add escapeValue to ParameterBagInterface

src/Symfony/Component/DependencyInjection/ParameterBag/ParameterBag.php

@@ -253,6 +253,27 @@ class ParameterBag implements ParameterBagInterface
         return $this->resolved;
     }
 
+    /**
+     * {@inheritDoc}
+     */
+    public function escapeValue($value)
+    {
+        if (is_string($value)) {
+            return str_replace('%', '%%', $value);
+        }
+
+        if (is_array($value)) {
+            $result = array();
+            foreach ($value as $k => $v) {
+                $result[$k] = $this->escapeValue($v);
+            }
+
+            return $result;
+        }
+
+        return $value;
+    }
+
     private function unescapeValue($value)
     {
         if (is_string($value)) {

src/Symfony/Component/DependencyInjection/ParameterBag/ParameterBagInterface.php

@@ -94,4 +94,13 @@ interface ParameterBagInterface
      * @throws ParameterNotFoundException if a placeholder references a parameter that does not exist
      */
     function resolveValue($value);
+
+    /**
+     * Escape parameter placeholders %
+     *
+     * @param mixed $value
+     *
+     * @return mixed
+     */
+    function escapeValue($value);
 }

src/Symfony/Component/DependencyInjection/Tests/ParameterBag/ParameterBagTest.php

@@ -201,6 +201,22 @@ class ParameterBagTest extends \PHPUnit_Framework_TestCase
         $this->assertEquals(array('bar' => array('ding' => 'I\'m a bar %foo %bar')), $bag->get('foo'), '->resolveValue() supports % escaping by doubling it');
     }
 
+    /**
+     * @covers Symfony\Component\DependencyInjection\ParameterBag\ParameterBag::escapeValue
+     */
+    public function testEscapeValue()
+    {
+        $bag = new ParameterBag();
+
+        $bag->add(array(
+            'foo' => $bag->escapeValue(array('bar' => array('ding' => 'I\'m a bar %foo %bar', 'zero' => null))),
+            'bar' => $bag->escapeValue('I\'m a %foo%'),
+        ));
+
+        $this->assertEquals('I\'m a %%foo%%', $bag->get('bar'), '->escapeValue() escapes % by doubling it');
+        $this->assertEquals(array('bar' => array('ding' => 'I\'m a bar %%foo %%bar', 'zero' => null)), $bag->get('foo'), '->escapeValue() escapes % by doubling it');
+    }
+
     /**
      * @covers Symfony\Component\DependencyInjection\ParameterBag\ParameterBag::resolve
      * @dataProvider stringsWithSpacesProvider