From 51f45c0f281ea0c1722acb79751e227ba77a2b6a Mon Sep 17 00:00:00 2001
From: mark_story <mark@mark-story.com>
Date: Sat, 14 Jan 2012 22:47:44 -0500
Subject: [PATCH] Moving flatten() across.

It is no longer recursive either.
---
 lib/Cake/Test/Case/Utility/Set2Test.php | 55 +++++++++++++++++++++++++
 lib/Cake/Utility/Set2.php               | 36 +++++++++++++++-
 2 files changed, 90 insertions(+), 1 deletion(-)

diff --git a/lib/Cake/Test/Case/Utility/Set2Test.php b/lib/Cake/Test/Case/Utility/Set2Test.php
index 735916fa4f9..3be7b1676bf 100644
--- a/lib/Cake/Test/Case/Utility/Set2Test.php
+++ b/lib/Cake/Test/Case/Utility/Set2Test.php
@@ -221,4 +221,59 @@ public function testMaxDimensions() {
 		$this->assertEquals($result, 5);
 	}
 
+/**
+ * Tests Set::flatten
+ *
+ * @return void
+ */
+	public function testFlatten() {
+		$data = array('Larry', 'Curly', 'Moe');
+		$result = Set2::flatten($data);
+		$this->assertEquals($result, $data);
+
+		$data[9] = 'Shemp';
+		$result = Set2::flatten($data);
+		$this->assertEquals($result, $data);
+
+		$data = array(
+			array(
+				'Post' => array('id' => '1', 'author_id' => '1', 'title' => 'First Post'),
+				'Author' => array('id' => '1', 'user' => 'nate', 'password' => 'foo'),
+			),
+			array(
+				'Post' => array('id' => '2', 'author_id' => '3', 'title' => 'Second Post', 'body' => 'Second Post Body'),
+				'Author' => array('id' => '3', 'user' => 'larry', 'password' => null),
+			)
+		);
+
+		$result = Set2::flatten($data);
+		$expected = array(
+			'0.Post.id' => '1',
+			'0.Post.author_id' => '1',
+			'0.Post.title' => 'First Post',
+			'0.Author.id' => '1',
+			'0.Author.user' => 'nate',
+			'0.Author.password' => 'foo',
+			'1.Post.id' => '2',
+			'1.Post.author_id' => '3',
+			'1.Post.title' => 'Second Post',
+			'1.Post.body' => 'Second Post Body',
+			'1.Author.id' => '3',
+			'1.Author.user' => 'larry',
+			'1.Author.password' => null
+		);
+		$this->assertEquals($expected, $result);
+
+		$data = array(
+			array('Post' => array('id' => 1)),
+			array('Post' => array('id' => 2)),
+		);
+		$result = Set2::flatten($data, '/');
+		$expected = array(
+			'0/Post/id' => '1',
+			'1/Post/id' => '2',
+		);
+		$this->assertEquals($expected, $result);
+	}
+
 }
diff --git a/lib/Cake/Utility/Set2.php b/lib/Cake/Utility/Set2.php
index 17d4a0f17ad..ea59c9796ea 100644
--- a/lib/Cake/Utility/Set2.php
+++ b/lib/Cake/Utility/Set2.php
@@ -82,8 +82,42 @@ public static function filter(array $data) {
 	
 	}
 
-	public static function flatten(array $data) {
+/**
+ * Collapses a multi-dimensional array into a single dimension, using a delimited array path for
+ * each array element's key, i.e. array(array('Foo' => array('Bar' => 'Far'))) becomes
+ * array('0.Foo.Bar' => 'Far').
+ *
+ * @param array $data Array to flatten
+ * @param string $separator String used to separate array key elements in a path, defaults to '.'
+ * @return array
+ * @link http://book.cakephp.org/2.0/en/core-utility-libraries/set.html#Set::flatten
+ */
+	public static function flatten(array $data, $separator = '.') {
+		$result = array();
+		$stack = array();
+		$path = null;
 
+		reset($data);
+		while (!empty($data)) {
+			$key = key($data);
+			$element = $data[$key];
+			unset($data[$key]);
+
+			if (is_array($element)) {
+				if (!empty($data)) {
+					$stack[] = array($data, $path);
+				}
+				$data = $element;
+				$path .= $key . $separator;
+			} else {
+				$result[$path . $key] = $element;
+			}
+
+			if (empty($data) && !empty($stack)) {
+				list($data, $path) = array_pop($stack);
+			}
+		}
+		return $result;
 	}
 
 	public static function merge(array $data, $merge) {