Avoid string literals with double quotes (#37)

Author: MidnightDesign

Eventjet/ruleset.xml

@@ -92,6 +92,9 @@
     </rule>
     <rule ref="Generic.Strings.UnnecessaryStringConcat"/>
 
+    <!-- Avoid double quotes -->
+    <rule ref="Squiz.Strings.DoubleQuoteUsage"/>
+
     <!-- Forbid spaces in type casts -->
     <rule ref="Squiz.WhiteSpace.CastSpacing"/>
 

php-cs-fixer-rules.php

@@ -72,6 +72,7 @@
     ],
     'phpdoc_trim' => true,
     'php_unit_data_provider_static' => true,
+    'single_quote' => true,
     'single_space_around_construct' => true,
     'strict_comparison' => true,
     'trailing_comma_in_multiline' => [

tests/fixtures/invalid/double-quotes.php

@@ -0,0 +1,5 @@
+<?php
+
+declare(strict_types=1);
+
+echo "double quotes";

tests/fixtures/valid/single-quotes.php

@@ -0,0 +1,5 @@
+<?php
+
+declare(strict_types=1);
+
+echo 'single quotes';