Improve readme and workflow

.github/workflows/workflow.yml

@@ -24,7 +24,7 @@ jobs:
       fail-fast: false
       matrix:
         operating-system: [ubuntu-latest, windows-latest, macOS-latest]
-        php-versions: ['5.6', '7.0', '7.1', '7.2', '7.3']
+        php-versions: ['5.6', '7.0', '7.1', '7.2', '7.3', '7.4']
     steps:
       - name: Checkout
         uses: actions/checkout@v1
@@ -61,13 +61,22 @@ jobs:
           ini-values-csv: post_max_size=256M, short_open_tag=On, date.timezone=Asia/Kolkata #optional
 
       - name: Testing PHP version
-        run: php -v
+        run: |
+          php -v
+          php -r "if(strpos(phpversion(), '${{ matrix.php-versions }}') === false) {throw new Exception('Wrong PHP version Installed');}"
+
       - name: Testing Composer version
-        run: composer -V
+        run: |
+          composer -V
+          php -r "if(strpos(@exec('composer -V'), 'Composer version') === false) {throw new Exception('Composer not found');}"
       - name: Testing Extensions
-        run: php -m
+        run: |
+          php -m
+          php -r "if(! extension_loaded('mbstring')) {throw new Exception('mbstring not found');}"
+          php -r "if(! extension_loaded('Xdebug')) {throw new Exception('Xdebug not found');}"
+          php -r "if(phpversion()>=7.1 && ! extension_loaded('pcov')) {throw new Exception('PCOV not found');}"
       - name: Testing ini values
         run: |
-          printf "post_max_size: %s\n" $(php -r "echo ini_get('post_max_size');")
-          printf "short_open_tag: %s\n" $(php -r "echo ini_get('short_open_tag');")
-          printf "date.timezone: %s\n" $(php -r "echo ini_get('date.timezone');")
+          php -r "if(ini_get('post_max_size')!='256M') {throw new Exception('post_max_size not added');}"
+          php -r "if(ini_get('short_open_tag')!=1) {throw new Exception('short_open_tag not added');}"
+          php -r "if(ini_get('date.timezone')!='Asia/Kolkata') {throw new Exception('date.timezone not added');}"