Prevent code execution in constructor

ReactJS.php

@@ -38,7 +38,19 @@ class ReactJS {
      * Custom error handler
      * @var callable
      */
-    $errorHandler;
+    $errorHandler,
+
+    /**
+     * JS Code to execute only once
+     * @var string
+     */
+    $bootstrap,
+
+    /**
+     * Has the bootstrap JS code been executed ?
+     * @var bool
+     */
+    $booted = false;
 
   /**
    * Initialize by passing JS code as a string.
@@ -59,10 +71,9 @@ function __construct($libsrc, $appsrc) {
     $react[] = $appsrc;
     $react[] = ';';
 
-    $concatenated = implode(";\n", $react);
+    $this->bootstrap = implode(";\n", $react);
 
     $this->v8 = new V8Js();
-    $this->executeJS($concatenated);
   }
 
   /**
@@ -152,6 +163,7 @@ function getJS($where, $return_var = null) {
    */
   private function executeJS($js) {
     try {
+      $this->bootIfRequired();
       ob_start();
       $this->v8->executeString($js);
       return ob_get_clean();
@@ -168,4 +180,13 @@ private function executeJS($js) {
     }
   }
 
+  /**
+   * Execute the bootstrap code if it hasn't been yet
+   */
+  private function bootIfRequired() {
+    if ($this->booted === false) {
+      $this->v8->executeString($this->bootstrap);
+      $this->booted = true;
+    }
+  }
 }