added a defined test (strict_variables is now useable)

diff --git a/doc/02-Twig-for-Template-Designers.markdown b/doc/02-Twig-for-Template-Designers.markdown
index 5ab7508..37c2359 100644 (file)
--- a/doc/02-Twig-for-Template-Designers.markdown
+++ b/doc/02-Twig-for-Template-Designers.markdown
@@ -1301,7 +1301,7 @@ variable:
         the foo attribute really is the `false` PHP value
     {% endif %}
 
-### `constant` (new in Twig 0.9.9)
+### `constant`
 
 `constant` checks if a variable has the exact same value as a constant. You
 can use either global constants or class constants:
@@ -1311,6 +1311,11 @@ can use either global constants or class constants:
         the status attribute is exactly the same as Post::PUBLISHED
     {% endif %}
 
+### `defined`
+
+`defined` checks if a variable is defined in the current context. This is very
+useful if you use the `strict_variables` option.
+
 Extensions
 ----------
 

diff --git a/lib/Twig/Extension/Core.php b/lib/Twig/Extension/Core.php
index 84b45ff..97db509 100644 (file)
--- a/lib/Twig/Extension/Core.php
+++ b/lib/Twig/Extension/Core.php
@@ -95,7 +95,7 @@ class Twig_Extension_Core extends Twig_Extension
         return array(
             'even'        => new Twig_Test_Function('twig_test_even'),
             'odd'         => new Twig_Test_Function('twig_test_odd'),
-            //'defined'     => new Twig_Test_Function(),
+            'defined'     => new Twig_Test_Function('twig_test_defined'),
             'sameas'      => new Twig_Test_Function('twig_test_sameas'),
             'none'        => new Twig_Test_Function('twig_test_none'),
             'divisibleby' => new Twig_Test_Function('twig_test_divisibleby'),
@@ -410,3 +410,8 @@ function twig_test_constant($value, $constant)
 {
     return constant($constant) === $value;
 }
+
+function twig_test_defined($name, $context)
+{
+    return array_key_exists($name, $context);
+}

diff --git a/lib/Twig/Node/Expression/Test.php b/lib/Twig/Node/Expression/Test.php
index 1354dc5..50cb293 100644 (file)
--- a/lib/Twig/Node/Expression/Test.php
+++ b/lib/Twig/Node/Expression/Test.php
@@ -22,6 +22,21 @@ class Twig_Node_Expression_Test extends Twig_Node_Expression
             throw new Twig_Error_Syntax(sprintf('The test "%s" does not exist', $this->getAttribute('name')), $this->getLine());
         }
 
+        // defined is a special case
+        if ('defined' === $this->getAttribute('name')) {
+            if (!$this->getNode('node') instanceof Twig_Node_Expression_Name){
+                throw new Twig_Error_Syntax('The "defined" test only works with simple variables', $this->getLine());
+            }
+
+            $compiler
+                ->raw($testMap[$this->getAttribute('name')]->compile().'(')
+                ->repr($this->getNode('node')->getAttribute('name'))
+                ->raw(', $context)')
+            ;
+
+            return;
+        }
+
         $compiler
             ->raw($testMap[$this->getAttribute('name')]->compile().'(')
             ->subcompile($this->getNode('node'))