Fix variable prefix restriction + unit tests

Author: kylekatarnls

src/JsPhpize/Lexer/Scanner.php

@@ -71,8 +71,8 @@ public function scanOperator($matches)
     public function scanVariable($matches)
     {
         $varPrefix = $this->engine->getOption('varPrefix', JsPhpize::VAR_PREFIX);
-        if (substr($matches[0], 0, 5) === $varPrefix) {
-            throw new Exception('Variables cannot start with ' . $varPrefix . ', this prefix is reserved for JsPhpize' . $this->exceptionInfos(), 1);
+        if (strpos($matches[1], $varPrefix) === 0) {
+            throw new Exception('Variables cannot start with ' . $varPrefix . ', this prefix is reserved for JsPhpize' . $this->exceptionInfos(), 4);
         }
 
         return $this->valueToken('variable', $matches);

tests/options.php

@@ -52,4 +52,18 @@ public function testConstPrefixRestriction()
             var a = FOOBAR;
         ');
     }
+
+    /**
+     * @expectedException     \JsPhpize\Lexer\Exception
+     * @expectedExceptionCode 4
+     */
+    public function testVarPrefixRestriction()
+    {
+        $jsPhpize = new JsPhpize(array(
+            'varPrefix' => 'test',
+        ));
+        $jsPhpize->render('
+            var a = test_zz;
+        ');
+    }
 }