Implement a Helper method to generate confirm() links

This allows for overriding the default behavior of showing
confirm()-dialogs in Html and Form helpers.

lib/Cake/Test/Case/View/Helper/FormHelperTest.php

@@ -7018,7 +7018,7 @@ public function testPostLink() {
 			),
 			'input' => array('type' => 'hidden', 'name' => '_method', 'value' => 'POST'),
 			'/form',
-			'a' => array('href' => '#', 'onclick' => 'preg:/if \(confirm\('Confirm\?'\)\) \{ document\.post_\w+\.submit\(\); \} event\.returnValue = false; return false;/'),
+			'a' => array('href' => '#', 'onclick' => 'preg:/if \(confirm\("Confirm\?"\)\) \{ document\.post_\w+\.submit\(\); \} event\.returnValue = false; return false;/'),
 			'Delete',
 			'/a'
 		));

lib/Cake/Test/Case/View/Helper/HtmlHelperTest.php

@@ -215,7 +215,7 @@ public function testLink() {
 
 		$result = $this->Html->link('Home', '/home', array('confirm' => 'Are you sure you want to do this?'));
 		$expected = array(
-			'a' => array('href' => '/home', 'onclick' => 'return confirm('Are you sure you want to do this?');'),
+			'a' => array('href' => '/home', 'onclick' => 'if (confirm("Are you sure you want to do this?")) { return true; } return false;'),
 			'Home',
 			'/a'
 		);

lib/Cake/View/Helper.php

@@ -496,6 +496,19 @@ protected function _formatAttribute($key, $value, $escape = true) {
 		return sprintf($this->_attributeFormat, $key, ($escape ? h($value) : $value));
 	}
 
+/**
+ * Returns a string to be used as onclick handler for confirm dialogs.
+ *
+ * @param string $message Message to be displayed
+ * @param string $okCode Code to be executed after user chose 'OK'
+ * @param string $cancelCode Code to be executed after user chose 'Cancel'
+ * @return string onclick JS code
+ */
+	protected function _confirm($message, $okCode, $cancelCode = '') {
+		$message = json_encode($message);
+		return "if (confirm({$message})) { {$okCode} } {$cancelCode}";
+	}
+
 /**
  * Sets this helper's model and field properties to the dot-separated value-pair in $entity.
  *

lib/Cake/View/Helper/FormHelper.php

@@ -1784,12 +1784,11 @@ public function postLink($title, $url = null, $options = array(), $confirmMessag
 		$url = '#';
 		$onClick = 'document.' . $formName . '.submit();';
 		if ($confirmMessage) {
-			$confirmMessage = str_replace(array("'", '"'), array("\'", '\"'), $confirmMessage);
-			$options['onclick'] = "if (confirm('{$confirmMessage}')) { {$onClick} }";
+			$options['onclick'] = $this->_confirm($confirmMessage, $onClick);
 		} else {
-			$options['onclick'] = $onClick;
+			$options['onclick'] = $onClick . ' ';
 		}
-		$options['onclick'] .= ' event.returnValue = false; return false;';
+		$options['onclick'] .= 'event.returnValue = false; return false;';
 
 		$out .= $this->Html->link($title, $url, $options);
 		return $out;

lib/Cake/View/Helper/HtmlHelper.php

@@ -359,15 +359,14 @@ public function link($title, $url = null, $options = array(), $confirmMessage =
 			unset($options['confirm']);
 		}
 		if ($confirmMessage) {
-			$confirmMessage = str_replace("'", "\'", $confirmMessage);
-			$confirmMessage = str_replace('"', '\"', $confirmMessage);
-			$options['onclick'] = "return confirm('{$confirmMessage}');";
+			$options['onclick'] = $this->_confirm($confirmMessage, 'return true;', 'return false;');
 		} elseif (isset($options['default']) && !$options['default']) {
 			if (isset($options['onclick'])) {
-				$options['onclick'] .= ' event.returnValue = false; return false;';
+				$options['onclick'] .= ' ';
 			} else {
-				$options['onclick'] = 'event.returnValue = false; return false;';
+				$options['onclick'] = '';
 			}
+			$options['onclick'] .= 'event.returnValue = false; return false;';
 			unset($options['default']);
 		}
 		return sprintf($this->_tags['link'], $url, $this->_parseAttributes($options), $title);