From 2afd0171a1369d652acaceaeb3572c62b1eda1e3 Mon Sep 17 00:00:00 2001
From: Batalov Sergey <firstfire@list.ru>
Date: Tue, 19 Jul 2016 09:27:58 +0500
Subject: [PATCH 1/2] Scroll toolbox with LEFT/RIGHT in horizontalLayout

---
 core/toolbox.js | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/core/toolbox.js b/core/toolbox.js
index ac15ed128..ba47a6fe6 100644
--- a/core/toolbox.js
+++ b/core/toolbox.js
@@ -542,6 +542,7 @@ Blockly.Toolbox.TreeControl.prototype.setSelectedItem = function(node) {
 Blockly.Toolbox.TreeNode = function(toolbox, html, opt_config, opt_domHelper) {
   goog.ui.tree.TreeNode.call(this, html, opt_config, opt_domHelper);
   if (toolbox) {
+    this.horizontalLayout_ = toolbox.horizontalLayout_;
     var resize = function() {
       // Even though the div hasn't changed size, the visible workspace
       // surface of the workspace has, so we may need to reposition everything.
@@ -593,6 +594,28 @@ Blockly.Toolbox.TreeNode.prototype.onDoubleClick_ = function(e) {
   // NOP.
 };
 
+/**
+ * Remap event.keyCode in horizontalLayout so that arrow
+ * keys work properly and call original onKeyDown handler.
+ * @param {!goog.events.BrowserEvent} e The browser event.
+ * @return {boolean} The handled value.
+ * @override
+ * @private
+ */
+Blockly.Toolbox.TreeNode.prototype.onKeyDown = function(e) {
+  if (this.horizontalLayout_) {
+    var map = {};
+    map[goog.events.KeyCodes.RIGHT] = goog.events.KeyCodes.DOWN;
+    map[goog.events.KeyCodes.LEFT] = goog.events.KeyCodes.UP;
+    map[goog.events.KeyCodes.UP] = goog.events.KeyCodes.LEFT;
+    map[goog.events.KeyCodes.DOWN] = goog.events.KeyCodes.RIGHT;
+
+    var newKeyCode = map[e.keyCode]
+    e.keyCode = newKeyCode ? newKeyCode : e.keyCode;
+  }
+  return Blockly.Toolbox.TreeNode.superClass_.onKeyDown.call(this, e);
+};
+
 /**
  * A blank separator node in the tree.
  * @param {Object=} config The configuration for the tree. See

From 34530666fba4092437ad0719c9991ffd27fe8efb Mon Sep 17 00:00:00 2001
From: Batalov Sergey <firstfire@list.ru>
Date: Wed, 20 Jul 2016 08:49:28 +0500
Subject: [PATCH 2/2] Small fixes

---
 core/toolbox.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/core/toolbox.js b/core/toolbox.js
index ba47a6fe6..4af1b1dd9 100644
--- a/core/toolbox.js
+++ b/core/toolbox.js
@@ -610,8 +610,8 @@ Blockly.Toolbox.TreeNode.prototype.onKeyDown = function(e) {
     map[goog.events.KeyCodes.UP] = goog.events.KeyCodes.LEFT;
     map[goog.events.KeyCodes.DOWN] = goog.events.KeyCodes.RIGHT;
 
-    var newKeyCode = map[e.keyCode]
-    e.keyCode = newKeyCode ? newKeyCode : e.keyCode;
+    var newKeyCode = map[e.keyCode];
+    e.keyCode = newKeyCode || e.keyCode;
   }
   return Blockly.Toolbox.TreeNode.superClass_.onKeyDown.call(this, e);
 };