier(path) {
+    var node = path.node;
+
+
+    if (node.kind !== 'Range') {
+      return;
+    }
+
+    // a{0,} -> a*
+    rewriteOpenZero(path);
+
+    // a{1,} -> a+
+    rewriteOpenOne(path);
+
+    // a{1} -> a
+    rewriteExactOne(path);
+  }
+};
+
+function rewriteOpenZero(path) {
+  var node = path.node;
+
+
+  if (node.from !== 0 || node.to) {
+    return;
+  }
+
+  node.kind = '*';
+  delete node.from;
+}
+
+function rewriteOpenOne(path) {
+  var node = path.node;
+
+
+  if (node.from !== 1 || node.to) {
+    return;
+  }
+
+  node.kind = '+';
+  delete node.from;
+}
+
+function rewriteExactOne(path) {
+  var node = path.node;
+
+
+  if (node.from !== 1 || node.to !== 1) {
+    return;
+  }
+
+  path.parentPath.replace(path.parentPath.node.expression);
+}

node_modules/regexp-tree/dist/optimizer/transforms/quantifiers-merge-transform.js

@@ -0,0 +1,113 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+var _require = require('../../transform/utils'),
+    increaseQuantifierByOne = _require.increaseQuantifierByOne;
+
+/**
+ * A regexp-tree plugin to merge quantifiers
+ *
+ * a+a+ -> a{2,}
+ * a{2}a{3} -> a{5}
+ * a{1,2}a{2,3} -> a{3,5}
+ */
+
+
+module.exports = {
+  Repetition: function Repetition(path) {
+    var node = path.node,
+        parent = path.parent;
+
+
+    if (parent.type !== 'Alternative' || !path.index) {
+      return;
+    }
+
+    var previousSibling = path.getPreviousSibling();
+
+    if (!previousSibling) {
+      return;
+    }
+
+    if (previousSibling.node.type === 'Repetition') {
+      if (!previousSibling.getChild().hasEqualSource(path.getChild())) {
+        return;
+      }
+
+      var _extractFromTo = extractFromTo(previousSibling.node.quantifier),
+          previousSiblingFrom = _extractFromTo.from,
+          previousSiblingTo = _extractFromTo.to;
+
+      var _extractFromTo2 = extractFromTo(node.quantifier),
+          nodeFrom = _extractFromTo2.from,
+          nodeTo = _extractFromTo2.to;
+
+      // It's does not seem reliable to merge quantifiers with different greediness
+      // when none of both is a greedy open range
+
+
+      if (previousSibling.node.quantifier.greedy !== node.quantifier.greedy && !isGreedyOpenRange(previousSibling.node.quantifier) && !isGreedyOpenRange(node.quantifier)) {
+        return;
+      }
+
+      // a*a* -> a*
+      // a*a+ -> a+
+      // a+a+ -> a{2,}
+      // a{2}a{4} -> a{6}
+      // a{1,2}a{2,3} -> a{3,5}
+      // a{1,}a{2,} -> a{3,}
+      // a+a{2,} -> a{3,}
+
+      // a??a{2,} -> a{2,}
+      // a*?a{2,} -> a{2,}
+      // a+?a{2,} -> a{3,}
+
+      node.quantifier.kind = 'Range';
+      node.quantifier.from = previousSiblingFrom + nodeFrom;
+      if (previousSiblingTo && nodeTo) {
+        node.quantifier.to = previousSiblingTo + nodeTo;
+      } else {
+        delete node.quantifier.to;
+      }
+      if (isGreedyOpenRange(previousSibling.node.quantifier) || isGreedyOpenRange(node.quantifier)) {
+        node.quantifier.greedy = true;
+      }
+
+      previousSibling.remove();
+    } else {
+      if (!previousSibling.hasEqualSource(path.getChild())) {
+        return;
+      }
+
+      increaseQuantifierByOne(node.quantifier);
+      previousSibling.remove();
+    }
+  }
+};
+
+function isGreedyOpenRange(quantifier) {
+  return quantifier.greedy && (quantifier.kind === '+' || quantifier.kind === '*' || quantifier.kind === 'Range' && !quantifier.to);
+}
+
+function extractFromTo(quantifier) {
+  var from = void 0,
+      to = void 0;
+  if (quantifier.kind === '*') {
+    from = 0;
+  } else if (quantifier.kind === '+') {
+    from = 1;
+  } else if (quantifier.kind === '?') {
+    from = 0;
+    to = 1;
+  } else {
+    from = quantifier.from;
+    if (quantifier.to) {
+      to = quantifier.to;
+    }
+  }
+  return { from: from, to: to };
+}

node_modules/regexp-tree/dist/optimizer/transforms/remove-empty-group-transform.js

@@ -0,0 +1,34 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+/**
+ * A regexp-tree plugin to remove non-capturing empty groups.
+ *
+ * /(?:)a/ -> /a/
+ * /a|(?:)/ -> /a|/
+ */
+
+module.exports = {
+  Group: function Group(path) {
+    var node = path.node,
+        parent = path.parent;
+
+    var childPath = path.getChild();
+
+    if (node.capturing || childPath) {
+      return;
+    }
+
+    if (parent.type === 'Repetition') {
+
+      path.getParent().replace(node);
+    } else if (parent.type !== 'RegExp') {
+
+      path.remove();
+    }
+  }
+};

node_modules/regexp-tree/dist/optimizer/transforms/ungroup-transform.js

@@ -0,0 +1,55 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+/**
+ * A regexp-tree plugin to remove unnecessary groups.
+ *
+ * /(?:a)/ -> /a/
+ */
+
+function _toConsumableArray(arr) { if (Array.isArray(arr)) { for (var i = 0, arr2 = Array(arr.length); i < arr.length; i++) { arr2[i] = arr[i]; } return arr2; } else { return Array.from(arr); } }
+
+module.exports = {
+  Group: function Group(path) {
+    var node = path.node,
+        parent = path.parent;
+
+    var childPath = path.getChild();
+
+    if (node.capturing || !childPath) {
+      return;
+    }
+
+    // Don't optimize /a(?:b|c)/ to /ab|c/
+    // but /(?:b|c)/ to /b|c/ is ok
+    if (childPath.node.type === 'Disjunction' && parent.type !== 'RegExp') {
+      return;
+    }
+
+    // Don't optimize /(?:ab)+/ to /ab+/
+    // but /(?:a)+/ to /a+/ is ok
+    // and /(?:[a-d])+/ to /[a-d]+/ is ok too
+    if (parent.type === 'Repetition' && childPath.node.type !== 'Char' && childPath.node.type !== 'CharacterClass') {
+      return;
+    }
+
+    if (childPath.node.type === 'Alternative') {
+      var parentPath = path.getParent();
+      if (parentPath.node.type === 'Alternative') {
+
+        // /abc(?:def)ghi/ When (?:def) is ungrouped its content must be merged with parent alternative
+
+        parentPath.replace({
+          type: 'Alternative',
+          expressions: [].concat(_toConsumableArray(parent.expressions.slice(0, path.index)), _toConsumableArray(childPath.node.expressions), _toConsumableArray(parent.expressions.slice(path.index + 1)))
+        });
+      }
+    } else {
+      path.replace(childPath.node);
+    }
+  }
+};

node_modules/regexp-tree/dist/parser/index.js

@@ -0,0 +1,28 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+var regexpTreeParser = require('./generated/regexp-tree');
+
+/**
+ * Original parse function.
+ */
+var generatedParseFn = regexpTreeParser.parse.bind(regexpTreeParser);
+
+/**
+ * Parses a regular expression.
+ *
+ * Override original `regexpTreeParser.parse` to convert a value to a string,
+ * since in regexp-tree we may pass strings, and RegExp instance.
+ */
+regexpTreeParser.parse = function (regexp, options) {
+  return generatedParseFn('' + regexp, options);
+};
+
+// By default do not capture locations; callers may override.
+regexpTreeParser.setOptions({ captureLocations: false });
+
+module.exports = regexpTreeParser;

node_modules/regexp-tree/dist/parser/unicode/parser-unicode-properties.js

@@ -0,0 +1,379 @@
+'use strict';
+
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+var NON_BINARY_PROP_NAMES_TO_ALIASES = {
+  General_Category: 'gc',
+  Script: 'sc',
+  Script_Extensions: 'scx'
+};
+
+var NON_BINARY_ALIASES_TO_PROP_NAMES = inverseMap(NON_BINARY_PROP_NAMES_TO_ALIASES);
+
+var BINARY_PROP_NAMES_TO_ALIASES = {
+  ASCII: 'ASCII',
+  ASCII_Hex_Digit: 'AHex',
+  Alphabetic: 'Alpha',
+  Any: 'Any',
+  Assigned: 'Assigned',
+  Bidi_Control: 'Bidi_C',
+  Bidi_Mirrored: 'Bidi_M',
+  Case_Ignorable: 'CI',
+  Cased: 'Cased',
+  Changes_When_Casefolded: 'CWCF',
+  Changes_When_Casemapped: 'CWCM',
+  Changes_When_Lowercased: 'CWL',
+  Changes_When_NFKC_Casefolded: 'CWKCF',
+  Changes_When_Titlecased: 'CWT',
+  Changes_When_Uppercased: 'CWU',
+  Dash: 'Dash',
+  Default_Ignorable_Code_Point: 'DI',
+  Deprecated: 'Dep',
+  Diacritic: 'Dia',
+  Emoji: 'Emoji',
+  Emoji_Component: 'Emoji_Component',
+  Emoji_Modifier: 'Emoji_Modifier',
+  Emoji_Modifier_Base: 'Emoji_Modifier_Base',
+  Emoji_Presentation: 'Emoji_Presentation',
+  Extended_Pictographic: 'Extended_Pictographic',
+  Extender: 'Ext',
+  Grapheme_Base: 'Gr_Base',
+  Grapheme_Extend: 'Gr_Ext',
+  Hex_Digit: 'Hex',
+  IDS_Binary_Operator: 'IDSB',
+  IDS_Trinary_Operator: 'IDST',
+  ID_Continue: 'IDC',
+  ID_Start: 'IDS',
+  Ideographic: 'Ideo',
+  Join_Control: 'Join_C',
+  Logical_Order_Exception: 'LOE',
+  Lowercase: 'Lower',
+  Math: 'Math',
+  Noncharacter_Code_Point: 'NChar',
+  Pattern_Syntax: 'Pat_Syn',
+  Pattern_White_Space: 'Pat_WS',
+  Quotation_Mark: 'QMark',
+  Radical: 'Radical',
+  Regional_Indicator: 'RI',
+  Sentence_Terminal: 'STerm',
+  Soft_Dotted: 'SD',
+  Terminal_Punctuation: 'Term',
+  Unified_Ideograph: 'UIdeo',
+  Uppercase: 'Upper',
+  Variation_Selector: 'VS',
+  White_Space: 'space',
+  XID_Continue: 'XIDC',
+  XID_Start: 'XIDS'
+};
+
+var BINARY_ALIASES_TO_PROP_NAMES = inverseMap(BINARY_PROP_NAMES_TO_ALIASES);
+
+var GENERAL_CATEGORY_VALUE_TO_ALIASES = {
+  Cased_Letter: 'LC',
+  Close_Punctuation: 'Pe',
+  Connector_Punctuation: 'Pc',
+  Control: ['Cc', 'cntrl'],
+  Currency_Symbol: 'Sc',
+  Dash_Punctuation: 'Pd',
+  Decimal_Number: ['Nd', 'digit'],
+  Enclosing_Mark: 'Me',
+  Final_Punctuation: 'Pf',
+  Format: 'Cf',
+  Initial_Punctuation: 'Pi',
+  Letter: 'L',
+  Letter_Number: 'Nl',
+  Line_Separator: 'Zl',
+  Lowercase_Letter: 'Ll',
+  Mark: ['M', 'Combining_Mark'],
+  Math_Symbol: 'Sm',
+  Modifier_Letter: 'Lm',
+  Modifier_Symbol: 'Sk',
+  Nonspacing_Mark: 'Mn',
+  Number: 'N',
+  Open_Punctuation: 'Ps',
+  Other: 'C',
+  Other_Letter: 'Lo',
+  Other_Number: 'No',
+  Other_Punctuation: 'Po',
+  Other_Symbol: 'So',
+  Paragraph_Separator: 'Zp',
+  Private_Use: 'Co',
+  Punctuation: ['P', 'punct'],
+  Separator: 'Z',
+  Space_Separator: 'Zs',
+  Spacing_Mark: 'Mc',
+  Surrogate: 'Cs',
+  Symbol: 'S',
+  Titlecase_Letter: 'Lt',
+  Unassigned: 'Cn',
+  Uppercase_Letter: 'Lu'
+};
+
+var GENERAL_CATEGORY_VALUE_ALIASES_TO_VALUES = inverseMap(GENERAL_CATEGORY_VALUE_TO_ALIASES);
+
+var SCRIPT_VALUE_TO_ALIASES = {
+  Adlam: 'Adlm',
+  Ahom: 'Ahom',
+  Anatolian_Hieroglyphs: 'Hluw',
+  Arabic: 'Arab',
+  Armenian: 'Armn',
+  Avestan: 'Avst',
+  Balinese: 'Bali',
+  Bamum: 'Bamu',
+  Bassa_Vah: 'Bass',
+  Batak: 'Batk',
+  Bengali: 'Beng',
+  Bhaiksuki: 'Bhks',
+  Bopomofo: 'Bopo',
+  Brahmi: 'Brah',
+  Braille: 'Brai',
+  Buginese: 'Bugi',
+  Buhid: 'Buhd',
+  Canadian_Aboriginal: 'Cans',
+  Carian: 'Cari',
+  Caucasian_Albanian: 'Aghb',
+  Chakma: 'Cakm',
+  Cham: 'Cham',
+  Cherokee: 'Cher',
+  Common: 'Zyyy',
+  Coptic: ['Copt', 'Qaac'],
+  Cuneiform: 'Xsux',
+  Cypriot: 'Cprt',
+  Cyrillic: 'Cyrl',
+  Deseret: 'Dsrt',
+  Devanagari: 'Deva',
+  Dogra: 'Dogr',
+  Duployan: 'Dupl',
+  Egyptian_Hieroglyphs: 'Egyp',
+  Elbasan: 'Elba',
+  Ethiopic: 'Ethi',
+  Georgian: 'Geor',
+  Glagolitic: 'Glag',
+  Gothic: 'Goth',
+  Grantha: 'Gran',
+  Greek: 'Grek',
+  Gujarati: 'Gujr',
+  Gunjala_Gondi: 'Gong',
+  Gurmukhi: 'Guru',
+  Han: 'Hani',
+  Hangul: 'Hang',
+  Hanifi_Rohingya: 'Rohg',
+  Hanunoo: 'Hano',
+  Hatran: 'Hatr',
+  Hebrew: 'Hebr',
+  Hiragana: 'Hira',
+  Imperial_Aramaic: 'Armi',
+  Inherited: ['Zinh', 'Qaai'],
+  Inscriptional_Pahlavi: 'Phli',
+  Inscriptional_Parthian: 'Prti',
+  Javanese: 'Java',
+  Kaithi: 'Kthi',
+  Kannada: 'Knda',
+  Katakana: 'Kana',
+  Kayah_Li: 'Kali',
+  Kharoshthi: 'Khar',
+  Khmer: 'Khmr',
+  Khojki: 'Khoj',
+  Khudawadi: 'Sind',
+  Lao: 'Laoo',
+  Latin: 'Latn',
+  Lepcha: 'Lepc',
+  Limbu: 'Limb',
+  Linear_A: 'Lina',
+  Linear_B: 'Linb',
+  Lisu: 'Lisu',
+  Lycian: 'Lyci',
+  Lydian: 'Lydi',
+  Mahajani: 'Mahj',
+  Makasar: 'Maka',
+  Malayalam: 'Mlym',
+  Mandaic: 'Mand',
+  Manichaean: 'Mani',
+  Marchen: 'Marc',
+  Medefaidrin: 'Medf',
+  Masaram_Gondi: 'Gonm',
+  Meetei_Mayek: 'Mtei',
+  Mende_Kikakui: 'Mend',
+  Meroitic_Cursive: 'Merc',
+  Meroitic_Hieroglyphs: 'Mero',
+  Miao: 'Plrd',
+  Modi: 'Modi',
+  Mongolian: 'Mong',
+  Mro: 'Mroo',
+  Multani: 'Mult',
+  Myanmar: 'Mymr',
+  Nabataean: 'Nbat',
+  New_Tai_Lue: 'Talu',
+  Newa: 'Newa',
+  Nko: 'Nkoo',
+  Nushu: 'Nshu',
+  Ogham: 'Ogam',
+  Ol_Chiki: 'Olck',
+  Old_Hungarian: 'Hung',
+  Old_Italic: 'Ital',
+  Old_North_Arabian: 'Narb',
+  Old_Permic: 'Perm',
+  Old_Persian: 'Xpeo',
+  Old_Sogdian: 'Sogo',
+  Old_South_Arabian: 'Sarb',
+  Old_Turkic: 'Orkh',
+  Oriya: 'Orya',
+  Osage: 'Osge',
+  Osmanya: 'Osma',
+  Pahawh_Hmong: 'Hmng',
+  Palmyrene: 'Palm',
+  Pau_Cin_Hau: 'Pauc',
+  Phags_Pa: 'Phag',
+  Phoenician: 'Phnx',
+  Psalter_Pahlavi: 'Phlp',
+  Rejang: 'Rjng',
+  Runic: 'Runr',
+  Samaritan: 'Samr',
+  Saurashtra: 'Saur',
+  Sharada: 'Shrd',
+  Shavian: 'Shaw',
+  Siddham: 'Sidd',
+  SignWriting: 'Sgnw',
+  Sinhala: 'Sinh',
+  Sogdian: 'Sogd',
+  Sora_Sompeng: 'Sora',
+  Soyombo: 'Soyo',
+  Sundanese: 'Sund',
+  Syloti_Nagri: 'Sylo',
+  Syriac: 'Syrc',
+  Tagalog: 'Tglg',
+  Tagbanwa: 'Tagb',
+  Tai_Le: 'Tale',
+  Tai_Tham: 'Lana',
+  Tai_Viet: 'Tavt',
+  Takri: 'Takr',
+  Tamil: 'Taml',
+  Tangut: 'Tang',
+  Telugu: 'Telu',
+  Thaana: 'Thaa',
+  Thai: 'Thai',
+  Tibetan: 'Tibt',
+  Tifinagh: 'Tfng',
+  Tirhuta: 'Tirh',
+  Ugaritic: 'Ugar',
+  Vai: 'Vaii',
+  Warang_Citi: 'Wara',
+  Yi: 'Yiii',
+  Zanabazar_Square: 'Zanb'
+};
+
+var SCRIPT_VALUE_ALIASES_TO_VALUE = inverseMap(SCRIPT_VALUE_TO_ALIASES);
+
+function inverseMap(data) {
+  var inverse = {};
+
+  for (var name in data) {
+    if (!data.hasOwnProperty(name)) {
+      continue;
+    }
+    var value = data[name];
+    if (Array.isArray(value)) {
+      for (var i = 0; i < value.length; i++) {
+        inverse[value[i]] = name;
+      }
+    } else {
+      inverse[value] = name;
+    }
+  }
+
+  return inverse;
+}
+
+function isValidName(name) {
+  return NON_BINARY_PROP_NAMES_TO_ALIASES.hasOwnProperty(name) || NON_BINARY_ALIASES_TO_PROP_NAMES.hasOwnProperty(name) || BINARY_PROP_NAMES_TO_ALIASES.hasOwnProperty(name) || BINARY_ALIASES_TO_PROP_NAMES.hasOwnProperty(name);
+}
+
+function isValidValue(name, value) {
+  if (isGeneralCategoryName(name)) {
+    return isGeneralCategoryValue(value);
+  }
+
+  if (isScriptCategoryName(name)) {
+    return isScriptCategoryValue(value);
+  }
+
+  return false;
+}
+
+function isAlias(name) {
+  return NON_BINARY_ALIASES_TO_PROP_NAMES.hasOwnProperty(name) || BINARY_ALIASES_TO_PROP_NAMES.hasOwnProperty(name);
+}
+
+function isGeneralCategoryName(name) {
+  return name === 'General_Category' || name == 'gc';
+}
+
+function isScriptCategoryName(name) {
+  return name === 'Script' || name === 'Script_Extensions' || name === 'sc' || name === 'scx';
+}
+
+function isGeneralCategoryValue(value) {
+  return GENERAL_CATEGORY_VALUE_TO_ALIASES.hasOwnProperty(value) || GENERAL_CATEGORY_VALUE_ALIASES_TO_VALUES.hasOwnProperty(value);
+}
+
+function isScriptCategoryValue(value) {
+  return SCRIPT_VALUE_TO_ALIASES.hasOwnProperty(value) || SCRIPT_VALUE_ALIASES_TO_VALUE.hasOwnProperty(value);
+}
+
+function isBinaryPropertyName(name) {
+  return BINARY_PROP_NAMES_TO_ALIASES.hasOwnProperty(name) || BINARY_ALIASES_TO_PROP_NAMES.hasOwnProperty(name);
+}
+
+function getCanonicalName(name) {
+  if (NON_BINARY_ALIASES_TO_PROP_NAMES.hasOwnProperty(name)) {
+    return NON_BINARY_ALIASES_TO_PROP_NAMES[name];
+  }
+
+  if (BINARY_ALIASES_TO_PROP_NAMES.hasOwnProperty(name)) {
+    return BINARY_ALIASES_TO_PROP_NAMES[name];
+  }
+
+  return null;
+}
+
+function getCanonicalValue(value) {
+  if (GENERAL_CATEGORY_VALUE_ALIASES_TO_VALUES.hasOwnProperty(value)) {
+    return GENERAL_CATEGORY_VALUE_ALIASES_TO_VALUES[value];
+  }
+
+  if (SCRIPT_VALUE_ALIASES_TO_VALUE.hasOwnProperty(value)) {
+    return SCRIPT_VALUE_ALIASES_TO_VALUE[value];
+  }
+
+  if (BINARY_ALIASES_TO_PROP_NAMES.hasOwnProperty(value)) {
+    return BINARY_ALIASES_TO_PROP_NAMES[value];
+  }
+
+  return null;
+}
+
+module.exports = {
+  isAlias: isAlias,
+  isValidName: isValidName,
+  isValidValue: isValidValue,
+  isGeneralCategoryValue: isGeneralCategoryValue,
+  isScriptCategoryValue: isScriptCategoryValue,
+  isBinaryPropertyName: isBinaryPropertyName,
+  getCanonicalName: getCanonicalName,
+  getCanonicalValue: getCanonicalValue,
+
+  NON_BINARY_PROP_NAMES_TO_ALIASES: NON_BINARY_PROP_NAMES_TO_ALIASES,
+  NON_BINARY_ALIASES_TO_PROP_NAMES: NON_BINARY_ALIASES_TO_PROP_NAMES,
+
+  BINARY_PROP_NAMES_TO_ALIASES: BINARY_PROP_NAMES_TO_ALIASES,
+  BINARY_ALIASES_TO_PROP_NAMES: BINARY_ALIASES_TO_PROP_NAMES,
+
+  GENERAL_CATEGORY_VALUE_TO_ALIASES: GENERAL_CATEGORY_VALUE_TO_ALIASES,
+  GENERAL_CATEGORY_VALUE_ALIASES_TO_VALUES: GENERAL_CATEGORY_VALUE_ALIASES_TO_VALUES,
+
+  SCRIPT_VALUE_TO_ALIASES: SCRIPT_VALUE_TO_ALIASES,
+  SCRIPT_VALUE_ALIASES_TO_VALUE: SCRIPT_VALUE_ALIASES_TO_VALUE
+};

node_modules/regexp-tree/dist/regexp-tree.js

@@ -0,0 +1,178 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+var compatTranspiler = require('./compat-transpiler');
+var generator = require('./generator');
+var optimizer = require('./optimizer');
+var parser = require('./parser');
+var _transform = require('./transform');
+var _traverse = require('./traverse');
+var fa = require('./interpreter/finite-automaton');
+
+var _require = require('./compat-transpiler/runtime'),
+    RegExpTree = _require.RegExpTree;
+
+/**
+ * An API object for RegExp processing (parsing/transform/generation).
+ */
+
+
+var regexpTree = {
+  /**
+   * Parser module exposed.
+   */
+  parser: parser,
+
+  /**
+   * Expose finite-automaton module.
+   */
+  fa: fa,
+
+  /**
+   * `TransformResult` exposed.
+   */
+  TransformResult: _transform.TransformResult,
+
+  /**
+   * Parses a regexp string, producing an AST.
+   *
+   * @param string regexp
+   *
+   *   a regular expression in different formats: string, AST, RegExp.
+   *
+   * @param Object options
+   *
+   *   parsing options for this parse call. Default are:
+   *
+   *     - captureLocations: boolean
+   *     - any other custom options
+   *
+   * @return Object AST
+   */
+  parse: function parse(regexp, options) {
+    return parser.parse('' + regexp, options);
+  },
+
+
+  /**
+   * Traverses a RegExp AST.
+   *
+   * @param Object ast
+   * @param Object | Array<Object> handlers
+   *
+   * Each `handler` is an object containing handler function for needed
+   * node types. Example:
+   *
+   *   regexpTree.traverse(ast, {
+   *     onChar(node) {
+   *       ...
+   *     },
+   *   });
+  *
+  * The value for a node type may also be an object with functions pre and post.
+  * This enables more context-aware analyses, e.g. measuring star height.
+   */
+  traverse: function traverse(ast, handlers, options) {
+    return _traverse.traverse(ast, handlers, options);
+  },
+
+
+  /**
+   * Transforms a regular expression.
+   *
+   * A regexp can be passed in different formats (string, regexp or AST),
+   * applying a set of transformations. It is a convenient wrapper
+   * on top of "parse-traverse-generate" tool chain.
+   *
+   * @param string | AST | RegExp regexp - a regular expression;
+   * @param Object | Array<Object> handlers - a list of handlers.
+   *
+   * @return TransformResult - a transformation result.
+   */
+  transform: function transform(regexp, handlers) {
+    return _transform.transform(regexp, handlers);
+  },
+
+
+  /**
+   * Generates a RegExp string from an AST.
+   *
+   * @param Object ast
+   *
+   * Invariant:
+   *
+   *   regexpTree.generate(regexpTree.parse('/[a-z]+/i')); // '/[a-z]+/i'
+   */
+  generate: function generate(ast) {
+    return generator.generate(ast);
+  },
+
+
+  /**
+   * Creates a RegExp object from a regexp string.
+   *
+   * @param string regexp
+   */
+  toRegExp: function toRegExp(regexp) {
+    var compat = this.compatTranspile(regexp);
+    return new RegExp(compat.getSource(), compat.getFlags());
+  },
+
+
+  /**
+   * Optimizes a regular expression by replacing some
+   * sub-expressions with their idiomatic patterns.
+   *
+   * @param string regexp
+   *
+   * @return TransformResult object
+   */
+  optimize: function optimize(regexp, whitelist) {
+    return optimizer.optimize(regexp, whitelist);
+  },
+
+
+  /**
+   * Translates a regular expression in new syntax or in new format
+   * into equivalent expressions in old syntax.
+   *
+   * @param string regexp
+   *
+   * @return TransformResult object
+   */
+  compatTranspile: function compatTranspile(regexp, whitelist) {
+    return compatTranspiler.transform(regexp, whitelist);
+  },
+
+
+  /**
+   * Executes a regular expression on a string.
+   *
+   * @param RegExp|string re - a regular expression.
+   * @param string string - a testing string.
+   */
+  exec: function exec(re, string) {
+    if (typeof re === 'string') {
+      var compat = this.compatTranspile(re);
+      var extra = compat.getExtra();
+
+      if (extra.namedCapturingGroups) {
+        re = new RegExpTree(compat.toRegExp(), {
+          flags: compat.getFlags(),
+          source: compat.getSource(),
+          groups: extra.namedCapturingGroups
+        });
+      } else {
+        re = compat.toRegExp();
+      }
+    }
+
+    return re.exec(string);
+  }
+};
+
+module.exports = regexpTree;

node_modules/regexp-tree/dist/transform/index.js

@@ -0,0 +1,138 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();
+
+function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
+
+var generator = require('../generator');
+var parser = require('../parser');
+var traverse = require('../traverse');
+
+/**
+ * Transform result.
+ */
+
+var TransformResult = function () {
+  /**
+   * Initializes a transform result for an AST.
+   *
+   * @param Object ast - an AST node
+   * @param mixed extra - any extra data a transform may return
+   */
+  function TransformResult(ast) {
+    var extra = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : null;
+
+    _classCallCheck(this, TransformResult);
+
+    this._ast = ast;
+    this._source = null;
+    this._string = null;
+    this._regexp = null;
+    this._extra = extra;
+  }
+
+  _createClass(TransformResult, [{
+    key: 'getAST',
+    value: function getAST() {
+      return this._ast;
+    }
+  }, {
+    key: 'setExtra',
+    value: function setExtra(extra) {
+      this._extra = extra;
+    }
+  }, {
+    key: 'getExtra',
+    value: function getExtra() {
+      return this._extra;
+    }
+  }, {
+    key: 'toRegExp',
+    value: function toRegExp() {
+      if (!this._regexp) {
+        this._regexp = new RegExp(this.getSource(), this._ast.flags);
+      }
+      return this._regexp;
+    }
+  }, {
+    key: 'getSource',
+    value: function getSource() {
+      if (!this._source) {
+        this._source = generator.generate(this._ast.body);
+      }
+      return this._source;
+    }
+  }, {
+    key: 'getFlags',
+    value: function getFlags() {
+      return this._ast.flags;
+    }
+  }, {
+    key: 'toString',
+    value: function toString() {
+      if (!this._string) {
+        this._string = generator.generate(this._ast);
+      }
+      return this._string;
+    }
+  }]);
+
+  return TransformResult;
+}();
+
+module.exports = {
+  /**
+   * Expose `TransformResult`.
+   */
+  TransformResult: TransformResult,
+
+  /**
+   * Transforms a regular expression applying a set of
+   * transformation handlers.
+   *
+   * @param string | AST | RegExp:
+   *
+   *   a regular expression in different representations: a string,
+   *   a RegExp object, or an AST.
+   *
+   * @param Object | Array<Object>:
+   *
+   *   a handler (or a list of handlers) from `traverse` API.
+   *
+   * @return TransformResult instance.
+   *
+   * Example:
+   *
+   *   transform(/[a-z]/i, {
+   *     onChar(path) {
+   *       const {node} = path;
+   *
+   *       if (...) {
+   *         path.remove();
+   *       }
+   *     }
+   *   });
+   */
+  transform: function transform(regexp, handlers) {
+    var ast = regexp;
+
+    if (regexp instanceof RegExp) {
+      regexp = '' + regexp;
+    }
+
+    if (typeof regexp === 'string') {
+      ast = parser.parse(regexp, {
+        captureLocations: true
+      });
+    }
+
+    traverse.traverse(ast, handlers);
+
+    return new TransformResult(ast);
+  }
+};

node_modules/regexp-tree/dist/transform/utils.js

@@ -0,0 +1,88 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+/**
+ * Flattens a nested disjunction node to a list.
+ *
+ * /a|b|c|d/
+ *
+ * {{{a, b}, c}, d} -> [a, b, c, d]
+ */
+
+function _toConsumableArray(arr) { if (Array.isArray(arr)) { for (var i = 0, arr2 = Array(arr.length); i < arr.length; i++) { arr2[i] = arr[i]; } return arr2; } else { return Array.from(arr); } }
+
+function disjunctionToList(node) {
+  if (node.type !== 'Disjunction') {
+    throw new TypeError('Expected "Disjunction" node, got "' + node.type + '"');
+  }
+
+  var list = [];
+
+  if (node.left && node.left.type === 'Disjunction') {
+    list.push.apply(list, _toConsumableArray(disjunctionToList(node.left)).concat([node.right]));
+  } else {
+    list.push(node.left, node.right);
+  }
+
+  return list;
+}
+
+/**
+ * Builds a nested disjunction node from a list.
+ *
+ * /a|b|c|d/
+ *
+ * [a, b, c, d] -> {{{a, b}, c}, d}
+ */
+function listToDisjunction(list) {
+  return list.reduce(function (left, right) {
+    return {
+      type: 'Disjunction',
+      left: left,
+      right: right
+    };
+  });
+}
+
+/**
+ * Increases a quantifier by one.
+ * Does not change greediness.
+ * * -> +
+ * + -> {2,}
+ * ? -> {1,2}
+ * {2} -> {3}
+ * {2,} -> {3,}
+ * {2,3} -> {3,4}
+ */
+function increaseQuantifierByOne(quantifier) {
+  if (quantifier.kind === '*') {
+
+    quantifier.kind = '+';
+  } else if (quantifier.kind === '+') {
+
+    quantifier.kind = 'Range';
+    quantifier.from = 2;
+    delete quantifier.to;
+  } else if (quantifier.kind === '?') {
+
+    quantifier.kind = 'Range';
+    quantifier.from = 1;
+    quantifier.to = 2;
+  } else if (quantifier.kind === 'Range') {
+
+    quantifier.from += 1;
+    if (quantifier.to) {
+      quantifier.to += 1;
+    }
+  }
+}
+
+module.exports = {
+  disjunctionToList: disjunctionToList,
+  listToDisjunction: listToDisjunction,
+  increaseQuantifierByOne: increaseQuantifierByOne
+};

node_modules/regexp-tree/dist/traverse/index.js

@@ -0,0 +1,313 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+var NodePath = require('./node-path');
+
+/**
+ * Does an actual AST traversal, using visitor pattern,
+ * and calling set of callbacks.
+ *
+ * Based on https://github.com/olov/ast-traverse
+ *
+ * Expects AST in Mozilla Parser API: nodes which are supposed to be
+ * handled should have `type` property.
+ *
+ * @param Object root - a root node to start traversal from.
+ *
+ * @param Object options - an object with set of callbacks:
+ *
+ *   - `pre(node, parent, prop, index)` - a hook called on node enter
+ *   - `post`(node, parent, prop, index) - a hook called on node exit
+ *   - `skipProperty(prop)` - a predicated whether a property should be skipped
+ */
+function astTraverse(root) {
+  var options = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {};
+
+  var pre = options.pre;
+  var post = options.post;
+  var skipProperty = options.skipProperty;
+
+  function visit(node, parent, prop, idx) {
+    if (!node || typeof node.type !== 'string') {
+      return;
+    }
+
+    var res = undefined;
+    if (pre) {
+      res = pre(node, parent, prop, idx);
+    }
+
+    if (res !== false) {
+
+      // A node can be replaced during traversal, so we have to
+      // recalculate it from the parent, to avoid traversing "dead" nodes.
+      if (parent && parent[prop]) {
+        if (!isNaN(idx)) {
+          node = parent[prop][idx];
+        } else {
+          node = parent[prop];
+        }
+      }
+
+      for (var _prop in node) {
+        if (node.hasOwnProperty(_prop)) {
+          if (skipProperty ? skipProperty(_prop, node) : _prop[0] === '$') {
+            continue;
+          }
+
+          var child = node[_prop];
+
+          // Collection node.
+          //
+          // NOTE: a node (or several nodes) can be removed or inserted
+          // during traversal.
+          //
+          // Current traversing index is stored on top of the
+          // `NodePath.traversingIndexStack`. The stack is used to support
+          // recursive nature of the traversal.
+          //
+          // In this case `NodePath.traversingIndex` (which we use here) is
+          // updated in the NodePath remove/insert methods.
+          //
+          if (Array.isArray(child)) {
+            var index = 0;
+            NodePath.traversingIndexStack.push(index);
+            while (index < child.length) {
+              visit(child[index], node, _prop, index);
+              index = NodePath.updateTraversingIndex(+1);
+            }
+            NodePath.traversingIndexStack.pop();
+          }
+
+          // Simple node.
+          else {
+              visit(child, node, _prop);
+            }
+        }
+      }
+    }
+
+    if (post) {
+      post(node, parent, prop, idx);
+    }
+  }
+
+  visit(root, null);
+}
+
+module.exports = {
+  /**
+   * Traverses an AST.
+   *
+   * @param Object ast - an AST node
+   *
+   * @param Object | Array<Object> handlers:
+   *
+   *   an object (or an array of objects)
+   *
+   *   Each such object contains a handler function per node.
+   *   In case of an array of handlers, they are applied in order.
+   *   A handler may return a transformed node (or a different type).
+   *
+   *   The per-node function may instead be an object with functions pre and post.
+   *   pre is called before visiting the node, post after.
+   *   If a handler is a function, it is treated as the pre function, with an empty post.
+   *
+   * @param Object options:
+   *
+   *   a config object, specifying traversal options:
+   *
+   *   `asNodes`: boolean - whether handlers should receives raw AST nodes
+   *   (false by default), instead of a `NodePath` wrapper. Note, by default
+   *   `NodePath` wrapper provides a set of convenient method to manipulate
+   *   a traversing AST, and also has access to all parents list. A raw
+   *   nodes traversal should be used in rare cases, when no `NodePath`
+   *   features are needed.
+   *
+   * Special hooks:
+   *
+   *   - `shouldRun(ast)` - a predicate determining whether the handler
+   *                        should be applied.
+   *
+   * NOTE: Multiple handlers are used as an optimization of applying all of
+   * them in one AST traversal pass.
+   */
+  traverse: function traverse(ast, handlers) {
+    var options = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : { asNodes: false };
+
+
+    if (!Array.isArray(handlers)) {
+      handlers = [handlers];
+    }
+
+    // Filter out handlers by result of `shouldRun`, if the method is present.
+    handlers = handlers.filter(function (handler) {
+      if (typeof handler.shouldRun !== 'function') {
+        return true;
+      }
+      return handler.shouldRun(ast);
+    });
+
+    NodePath.initRegistry();
+
+    // Allow handlers to initializer themselves.
+    handlers.forEach(function (handler) {
+      if (typeof handler.init === 'function') {
+        handler.init(ast);
+      }
+    });
+
+    function getPathFor(node, parent, prop, index) {
+      var parentPath = NodePath.getForNode(parent);
+      var nodePath = NodePath.getForNode(node, parentPath, prop, index);
+
+      return nodePath;
+    }
+
+    // Handle actual nodes.
+    astTraverse(ast, {
+      /**
+       * Handler on node enter.
+       */
+      pre: function pre(node, parent, prop, index) {
+        var nodePath = void 0;
+        if (!options.asNodes) {
+          nodePath = getPathFor(node, parent, prop, index);
+        }
+
+        var _iteratorNormalCompletion = true;
+        var _didIteratorError = false;
+        var _iteratorError = undefined;
+
+        try {
+          for (var _iterator = handlers[Symbol.iterator](), _step; !(_iteratorNormalCompletion = (_step = _iterator.next()).done); _iteratorNormalCompletion = true) {
+            var handler = _step.value;
+
+            // "Catch-all" `*` handler.
+            if (typeof handler['*'] === 'function') {
+              if (nodePath) {
+                // A path/node can be removed by some previous handler.
+                if (!nodePath.isRemoved()) {
+                  var handlerResult = handler['*'](nodePath);
+                  // Explicitly stop traversal.
+                  if (handlerResult === false) {
+                    return false;
+                  }
+                }
+              } else {
+                handler['*'](node, parent, prop, index);
+              }
+            }
+
+            // Per-node handler.
+            var handlerFuncPre = void 0;
+            if (typeof handler[node.type] === 'function') {
+              handlerFuncPre = handler[node.type];
+            } else if (typeof handler[node.type] === 'object' && typeof handler[node.type].pre === 'function') {
+              handlerFuncPre = handler[node.type].pre;
+            }
+
+            if (handlerFuncPre) {
+              if (nodePath) {
+                // A path/node can be removed by some previous handler.
+                if (!nodePath.isRemoved()) {
+                  var _handlerResult = handlerFuncPre.call(handler, nodePath);
+                  // Explicitly stop traversal.
+                  if (_handlerResult === false) {
+                    return false;
+                  }
+                }
+              } else {
+                handlerFuncPre.call(handler, node, parent, prop, index);
+              }
+            }
+          } // Loop over handlers
+        } catch (err) {
+          _didIteratorError = true;
+          _iteratorError = err;
+        } finally {
+          try {
+            if (!_iteratorNormalCompletion && _iterator.return) {
+              _iterator.return();
+            }
+          } finally {
+            if (_didIteratorError) {
+              throw _iteratorError;
+            }
+          }
+        }
+      },
+      // pre func
+
+      /**
+       * Handler on node exit.
+       */
+      post: function post(node, parent, prop, index) {
+        if (!node) {
+          return;
+        }
+
+        var nodePath = void 0;
+        if (!options.asNodes) {
+          nodePath = getPathFor(node, parent, prop, index);
+        }
+
+        var _iteratorNormalCompletion2 = true;
+        var _didIteratorError2 = false;
+        var _iteratorError2 = undefined;
+
+        try {
+          for (var _iterator2 = handlers[Symbol.iterator](), _step2; !(_iteratorNormalCompletion2 = (_step2 = _iterator2.next()).done); _iteratorNormalCompletion2 = true) {
+            var handler = _step2.value;
+
+            // Per-node handler.
+            var handlerFuncPost = void 0;
+            if (typeof handler[node.type] === 'object' && typeof handler[node.type].post === 'function') {
+              handlerFuncPost = handler[node.type].post;
+            }
+
+            if (handlerFuncPost) {
+              if (nodePath) {
+                // A path/node can be removed by some previous handler.
+                if (!nodePath.isRemoved()) {
+                  var handlerResult = handlerFuncPost.call(handler, nodePath);
+                  // Explicitly stop traversal.
+                  if (handlerResult === false) {
+                    return false;
+                  }
+                }
+              } else {
+                handlerFuncPost.call(handler, node, parent, prop, index);
+              }
+            }
+          } // Loop over handlers
+        } catch (err) {
+          _didIteratorError2 = true;
+          _iteratorError2 = err;
+        } finally {
+          try {
+            if (!_iteratorNormalCompletion2 && _iterator2.return) {
+              _iterator2.return();
+            }
+          } finally {
+            if (_didIteratorError2) {
+              throw _iteratorError2;
+            }
+          }
+        }
+      },
+      // post func
+
+      /**
+       * Skip locations by default.
+       */
+      skipProperty: function skipProperty(prop) {
+        return prop === 'loc';
+      }
+    });
+  }
+};

node_modules/regexp-tree/dist/traverse/node-path.js

@@ -0,0 +1,426 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();
+
+function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
+
+var DEFAULT_COLLECTION_PROP = 'expressions';
+var DEFAULT_SINGLE_PROP = 'expression';
+
+/**
+ * NodePath class encapsulates a traversing node,
+ * its parent node, property name in the parent node, and
+ * an index (in case if a node is part of a collection).
+ * It also provides set of methods for AST manipulation.
+ */
+
+var NodePath = function () {
+  /**
+   * NodePath constructor.
+   *
+   * @param Object node - an AST node
+   * @param NodePath parentPath - a nullable parent path
+   * @param string property - property name of the node in the parent
+   * @param number index - index of the node in a collection.
+   */
+  function NodePath(node) {
+    var parentPath = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : null;
+    var property = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : null;
+    var index = arguments.length > 3 && arguments[3] !== undefined ? arguments[3] : null;
+
+    _classCallCheck(this, NodePath);
+
+    this.node = node;
+    this.parentPath = parentPath;
+    this.parent = parentPath ? parentPath.node : null;
+    this.property = property;
+    this.index = index;
+  }
+
+  _createClass(NodePath, [{
+    key: '_enforceProp',
+    value: function _enforceProp(property) {
+      if (!this.node.hasOwnProperty(property)) {
+        throw new Error('Node of type ' + this.node.type + ' doesn\'t have "' + property + '" collection.');
+      }
+    }
+
+    /**
+     * Sets a node into a children collection or the single child.
+     * By default child nodes are supposed to be under `expressions` property.
+     * An explicit property can be passed.
+     *
+     * @param Object node - a node to set into a collection or as single child
+     * @param number index - index at which to set
+     * @param string property - name of the collection or single property
+     */
+
+  }, {
+    key: 'setChild',
+    value: function setChild(node) {
+      var index = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : null;
+      var property = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : null;
+
+
+      var childPath = void 0;
+      if (index != null) {
+        if (!property) {
+          property = DEFAULT_COLLECTION_PROP;
+        }
+        this._enforceProp(property);
+        this.node[property][index] = node;
+        childPath = NodePath.getForNode(node, this, property, index);
+      } else {
+        if (!property) {
+          property = DEFAULT_SINGLE_PROP;
+        }
+        this._enforceProp(property);
+        this.node[property] = node;
+        childPath = NodePath.getForNode(node, this, property, null);
+      }
+      return childPath;
+    }
+
+    /**
+     * Appends a node to a children collection.
+     * By default child nodes are supposed to be under `expressions` property.
+     * An explicit property can be passed.
+     *
+     * @param Object node - a node to set into a collection or as single child
+     * @param string property - name of the collection or single property
+     */
+
+  }, {
+    key: 'appendChild',
+    value: function appendChild(node) {
+      var property = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : null;
+
+
+      if (!property) {
+        property = DEFAULT_COLLECTION_PROP;
+      }
+      this._enforceProp(property);
+      var end = this.node[property].length;
+      return this.setChild(node, end, property);
+    }
+
+    /**
+     * Inserts a node into a collection.
+     * By default child nodes are supposed to be under `expressions` property.
+     * An explicit property can be passed.
+     *
+     * @param Object node - a node to insert into a collection
+     * @param number index - index at which to insert
+     * @param string property - name of the collection property
+     */
+
+  }, {
+    key: 'insertChildAt',
+    value: function insertChildAt(node, index) {
+      var property = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : DEFAULT_COLLECTION_PROP;
+
+      this._enforceProp(property);
+
+      this.node[property].splice(index, 0, node);
+
+      // If we inserted a node before the traversing index,
+      // we should increase the later.
+      if (index <= NodePath.getTraversingIndex()) {
+        NodePath.updateTraversingIndex(+1);
+      }
+
+      this._rebuildIndex(this.node, property);
+    }
+
+    /**
+     * Removes a node.
+     */
+
+  }, {
+    key: 'remove',
+    value: function remove() {
+      if (this.isRemoved()) {
+        return;
+      }
+      NodePath.registry.delete(this.node);
+
+      this.node = null;
+
+      if (!this.parent) {
+        return;
+      }
+
+      // A node is in a collection.
+      if (this.index !== null) {
+        this.parent[this.property].splice(this.index, 1);
+
+        // If we remove a node before the traversing index,
+        // we should increase the later.
+        if (this.index <= NodePath.getTraversingIndex()) {
+          NodePath.updateTraversingIndex(-1);
+        }
+
+        // Rebuild index.
+        this._rebuildIndex(this.parent, this.property);
+
+        this.index = null;
+        this.property = null;
+
+        return;
+      }
+
+      // A simple node.
+      delete this.parent[this.property];
+      this.property = null;
+    }
+
+    /**
+     * Rebuilds child nodes index (used on remove/insert).
+     */
+
+  }, {
+    key: '_rebuildIndex',
+    value: function _rebuildIndex(parent, property) {
+      var parentPath = NodePath.getForNode(parent);
+
+      for (var i = 0; i < parent[property].length; i++) {
+        var path = NodePath.getForNode(parent[property][i], parentPath, property, i);
+        path.index = i;
+      }
+    }
+
+    /**
+     * Whether the path was removed.
+     */
+
+  }, {
+    key: 'isRemoved',
+    value: function isRemoved() {
+      return this.node === null;
+    }
+
+    /**
+     * Replaces a node with the passed one.
+     */
+
+  }, {
+    key: 'replace',
+    value: function replace(newNode) {
+      NodePath.registry.delete(this.node);
+
+      this.node = newNode;
+
+      if (!this.parent) {
+        return null;
+      }
+
+      // A node is in a collection.
+      if (this.index !== null) {
+        this.parent[this.property][this.index] = newNode;
+      }
+
+      // A simple node.
+      else {
+          this.parent[this.property] = newNode;
+        }
+
+      // Rebuild the node path for the new node.
+      return NodePath.getForNode(newNode, this.parentPath, this.property, this.index);
+    }
+
+    /**
+     * Updates a node inline.
+     */
+
+  }, {
+    key: 'update',
+    value: function update(nodeProps) {
+      Object.assign(this.node, nodeProps);
+    }
+
+    /**
+     * Returns parent.
+     */
+
+  }, {
+    key: 'getParent',
+    value: function getParent() {
+      return this.parentPath;
+    }
+
+    /**
+     * Returns nth child.
+     */
+
+  }, {
+    key: 'getChild',
+    value: function getChild() {
+      var n = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : 0;
+
+      if (this.node.expressions) {
+        return NodePath.getForNode(this.node.expressions[n], this, DEFAULT_COLLECTION_PROP, n);
+      } else if (this.node.expression && n == 0) {
+        return NodePath.getForNode(this.node.expression, this, DEFAULT_SINGLE_PROP);
+      }
+      return null;
+    }
+
+    /**
+     * Whether a path node is syntactically equal to the passed one.
+     *
+     * NOTE: we don't rely on `source` property from the `loc` data
+     * (which would be the fastest comparison), since it might be unsync
+     * after several modifications. We use here simple `JSON.stringify`
+     * excluding the `loc` data.
+     *
+     * @param NodePath other - path to compare to.
+     * @return boolean
+     */
+
+  }, {
+    key: 'hasEqualSource',
+    value: function hasEqualSource(path) {
+      return JSON.stringify(this.node, jsonSkipLoc) === JSON.stringify(path.node, jsonSkipLoc);
+    }
+
+    /**
+     * JSON-encodes a node skipping location.
+     */
+
+  }, {
+    key: 'jsonEncode',
+    value: function jsonEncode() {
+      var _ref = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : {},
+          format = _ref.format,
+          useLoc = _ref.useLoc;
+
+      return JSON.stringify(this.node, useLoc ? null : jsonSkipLoc, format);
+    }
+
+    /**
+     * Returns previous sibling.
+     */
+
+  }, {
+    key: 'getPreviousSibling',
+    value: function getPreviousSibling() {
+      if (!this.parent || this.index == null) {
+        return null;
+      }
+      return NodePath.getForNode(this.parent[this.property][this.index - 1], NodePath.getForNode(this.parent), this.property, this.index - 1);
+    }
+
+    /**
+     * Returns next sibling.
+     */
+
+  }, {
+    key: 'getNextSibling',
+    value: function getNextSibling() {
+      if (!this.parent || this.index == null) {
+        return null;
+      }
+      return NodePath.getForNode(this.parent[this.property][this.index + 1], NodePath.getForNode(this.parent), this.property, this.index + 1);
+    }
+
+    /**
+     * Returns a NodePath instance for a node.
+     *
+     * The same NodePath can be reused in several places, e.g.
+     * a parent node passed for all its children.
+     */
+
+  }], [{
+    key: 'getForNode',
+    value: function getForNode(node) {
+      var parentPath = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : null;
+      var prop = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : null;
+      var index = arguments.length > 3 && arguments[3] !== undefined ? arguments[3] : -1;
+
+      if (!node) {
+        return null;
+      }
+
+      if (!NodePath.registry.has(node)) {
+        NodePath.registry.set(node, new NodePath(node, parentPath, prop, index == -1 ? null : index));
+      }
+
+      var path = NodePath.registry.get(node);
+
+      if (parentPath !== null) {
+        path.parentPath = parentPath;
+        path.parent = path.parentPath.node;
+      }
+
+      if (prop !== null) {
+        path.property = prop;
+      }
+
+      if (index >= 0) {
+        path.index = index;
+      }
+
+      return path;
+    }
+
+    /**
+     * Initializes the NodePath registry. The registry is a map from
+     * a node to its NodePath instance.
+     */
+
+  }, {
+    key: 'initRegistry',
+    value: function initRegistry() {
+      if (!NodePath.registry) {
+        NodePath.registry = new Map();
+      }
+      NodePath.registry.clear();
+    }
+
+    /**
+     * Updates index of a currently traversing collection.
+     */
+
+  }, {
+    key: 'updateTraversingIndex',
+    value: function updateTraversingIndex(dx) {
+      return NodePath.traversingIndexStack[NodePath.traversingIndexStack.length - 1] += dx;
+    }
+
+    /**
+     * Returns current traversing index.
+     */
+
+  }, {
+    key: 'getTraversingIndex',
+    value: function getTraversingIndex() {
+      return NodePath.traversingIndexStack[NodePath.traversingIndexStack.length - 1];
+    }
+  }]);
+
+  return NodePath;
+}();
+
+NodePath.initRegistry();
+
+/**
+ * Index of a currently traversing collection is stored on top of the
+ * `NodePath.traversingIndexStack`. Remove/insert methods can adjust
+ * this index.
+ */
+NodePath.traversingIndexStack = [];
+
+// Helper function used to skip `loc` in JSON operations.
+function jsonSkipLoc(prop, value) {
+  if (prop === 'loc') {
+    return undefined;
+  }
+  return value;
+}
+
+module.exports = NodePath;

node_modules/regexp-tree/dist/utils/clone.js

@@ -0,0 +1,29 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+/**
+ * Performs a deep copy of an simple object.
+ * Only handles scalar values, arrays and objects.
+ *
+ * @param obj Object
+ */
+
+module.exports = function clone(obj) {
+  if (obj === null || typeof obj !== 'object') {
+    return obj;
+  }
+  var res = void 0;
+  if (Array.isArray(obj)) {
+    res = [];
+  } else {
+    res = {};
+  }
+  for (var i in obj) {
+    res[i] = clone(obj[i]);
+  }
+  return res;
+};

node_modules/regexp-tree/index.d.ts

@@ -0,0 +1,294 @@
+declare module 'regexp-tree/ast' {
+  export interface AstClassMap {
+    'RegExp': AstRegExp;
+    'Disjunction': Disjunction;
+    'Alternative': Alternative;
+    'Assertion': Assertion;
+    'Char': Char;
+    'CharacterClass': CharacterClass;
+    'ClassRange': ClassRange;
+    'Backreference': Backreference;
+    'Group': Group;
+    'Repetition': Repetition;
+    'Quantifier': Quantifier;
+  }
+
+  export type AstClass = keyof AstClassMap;
+  export type AstNode = AstClassMap[AstClass];
+
+  export interface Base<T extends AstClass> {
+    type: T;
+    loc?: {
+      source: string;
+      start: number;
+      end: number;
+    };
+  }
+
+  export interface SimpleChar extends Base<'Char'> {
+    value: string;
+    kind: 'simple';
+    escaped?: true;
+  }
+
+  export interface SpecialChar extends Base<'Char'> {
+    value: string;
+    kind: 'meta' | 'control' | 'hex' | 'decimal' | 'oct' | 'unicode';
+  }
+
+  export type Char =
+    | SimpleChar
+    | SpecialChar;
+
+  export interface ClassRange extends Base<'ClassRange'> {
+    from: Char;
+    to: Char;
+  }
+
+  export interface CharacterClass extends Base<'CharacterClass'> {
+    negative?: true;
+    expressions: (Char | ClassRange)[];
+  }
+
+  export interface Alternative extends Base<'Alternative'> {
+    expressions: Expression[];
+  }
+
+  export interface Disjunction extends Base<'Disjunction'> {
+    expressions: (Expression | null)[];
+  }
+
+  export interface CapturingGroup extends Base<'Group'> {
+    capturing: true;
+    number: number;
+    name?: string;
+    nameRaw?: string;
+    expression: Expression | null;
+  }
+
+  export interface NoncapturingGroup extends Base<'Group'> {
+    capturing: false;
+    expression: Expression | null;
+  }
+
+  export type Group =
+    | CapturingGroup
+    | NoncapturingGroup;
+
+  export interface NumericBackreference extends Base<'Backreference'> {
+    kind: 'number';
+    number: number;
+    reference: number;
+  }
+
+  export interface NamedBackreference extends Base<'Backreference'> {
+    kind: 'name';
+    number: number;
+    reference: string;
+    referenceRaw: string;
+  }
+
+  export type Backreference =
+    | NumericBackreference
+    | NamedBackreference;
+
+  export interface Repetition extends Base<'Repetition'> {
+    expression: Expression;
+    quantifier: Quantifier;
+  }
+
+  export interface SimpleQuantifier extends Base<'Quantifier'> {
+    kind: '+' | '*' | '?';
+    greedy: boolean;
+  }
+
+  export interface RangeQuantifier extends Base<'Quantifier'> {
+    kind: 'Range';
+    from: number;
+    to?: number;
+    greedy: boolean;
+  }
+
+  export type Quantifier =
+    | SimpleQuantifier
+    | RangeQuantifier;
+
+  export interface SimpleAssertion extends Base<'Assertion'> {
+    kind: '^' | '$' | '\\b' | '\\B';
+  }
+
+  export interface LookaroundAssertion extends Base<'Assertion'> {
+    kind: 'Lookahead' | 'Lookbehind';
+    negative?: true;
+    assertion: Expression | null;
+  }
+
+  export type Assertion =
+    | SimpleAssertion
+    | LookaroundAssertion;
+
+  export type Expression =
+    | Char
+    | CharacterClass
+    | Alternative
+    | Disjunction
+    | Group
+    | Backreference
+    | Repetition
+    | Assertion;
+
+  export interface AstRegExp extends Base<'RegExp'> {
+    body: Expression | null;
+    flags: string;
+  }
+}
+
+declare module 'regexp-tree' {
+  import {
+    AstRegExp,
+    AstNode,
+    AstClass,
+    AstClassMap
+  } from 'regexp-tree/ast'
+
+  export interface ParserOptions {
+    captureLocations?: boolean;
+  }
+
+  /**
+   * Parses a regexp string, producing an AST.
+   *
+   * @param regexp a regular expression in different formats: string, AST, RegExp.
+   * @param options parsing options for this parse call.
+   */
+  export function parse(regexp: string | RegExp, options?: ParserOptions): AstRegExp;
+
+  /**
+   * Generates a RegExp string from an AST.
+   */
+  export function generate(ast: AstNode | null | undefined): string;
+
+  /**
+   * Creates a RegExp object from a regexp string.
+   */
+  export function toRegExp(regexp: string): RegExp;
+
+  export interface NodePath<T extends AstNode = AstNode> {
+    node: T;
+    parent: AstNode | null;
+    parentPath: NodePath | null;
+    property: string | null;
+    index: number | null;
+    getParent(): NodePath | null;
+    getChild(n?: number): NodePath | null;
+    getPreviousSibling(): NodePath | null;
+    getNextSibling(): NodePath | null;
+    setChild<T extends AstNode>(node: T | null, index?: number | null, property?: string | null): NodePath<T> | null;
+    appendChild<T extends AstNode>(node: T | null, property?: string | null): NodePath<T> | null;
+    insertChildAt<T extends AstNode>(node: T | null, index: number, property?: string | null): void;
+    replace<T extends AstNode>(node: T): NodePath<T> | null;
+    update(nodeProps: Partial<T>): void;
+    remove(): void;
+    isRemoved(): boolean;
+    hasEqualSource(path: NodePath<T>): boolean;
+    jsonEncode(options?: { format?: string | number, useLoc?: boolean }): string;
+  }
+
+  export type NodeTraversalCallback<T extends AstNode = AstNode> = (node: T, parent: NodePath | null, property?: string, index?: number) => void | boolean;
+
+  export interface NodeTraversalCallbacks<T extends AstNode = AstNode> {
+    pre?: NodeTraversalCallback<T>;
+    post?: NodeTraversalCallback<T>;
+  }
+
+  export type SpecificNodeTraversalHandlers = {
+    [P in AstClass]?: NodeTraversalCallback<AstClassMap[P]> | NodeTraversalCallbacks<AstClassMap[P]>;
+  };
+
+  export interface NodeTraversalHandlers<T extends AstNode = AstNode> extends SpecificNodeTraversalHandlers {
+    '*'?: NodeTraversalCallback;
+    shouldRun?(ast: T): boolean;
+    init?(ast: T): void;
+  }
+
+  export type TraversalCallback<T extends AstNode = AstNode> = (path: NodePath<T>) => void | boolean;
+
+  export interface TraversalCallbacks<T extends AstNode = AstNode> {
+    pre?: TraversalCallback<T>;
+    post?: TraversalCallback<T>;
+  }
+
+  export type SpecificTraversalHandlers = {
+    [P in AstClass]?: TraversalCallback<AstClassMap[P]> | TraversalCallbacks<AstClassMap[P]>;
+  };
+
+  export interface TraversalHandlers<T extends AstNode = AstNode> extends SpecificTraversalHandlers {
+    '*'?: TraversalCallback;
+    shouldRun?(ast: T): boolean;
+    init?(ast: T): void;
+  }
+
+  /**
+   * Traverses a RegExp AST.
+   *
+   * @param handlers Each `handler` is an object containing handler function for needed
+   * node types. The value for a node type may also be an object with functions pre and post.
+	 * This enables more context-aware analyses, e.g. measuring star height.
+   * 
+   * @example
+   * regexpTree.traverse(ast, {
+   *   onChar(node) {
+   *     ...
+   *   },
+   * });
+   */
+  export function traverse<T extends AstNode>(ast: T, handlers: NodeTraversalHandlers<T> | ReadonlyArray<NodeTraversalHandlers<T>>, options: { asNodes: true }): void;
+  export function traverse<T extends AstNode>(ast: T, handlers: TraversalHandlers<T> | ReadonlyArray<TraversalHandlers<T>>, options?: { asNodes?: false }): void;
+
+  export type TransformHandlers<T extends AstNode = AstNode> = TraversalHandlers<T>;
+
+  export class TransformResult<T extends AstNode, E = unknown> {
+      private _ast;
+      private _source;
+      private _string;
+      private _regexp;
+      private _extra;
+      constructor(ast: T, extra?: E);
+      getAST(): T;
+      setExtra(extra: E): void;
+      getExtra(): E;
+      toRegExp(): RegExp;
+      getSource(): string;
+      getFlags(): string;
+      toString(): string;
+  }
+
+  /**
+   * Transforms a regular expression.
+   *
+   * A regexp can be passed in different formats (string, regexp or AST),
+   * applying a set of transformations. It is a convenient wrapper
+   * on top of "parse-traverse-generate" tool chain.
+   */
+  export function transform<T extends AstNode>(ast: T, handlers: TraversalHandlers<T> | ReadonlyArray<TraversalHandlers<T>>): TransformResult<T>;
+  export function transform(regexp: string | RegExp, handlers: TransformHandlers<AstRegExp> | ReadonlyArray<TransformHandlers<AstRegExp>>): TransformResult<AstRegExp>;
+
+  /**
+   * Optimizes a regular expression by replacing some
+   * sub-expressions with their idiomatic patterns.
+   */
+  export function optimize<T extends AstNode>(ast: T, whitelist?: string[]): TransformResult<T>;
+  export function optimize(regexp: string | RegExp, whitelist?: string[]): TransformResult<AstRegExp>;
+
+  /**
+   * Translates a regular expression in new syntax or in new format
+   * into equivalent expressions in old syntax.
+   */
+  export function compatTranspile<T extends AstNode>(ast: T, whitelist?: string[]): TransformResult<T>;
+  export function compatTranspile(regexp: string | RegExp, whitelist?: string[]): TransformResult<AstRegExp>;
+
+  /**
+   * Executes a regular expression on a string.
+   */
+  export function exec(re: string | RegExp, string: string): RegExpExecArray;
+}

node_modules/regexp-tree/index.js

@@ -0,0 +1,8 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+module.exports = require('./dist/regexp-tree');

node_modules/regexp-tree/package.json

@@ -0,0 +1,73 @@
+{
+  "_args": [
+    [
+      "regexp-tree@0.1.13",
+      "E:\\python\\setup-php"
+    ]
+  ],
+  "_from": "regexp-tree@0.1.13",
+  "_id": "regexp-tree@0.1.13",
+  "_inBundle": false,
+  "_integrity": "sha512-hwdV/GQY5F8ReLZWO+W1SRoN5YfpOKY6852+tBFcma72DKBIcHjPRIlIvQN35bCOljuAfP2G2iB0FC/w236mUw==",
+  "_location": "/regexp-tree",
+  "_phantomChildren": {},
+  "_requested": {
+    "type": "version",
+    "registry": true,
+    "raw": "regexp-tree@0.1.13",
+    "name": "regexp-tree",
+    "escapedName": "regexp-tree",
+    "rawSpec": "0.1.13",
+    "saveSpec": null,
+    "fetchSpec": "0.1.13"
+  },
+  "_requiredBy": [
+    "/@babel/plugin-transform-named-capturing-groups-regex"
+  ],
+  "_resolved": "https://registry.npmjs.org/regexp-tree/-/regexp-tree-0.1.13.tgz",
+  "_spec": "0.1.13",
+  "_where": "E:\\python\\setup-php",
+  "author": {
+    "name": "Dmitry Soshnikov"
+  },
+  "bin": {
+    "regexp-tree": "./bin/regexp-tree"
+  },
+  "bugs": {
+    "url": "https://github.com/DmitrySoshnikov/regexp-tree/issues"
+  },
+  "description": "Regular Expressions parser in JavaScript",
+  "devDependencies": {
+    "babel-cli": "^6.26.0",
+    "babel-preset-env": "1.6.1",
+    "babel-preset-flow": "6.23.0",
+    "eslint": "^4.11.0",
+    "jest-cli": "^19.0.2",
+    "prettier": "^1.17.1",
+    "shelljs": "^0.7.8",
+    "syntax-cli": "^0.1.11"
+  },
+  "homepage": "https://github.com/DmitrySoshnikov/regexp-tree",
+  "keywords": [
+    "regexp",
+    "parser",
+    "AST",
+    "tree",
+    "JavaScript",
+    "ECMAScript"
+  ],
+  "license": "MIT",
+  "name": "regexp-tree",
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/DmitrySoshnikov/regexp-tree.git"
+  },
+  "scripts": {
+    "build": "node scripts/build.js",
+    "eslint": "eslint src/ && eslint bin/regexp-tree",
+    "prepublish": "npm run build && npm test",
+    "test": "jest",
+    "watch": "node scripts/build.js --watch"
+  },
+  "version": "0.1.13"
+}