[DI] Allow null as default env value

Author: sroze

ParameterBag/EnvPlaceholderParameterBag.php

@@ -41,8 +41,8 @@ public function get($name)
             if ($this->has($name)) {
                 $defaultValue = parent::get($name);
 
-                if (!is_scalar($defaultValue)) {
-                    throw new RuntimeException(sprintf('The default value of an env() parameter must be scalar, but "%s" given to "%s".', gettype($defaultValue), $name));
+                if (null !== $defaultValue && !is_scalar($defaultValue)) {
+                    throw new RuntimeException(sprintf('The default value of an env() parameter must be scalar or null, but "%s" given to "%s".', gettype($defaultValue), $name));
                 }
             }
 
@@ -96,8 +96,8 @@ public function resolve()
             }
             if (is_numeric($default = $this->parameters[$name])) {
                 $this->parameters[$name] = (string) $default;
-            } elseif (null !== $default && !is_string($default)) {
-                throw new RuntimeException(sprintf('The default value of env parameter "%s" must be string or null, %s given.', $env, gettype($default)));
+            } elseif (null !== $default && !is_scalar($default)) {
+                throw new RuntimeException(sprintf('The default value of env parameter "%s" must be scalar or null, %s given.', $env, gettype($default)));
             }
         }
     }

Tests/ParameterBag/EnvPlaceholderParameterBagTest.php

@@ -130,7 +130,7 @@ public function testResolveEnvAllowsNull()
 
     /**
      * @expectedException \Symfony\Component\DependencyInjection\Exception\RuntimeException
-     * @expectedExceptionMessage The default value of env parameter "ARRAY_VAR" must be string or null, array given.
+     * @expectedExceptionMessage The default value of env parameter "ARRAY_VAR" must be scalar or null, array given.
      */
     public function testResolveThrowsOnBadDefaultValue()
     {
@@ -139,4 +139,26 @@ public function testResolveThrowsOnBadDefaultValue()
         $bag->set('env(Array_Var)', array());
         $bag->resolve();
     }
+
+    public function testGetEnvAllowsNull()
+    {
+        $bag = new EnvPlaceholderParameterBag();
+        $bag->set('env(NULL_VAR)', null);
+        $bag->get('env(NULL_VAR)');
+        $bag->resolve();
+
+        $this->assertNull($bag->all()['env(null_var)']);
+    }
+
+    /**
+     * @expectedException \Symfony\Component\DependencyInjection\Exception\RuntimeException
+     * @expectedExceptionMessage The default value of an env() parameter must be scalar or null, but "array" given to "env(ARRAY_VAR)".
+     */
+    public function testGetThrowsOnBadDefaultValue()
+    {
+        $bag = new EnvPlaceholderParameterBag();
+        $bag->set('env(ARRAY_VAR)', array());
+        $bag->get('env(ARRAY_VAR)');
+        $bag->resolve();
+    }
 }