bugfix

src/Intervention/Image/Commands/Argument.php

@@ -52,8 +52,10 @@ class Argument
         $arguments = $this->command->arguments;
 
         if (is_array($arguments)) {
-            return array_key_exists($this->key, $arguments) ? $arguments[$this->key] : $default;
+            return isset($arguments[$this->key]) ? $arguments[$this->key] : $default;
         }
+
+        return $default;
     }
 
     /**

tests/ArgumentTest.php

@@ -397,6 +397,17 @@ class ArgumentTest extends PHPUnit_Framework_TestCase
         $arg->max(10);
     }
 
+    public function testValueDefault()
+    {
+        $arg = new Argument($this->getMockedCommand());
+        $value = $arg->value('foo');
+        $this->assertEquals('foo', $value);
+
+        $arg = new Argument($this->getMockedCommand(array(null)));
+        $value = $arg->value('foo');
+        $this->assertEquals('foo', $value);
+    }
+
     private function validateArgument($argument, $value)
     {
         $this->assertInstanceOf('\Intervention\Image\Commands\Argument', $argument);