[#15] validateInputs must allow ArrayAccess for $data

Per report on #15, the change made in #7 could lead to an issue if $data
is an `ArrayAccess` instance, as `validateInputs()` typehinted on `array`.
This patch adds a test for that condition, and removes the typehint.

src/BaseInputFilter.php

@@ -224,12 +224,12 @@ public function isValid($context = null)
     /**
      * Validate a set of inputs against the current data
      *
-     * @param  array      $inputs
-     * @param  array      $data
+     * @param  array $inputs
+     * @param  array|ArrayAccess $data
      * @param  mixed|null $context
      * @return bool
      */
-    protected function validateInputs(array $inputs, array $data = [], $context = null)
+    protected function validateInputs(array $inputs, $data = [], $context = null)
     {
         // backwards compatibility
         if (empty($data)) {

test/BaseInputFilterTest.php

@@ -9,6 +9,7 @@
 
 namespace ZendTest\InputFilter;
 
+use ArrayObject;
 use PHPUnit_Framework_TestCase as TestCase;
 use stdClass;
 use Zend\InputFilter\Input;
@@ -1096,4 +1097,21 @@ public function testEmptyRequiredValueWithFallbackShouldMarkInputValid()
         $this->assertArrayHasKey('bar', $data);
         $this->assertEquals($bar->getFallbackValue(), $data['bar']);
     }
+
+    /**
+     * @group 15
+     */
+    public function testAllowsValidatingArrayAccessData()
+    {
+        $filter = new InputFilter();
+        $foo = new Input();
+        $foo->getFilterChain()->attachByName('stringtrim')
+                              ->attachByName('alpha');
+        $foo->getValidatorChain()->attach(new Validator\StringLength(3, 6));
+        $filter->add($foo, 'foo');
+
+        $data = new ArrayObject(['foo' => ' valid ']);
+        $filter->setData($data);
+        $this->assertTrue($filter->isValid());
+    }
 }