From 8fc576490432f5fba56cdb52ddcaf0e847238a5b Mon Sep 17 00:00:00 2001
From: Leo Horie <lhorie@klick.com>
Date: Fri, 4 Jul 2014 23:21:08 -0400
Subject: [PATCH] allow mixing keys with non-keyed elements

---
 mithril.js             | 20 ++++++++++++++------
 tests/mithril-tests.js | 17 +++++++++++++++++
 2 files changed, 31 insertions(+), 6 deletions(-)

diff --git a/mithril.js b/mithril.js
index 02286b46..8e398275 100644
--- a/mithril.js
+++ b/mithril.js
@@ -49,7 +49,7 @@ Mithril = m = new function app(window) {
 			var nodes = [], intact = cached.length === data.length, subArrayCount = 0
 			
 			var DELETION = 1, INSERTION = 2 , MOVE = 3
-			var existing = {}, shouldMaintainIdentities = false
+			var existing = {}, unkeyed = [], shouldMaintainIdentities = false
 			for (var i = 0; i < cached.length; i++) {
 				if (cached[i] && cached[i].attrs && cached[i].attrs.key !== undefined) {
 					shouldMaintainIdentities = true
@@ -58,15 +58,18 @@ Mithril = m = new function app(window) {
 			}
 			if (shouldMaintainIdentities) {
 				for (var i = 0; i < data.length; i++) {
-					if (data[i] && data[i].attrs && data[i].attrs.key !== undefined) {
-						var key = data[i].attrs.key
-						if (!existing[key]) existing[key] = {action: INSERTION, index: i}
-						else existing[key] = {action: MOVE, index: i, from: existing[key].index, element: parentElement.childNodes[existing[key].index]}
+					if (data[i] && data[i].attrs) {
+						if (data[i].attrs.key !== undefined) {
+							var key = data[i].attrs.key
+							if (!existing[key]) existing[key] = {action: INSERTION, index: i}
+							else existing[key] = {action: MOVE, index: i, from: existing[key].index, element: parentElement.childNodes[existing[key].index]}
+						}
+						else unkeyed.push({index: i, element: parentElement.childNodes[i]})
 					}
 				}
 				var actions = Object.keys(existing).map(function(key) {return existing[key]})
 				var changes = actions.sort(function(a, b) {return a.action - b.action || b.index - a.index})
-				var newCached = new Array(cached.length)
+				var newCached = cached.slice()
 				
 				for (var i = 0, change; change = changes[i]; i++) {
 					if (change.action == DELETION) {
@@ -87,6 +90,11 @@ Mithril = m = new function app(window) {
 						newCached[change.index] = cached[change.from]
 					}
 				}
+				for (var i = 0; i < unkeyed.length; i++) {
+					var change = unkeyed[i]
+					parentElement.insertBefore(change.element, parentElement.childNodes[change.index])
+					newCached[change.index] = cached[change.index]
+				}
 				cached = newCached
 				cached.nodes = []
 				for (var i = 0, child; child = parentElement.childNodes[i]; i++) cached.nodes.push(child)
diff --git a/tests/mithril-tests.js b/tests/mithril-tests.js
index 3df6dd0d..1e0efded 100644
--- a/tests/mithril-tests.js
+++ b/tests/mithril-tests.js
@@ -563,6 +563,23 @@ function testMithril(mock) {
 		var fourthAfter = root.childNodes[0]
 		return firstBefore === firstAfter && secondBefore === secondAfter && fourthBefore === fourthAfter && root.childNodes[1].key == "10" && root.childNodes[4].key == "6" && root.childNodes[5].key == "7" && root.childNodes.length === 6
 	})
+	test(function() {
+		//https://github.com/lhorie/mithril.js/issues/149
+		var root = mock.document.createElement("div")
+		m.render(root, [m("a", {key: 1}), m("a", {key: 2}), m("a"), m("a", {key: 4}), m("a", {key: 5})])
+		var firstBefore = root.childNodes[0]
+		var secondBefore = root.childNodes[1]
+		var thirdBefore = root.childNodes[2]
+		var fourthBefore = root.childNodes[3]
+		var fifthBefore = root.childNodes[4]
+		m.render(root, [m("a", {key: 4}), m("a", {key: 5}), m("a"), m("a", {key: 1}), m("a", {key: 2})])
+		var firstAfter = root.childNodes[3]
+		var secondAfter = root.childNodes[4]
+		var thirdAfter = root.childNodes[2]
+		var fourthAfter = root.childNodes[0]
+		var fifthAfter = root.childNodes[1]
+		return firstBefore === firstAfter && secondBefore === secondAfter && thirdBefore === thirdAfter && fourthBefore === fourthAfter && fifthBefore === fifthAfter
+	})
 	test(function() {
 		//https://github.com/lhorie/mithril.js/issues/134
 		var root = mock.document.createElement("div")