From 2ebfcd174e9e8993ce24d7a073a735310b033f0b Mon Sep 17 00:00:00 2001
From: Bryan Housel <bryan@mapbox.com>
Date: Wed, 3 May 2017 00:21:37 -0400
Subject: [PATCH] Don't redo into un-annotated edit states (closes #4006)

---
 modules/core/history.js   | 16 ++++++++++------
 test/spec/core/history.js | 15 ++++++++++++---
 2 files changed, 22 insertions(+), 9 deletions(-)

diff --git a/modules/core/history.js b/modules/core/history.js
index a7118da76..67ce20290 100644
--- a/modules/core/history.js
+++ b/modules/core/history.js
@@ -173,12 +173,11 @@ export function coreHistory(context) {
         },
 
 
+        // Back to the previous annotated state or index = 0.
         undo: function() {
             d3.select(document).interrupt('history.perform');
 
             var previous = stack[index].graph;
-
-            // Pop to the next annotated state.
             while (index > 0) {
                 index--;
                 if (stack[index].annotation) break;
@@ -189,16 +188,21 @@ export function coreHistory(context) {
         },
 
 
+        // Forward to the next annotated state.
         redo: function() {
             d3.select(document).interrupt('history.perform');
 
             var previous = stack[index].graph;
-            while (index < stack.length - 1) {
-                index++;
-                if (stack[index].annotation) break;
+            var tryIndex = index;
+            while (tryIndex < stack.length - 1) {
+                tryIndex++;
+                if (stack[tryIndex].annotation) {
+                    index = tryIndex;
+                    dispatch.call('redone', this, stack[index]);
+                    break;
+                }
             }
 
-            dispatch.call('redone', this, stack[index]);
             return change(previous);
         },
 
diff --git a/test/spec/core/history.js b/test/spec/core/history.js
index 13734de6e..2d6459f9b 100644
--- a/test/spec/core/history.js
+++ b/test/spec/core/history.js
@@ -214,14 +214,23 @@ describe('iD.History', function () {
             expect(history.redo().changes()).to.eql({});
         });
 
-        it('emits an redone event', function () {
-            history.perform(action);
+        it('does redo into an annotated state', function () {
+            history.perform(action, 'annotation');
+            history.on('redone', spy);
             history.undo();
-            history.on('change', spy);
             history.redo();
+            expect(history.undoAnnotation()).to.equal('annotation');
             expect(spy).to.have.been.called;
         });
 
+        it('does not redo into a non-annotated state', function () {
+            history.perform(action);
+            history.on('redone', spy);
+            history.undo();
+            history.redo();
+            expect(spy).not.to.have.been.called;
+        });
+
         it('emits a change event', function () {
             history.perform(action);
             history.undo();