setup-python/node_modules/browser-resolve/index.js
Danny McCormick 39c08a0eaa Initial pass
2019-06-26 21:12:00 -04:00

346 lines
9.3 KiB
JavaScript

// builtin
var fs = require('fs');
var path = require('path');
// vendor
var resv = require('resolve');
// given a path, create an array of node_module paths for it
// borrowed from substack/resolve
function nodeModulesPaths (start, cb) {
var splitRe = process.platform === 'win32' ? /[\/\\]/ : /\/+/;
var parts = start.split(splitRe);
var dirs = [];
for (var i = parts.length - 1; i >= 0; i--) {
if (parts[i] === 'node_modules') continue;
var dir = path.join.apply(
path, parts.slice(0, i + 1).concat(['node_modules'])
);
if (!parts[0].match(/([A-Za-z]:)/)) {
dir = '/' + dir;
}
dirs.push(dir);
}
return dirs;
}
function find_shims_in_package(pkgJson, cur_path, shims, browser) {
try {
var info = JSON.parse(pkgJson);
}
catch (err) {
err.message = pkgJson + ' : ' + err.message
throw err;
}
var replacements = getReplacements(info, browser);
// no replacements, skip shims
if (!replacements) {
return;
}
// if browser mapping is a string
// then it just replaces the main entry point
if (typeof replacements === 'string') {
var key = path.resolve(cur_path, info.main || 'index.js');
shims[key] = path.resolve(cur_path, replacements);
return;
}
// http://nodejs.org/api/modules.html#modules_loading_from_node_modules_folders
Object.keys(replacements).forEach(function(key) {
var val;
if (replacements[key] === false) {
val = path.normalize(__dirname + '/empty.js');
}
else {
val = replacements[key];
// if target is a relative path, then resolve
// otherwise we assume target is a module
if (val[0] === '.') {
val = path.resolve(cur_path, val);
}
}
if (key[0] === '/' || key[0] === '.') {
// if begins with / ../ or ./ then we must resolve to a full path
key = path.resolve(cur_path, key);
}
shims[key] = val;
});
[ '.js', '.json' ].forEach(function (ext) {
Object.keys(shims).forEach(function (key) {
if (!shims[key + ext]) {
shims[key + ext] = shims[key];
}
});
});
}
// paths is mutated
// load shims from first package.json file found
function load_shims(paths, browser, cb) {
// identify if our file should be replaced per the browser field
// original filename|id -> replacement
var shims = Object.create(null);
(function next() {
var cur_path = paths.shift();
if (!cur_path) {
return cb(null, shims);
}
var pkg_path = path.join(cur_path, 'package.json');
fs.readFile(pkg_path, 'utf8', function(err, data) {
if (err) {
// ignore paths we can't open
// avoids an exists check
if (err.code === 'ENOENT') {
return next();
}
return cb(err);
}
try {
find_shims_in_package(data, cur_path, shims, browser);
return cb(null, shims);
}
catch (err) {
return cb(err);
}
});
})();
};
// paths is mutated
// synchronously load shims from first package.json file found
function load_shims_sync(paths, browser) {
// identify if our file should be replaced per the browser field
// original filename|id -> replacement
var shims = Object.create(null);
var cur_path;
while (cur_path = paths.shift()) {
var pkg_path = path.join(cur_path, 'package.json');
try {
var data = fs.readFileSync(pkg_path, 'utf8');
find_shims_in_package(data, cur_path, shims, browser);
return shims;
}
catch (err) {
// ignore paths we can't open
// avoids an exists check
if (err.code === 'ENOENT') {
continue;
}
throw err;
}
}
return shims;
}
function build_resolve_opts(opts, base) {
var packageFilter = opts.packageFilter;
var browser = normalizeBrowserFieldName(opts.browser)
opts.basedir = base;
opts.packageFilter = function (info, pkgdir) {
if (packageFilter) info = packageFilter(info, pkgdir);
var replacements = getReplacements(info, browser);
// no browser field, keep info unchanged
if (!replacements) {
return info;
}
info[browser] = replacements;
// replace main
if (typeof replacements === 'string') {
info.main = replacements;
return info;
}
var replace_main = replacements[info.main || './index.js'] ||
replacements['./' + info.main || './index.js'];
info.main = replace_main || info.main;
return info;
};
var pathFilter = opts.pathFilter;
opts.pathFilter = function(info, resvPath, relativePath) {
if (relativePath[0] != '.') {
relativePath = './' + relativePath;
}
var mappedPath;
if (pathFilter) {
mappedPath = pathFilter.apply(this, arguments);
}
if (mappedPath) {
return mappedPath;
}
var replacements = info[browser];
if (!replacements) {
return;
}
mappedPath = replacements[relativePath];
if (!mappedPath && path.extname(relativePath) === '') {
mappedPath = replacements[relativePath + '.js'];
if (!mappedPath) {
mappedPath = replacements[relativePath + '.json'];
}
}
return mappedPath;
};
return opts;
}
function resolve(id, opts, cb) {
// opts.filename
// opts.paths
// opts.modules
// opts.packageFilter
opts = opts || {};
opts.filename = opts.filename || '';
var base = path.dirname(opts.filename);
if (opts.basedir) {
base = opts.basedir;
}
var paths = nodeModulesPaths(base);
if (opts.paths) {
paths.push.apply(paths, opts.paths);
}
paths = paths.map(function(p) {
return path.dirname(p);
});
// we must always load shims because the browser field could shim out a module
load_shims(paths, opts.browser, function(err, shims) {
if (err) {
return cb(err);
}
var resid = path.resolve(opts.basedir || path.dirname(opts.filename), id);
if (shims[id] || shims[resid]) {
var xid = shims[id] ? id : resid;
// if the shim was is an absolute path, it was fully resolved
if (shims[xid][0] === '/') {
return resv(shims[xid], build_resolve_opts(opts, base), function(err, full, pkg) {
cb(null, full, pkg);
});
}
// module -> alt-module shims
id = shims[xid];
}
var modules = opts.modules || Object.create(null);
var shim_path = modules[id];
if (shim_path) {
return cb(null, shim_path);
}
// our browser field resolver
// if browser field is an object tho?
var full = resv(id, build_resolve_opts(opts, base), function(err, full, pkg) {
if (err) {
return cb(err);
}
var resolved = (shims) ? shims[full] || full : full;
cb(null, resolved, pkg);
});
});
};
resolve.sync = function (id, opts) {
// opts.filename
// opts.paths
// opts.modules
// opts.packageFilter
opts = opts || {};
opts.filename = opts.filename || '';
var base = path.dirname(opts.filename);
if (opts.basedir) {
base = opts.basedir;
}
var paths = nodeModulesPaths(base);
if (opts.paths) {
paths.push.apply(paths, opts.paths);
}
paths = paths.map(function(p) {
return path.dirname(p);
});
// we must always load shims because the browser field could shim out a module
var shims = load_shims_sync(paths, opts.browser);
var resid = path.resolve(opts.basedir || path.dirname(opts.filename), id);
if (shims[id] || shims[resid]) {
var xid = shims[id] ? id : resid;
// if the shim was is an absolute path, it was fully resolved
if (shims[xid][0] === '/') {
return resv.sync(shims[xid], build_resolve_opts(opts, base));
}
// module -> alt-module shims
id = shims[xid];
}
var modules = opts.modules || Object.create(null);
var shim_path = modules[id];
if (shim_path) {
return shim_path;
}
// our browser field resolver
// if browser field is an object tho?
var full = resv.sync(id, build_resolve_opts(opts, base));
return (shims) ? shims[full] || full : full;
};
function normalizeBrowserFieldName(browser) {
return browser || 'browser';
}
function getReplacements(info, browser) {
browser = normalizeBrowserFieldName(browser);
var replacements = info[browser] || info.browser;
// support legacy browserify field for easier migration from legacy
// many packages used this field historically
if (typeof info.browserify === 'string' && !replacements) {
replacements = info.browserify;
}
return replacements;
}
module.exports = resolve;