From 87b9ad36fd72548bf60f62eaa0db130fd6f869d5 Mon Sep 17 00:00:00 2001
From: Matt Esch <matt@mattesch.info>
Date: Sat, 20 Dec 2014 19:03:05 -0800
Subject: [PATCH] correct destroy ordering

---
 test/main.js  | 30 ++++++++++++++++++++++++++++++
 vtree/diff.js | 18 +++++++++---------
 2 files changed, 39 insertions(+), 9 deletions(-)

diff --git a/test/main.js b/test/main.js
index 4cc8d95a..30d666d6 100644
--- a/test/main.js
+++ b/test/main.js
@@ -619,6 +619,36 @@ test("Patch nested widgets", function (assert) {
     assert.end()
 })
 
+test("Can replace stateful widget with vnode", function (assert) {
+    var statefulWidget  = {
+        init: function () {
+            return render(h("div.widget"))
+        },
+        update: function () {},
+        destroy: function () {},
+        type: "Widget"
+    }
+
+    var leftNode = h("div", statefulWidget)
+    var rightNode = h("div", h("div.vnode"))
+
+    var rootNode = render(leftNode)
+
+    assert.equal(rootNode.childNodes.length, 1)
+    assert.equal(rootNode.childNodes[0].className, 'widget')
+
+    var patches = diff(leftNode, rightNode)
+
+    var newRoot = patch(rootNode, patches)
+
+    assert.equal(newRoot, rootNode)
+
+    assert.equal(newRoot.childNodes.length, 1)
+    assert.equal(newRoot.childNodes[0].className, 'vnode')
+
+    assert.end()
+})
+
 test("Ensure children are not rendered more than once", function (assert) {
     var initCount = 0
     var updateCount = 0
diff --git a/vtree/diff.js b/vtree/diff.js
index f5dc9f44..a860b104 100644
--- a/vtree/diff.js
+++ b/vtree/diff.js
@@ -23,6 +23,7 @@ function walk(a, b, patch, index) {
     }
 
     var apply = patch[index]
+    var applyClear = false
 
     if (isThunk(a) || isThunk(b)) {
         thunks(a, b, patch, index)
@@ -49,27 +50,22 @@ function walk(a, b, patch, index) {
                 }
                 apply = diffChildren(a, b, patch, apply, index)
             } else {
-                clearState(a, patch, index)
-                apply = patch[index]
                 apply = appendPatch(apply, new VPatch(VPatch.VNODE, a, b))
+                applyClear = true
             }
         } else {
-            clearState(a, patch, index)
-            apply = patch[index]
             apply = appendPatch(apply, new VPatch(VPatch.VNODE, a, b))
+            applyClear = true
         }
     } else if (isVText(b)) {
         if (!isVText(a)) {
-            clearState(a, patch, index)
-            apply = patch[index]
-            apply = appendPatch(apply, new VPatch(VPatch.VTEXT, a, b))
+            applyClear = true
         } else if (a.text !== b.text) {
             apply = appendPatch(apply, new VPatch(VPatch.VTEXT, a, b))
         }
     } else if (isWidget(b)) {
         if (!isWidget(a)) {
-            clearState(a, patch, index)
-            apply = patch[index]
+            applyClear = true;
         }
 
         apply = appendPatch(apply, new VPatch(VPatch.WIDGET, a, b))
@@ -78,6 +74,10 @@ function walk(a, b, patch, index) {
     if (apply) {
         patch[index] = apply
     }
+
+    if (applyClear) {
+        clearState(a, patch, index)
+    }
 }
 
 function diffProps(a, b) {