Fix whitelist to be modifiable from behaviors to work with validate.

lib/Cake/Model/ModelValidator.php

@@ -249,7 +249,11 @@ public function errors($options = array()) {
 			return $model->validationErrors;
 		}
 
-		$fieldList = isset($options['fieldList']) ? $options['fieldList'] : array();
+		$fieldList = $model->whitelist;
+		if (empty($fieldList) && !empty($options['fieldList'])) {
+			$fieldList = $options['fieldList'];
+		}
+
 		$exists = $model->exists();
 		$methods = $this->getMethods();
 		$fields = $this->_validationList($fieldList);

lib/Cake/Test/Case/Model/ModelValidationTest.php

@@ -612,6 +612,30 @@ public function testValidatesWithAssociations() {
 		$this->assertEquals(0, $joinRecords, 'Records were saved on the join table. %s');
 	}
 
+	public function testValidateWithFieldListAndBehavior() {
+		$TestModel = new ValidationTest1();
+		$TestModel->validate = array(
+			'title' => array(
+				'rule' => 'alphaNumeric',
+				'required' => true
+			),
+			'name' => array(
+				'rule' => 'alphaNumeric',
+				'required' => true
+		));
+		$TestModel->Behaviors->attach('ValidationRule', array('fields' => array('name')));
+
+		$data = array(
+			'title' => '',
+			'name' => '',
+		);
+		$result = $TestModel->save($data, array('fieldList' => array('title')));
+		$this->assertFalse($result);
+
+		$expected = array('title' => array('This field cannot be left blank'), 'name' => array('This field cannot be left blank'));
+		$this->assertEquals($expected, $TestModel->validationErrors);
+	}
+
 /**
  * test that saveAll and with models with validation interact well
  *
@@ -2380,3 +2404,21 @@ public function testValidateManyAtomicFalseDeepTrueWithErrors() {
 	}
 
 }
+
+/**
+ * Behavior for testing validation rules.
+ */
+class ValidationRuleBehavior extends ModelBehavior {
+
+	public function setup(Model $Model, $config = array()) {
+		$this->settings[$Model->alias] = $config;
+	}
+
+	public function beforeValidate(Model $Model, $options = array()) {
+		$fields = $this->settings[$Model->alias]['fields'];
+		foreach ($fields as $field) {
+			$Model->whitelist[] = $field;
+		}
+	}
+
+}