Implement split-left

spec/atom/root-view-spec.coffee

@@ -62,6 +62,33 @@ describe "RootView", ->
         expect(editor1.lines.find('.line:first').text()).toContain 'ABC'
         expect(editor2.lines.find('.line:first').text()).toContain 'ABC'
 
+    describe "when split-left is triggered on the editor", ->
+      it "places the a new editor to the left of the current editor in a .horizontal div, and focuses the new editor", ->
+        rootView.attachToDom()
+
+        expect(rootView.find('.horizontal')).not.toExist()
+
+        editor1 = rootView.find('.editor').view()
+        editor1.setBuffer(new Buffer(require.resolve 'fixtures/sample.js'))
+        editor1.setCursorScreenPosition([3, 2])
+        editor1.trigger 'split-left'
+
+        expect(rootView.find('.horizontal')).toExist()
+        expect(rootView.find('.horizontal .editor').length).toBe 2
+        expect(rootView.find('.horizontal .editor:eq(1)').view()).toBe editor1
+        editor2 = rootView.find('.horizontal .editor:eq(0)').view()
+        expect(editor2.buffer).toBe editor1.buffer
+        expect(editor2.getCursorScreenPosition()).toEqual [3, 2]
+        expect(editor1).toHaveClass 'split'
+        expect(editor2).toHaveClass 'split'
+
+        expect(editor1.has(':focus')).not.toExist()
+        expect(editor2.has(':focus')).toExist()
+
+        # insertion reflected in both buffers
+        editor1.buffer.insert([0, 0], 'ABC')
+        expect(editor1.lines.find('.line:first').text()).toContain 'ABC'
+        expect(editor2.lines.find('.line:first').text()).toContain 'ABC'
 
   describe ".addPane(view)", ->
     it "adds the given view to the rootView (at the bottom by default)", ->