Making calls to Entity::error() not overwrite by default previous errors

src/Datasource/EntityInterface.php

@@ -173,9 +173,10 @@ public function validate(Validator $validator);
  *
  * @param string|array $field The field to get errors for.
  * @param string|array $errors The errors to be set for $field
+ * @param bool $overwrite Whether or not to overwite pre-existing errors for $field
  * @return array|\Cake\Datasource\EntityInterface
  */
-	public function errors($field = null, $errors = null);
+	public function errors($field = null, $errors = null, $overwrite = false);
 
 /**
  * Stores whether or not a property value can be changed or set in this entity.

src/Datasource/EntityTrait.php

@@ -630,9 +630,10 @@ public function validate(Validator $validator) {
  *
  * @param string|array $field The field to get errors for, or the array of errors to set.
  * @param string|array $errors The errors to be set for $field
+ * @param bool $overwrite Whether or not to overwite pre-existing errors for $field
  * @return array|$this
  */
-	public function errors($field = null, $errors = null) {
+	public function errors($field = null, $errors = null, $overwrite = false) {
 		if ($field === null) {
 			return $this->_errors;
 		}
@@ -650,8 +651,12 @@ public function errors($field = null, $errors = null) {
 		}
 
 		foreach ($field as $f => $error) {
-			$this->_errors[$f] = (array)$error;
+			$this->_errors += [$f => []];
+			$this->_errors[$f] = $overwrite ?
+				(array)$error :
+				array_merge($this->_errors[$f], (array)$error);
 		}
+
 		return $this;
 	}
 

tests/TestCase/ORM/EntityTest.php

@@ -802,16 +802,16 @@ public function testErrors() {
 		$this->assertEquals([], $entity->errors('boo'));
 
 		$entity->errors('foo', 'other error');
-		$this->assertEquals(['other error'], $entity->errors('foo'));
+		$this->assertEquals(['bar', 'other error'], $entity->errors('foo'));
 
 		$entity->errors('bar', ['something', 'bad']);
 		$this->assertEquals(['something', 'bad'], $entity->errors('bar'));
 
-		$expected = ['foo' => ['other error'], 'bar' => ['something', 'bad']];
+		$expected = ['foo' => ['bar', 'other error'], 'bar' => ['something', 'bad']];
 		$this->assertEquals($expected, $entity->errors());
 
 		$errors = ['foo' => ['something'], 'bar' => 'else', 'baz' => ['error']];
-		$this->assertSame($entity, $entity->errors($errors));
+		$this->assertSame($entity, $entity->errors($errors, null, true));
 		$errors['bar'] = ['else'];
 		$this->assertEquals($errors, $entity->errors());
 	}