TreeView scrolls to selected path when move-down or move-up are triggered

Atom/src/native_handler.mm

@@ -16,7 +16,7 @@ NSString *stringFromCefV8Value(const CefRefPtr<CefV8Value>& value) {
 NativeHandler::NativeHandler() : CefV8Handler() {  
   m_object = CefV8Value::CreateObject(NULL, NULL);
   
-  const char *functionNames[] = {"exists", "read", "write", "absolute", "list", "isFile", "isDirectory", "remove", "asyncList", "open", "openDialog", "quit", "writeToPasteboard", "readFromPasteboard", "showDevTools", "newWindow", "saveDialog", "exit", "watchPath", "unwatchPath", "makeDirectory", "move", "moveToTrash"};
+  const char *functionNames[] = {"exists", "alert", "read", "write", "absolute", "list", "isFile", "isDirectory", "remove", "asyncList", "open", "openDialog", "quit", "writeToPasteboard", "readFromPasteboard", "showDevTools", "newWindow", "saveDialog", "exit", "watchPath", "unwatchPath", "makeDirectory", "move", "moveToTrash"};
   NSUInteger arrayLength = sizeof(functionNames) / sizeof(const char *);
   for (NSUInteger i = 0; i < arrayLength; i++) {
     const char *functionName = functionNames[i];

spec/extensions/tree-view-spec.coffee

@@ -1,3 +1,5 @@
+$ = require 'jquery'
+_ = require 'underscore'
 TreeView = require 'tree-view'
 RootView = require 'root-view'
 Directory = require 'directory'
@@ -232,6 +234,23 @@ describe "TreeView", ->
           treeView.trigger 'move-up'
           expect(treeView.root).toHaveClass 'selected'
 
+    describe "movement outside of viewable region", ->
+      it "scrolls the tree view to the selected item", ->
+        treeView.height(100)
+        treeView.attachToDom()
+        $(element).view().expand() for element in treeView.find('.directory')
+        expect(treeView.prop('scrollHeight')).toBeGreaterThan treeView.outerHeight()
+
+        treeView.moveDown()
+        expect(treeView.scrollTop()).toBe 0
+
+        entryCount = treeView.find(".entry").length
+        _.times entryCount, -> treeView.moveDown()
+        expect(treeView.scrollBottom()).toBe treeView.prop('scrollHeight')
+
+        _.times entryCount, -> treeView.moveUp()
+        expect(treeView.scrollTop()).toBe 0
+
     describe "tree-view:expand-directory", ->
       describe "when a directory entry is selected", ->
         it "expands the current directory", ->

src/extensions/tree-view/directory-view.coffee

@@ -7,12 +7,13 @@ module.exports =
 class DirectoryView extends View
   @content: ({directory, isExpanded}) ->
     @li class: 'directory entry', =>
-      @div class: 'header', =>
+      @div outlet: 'header', class: 'header', =>
         @span '▸', class: 'disclosure-arrow', outlet: 'disclosureArrow'
         @span directory.getName(), class: 'name'
 
   directory: null
   entries: null
+  header: null
 
   initialize: ({@directory, isExpanded}) ->
     @expand() if isExpanded

src/extensions/tree-view/tree-view.coffee

@@ -76,12 +76,15 @@ class TreeView extends View
     selectedEntry = @selectedEntry()
     if selectedEntry
       if selectedEntry.is('.expanded.directory')
-        return if @selectEntry(selectedEntry.find('.entry:first'))
-      return if @selectEntry(selectedEntry.next())
-      return if @selectEntry(selectedEntry.closest('.directory').next())
+        @selectEntry(selectedEntry.find('.entry:first'))
+      else
+        if not @selectEntry(selectedEntry.next())
+          @selectEntry(selectedEntry.closest('.directory').next())
     else
       @selectEntry(@root)
 
+    @scollToEntry(@selectedEntry())
+
   moveUp: ->
     selectedEntry = @selectedEntry()
     if selectedEntry
@@ -93,6 +96,8 @@ class TreeView extends View
     else
       @selectEntry(@find('.entry').last())
 
+    @scollToEntry(@selectedEntry())
+
   expandDirectory: ->
     selectedEntry = @selectedEntry()
     selectedEntry.view().expand() if (selectedEntry instanceof DirectoryView)
@@ -125,3 +130,13 @@ class TreeView extends View
     @find('.selected').removeClass('selected')
     entry.addClass('selected')
 
+  scollToEntry: (entry) ->
+    displayElement = if (entry instanceof DirectoryView) then entry.header else entry
+
+    top = @scrollTop() + displayElement.position().top
+    bottom = top + displayElement.outerHeight()
+
+    if bottom > @scrollBottom()
+      @scrollBottom(bottom)
+    if top < @scrollTop()
+      @scrollTop(top)