           editor.trigger 'editor:duplicate-line'
           expect(buffer.lineForRow(13)).toBe ''
           expect(buffer.lineForRow(14)).toBe ''
-          expect(buffer.lineForRow(15)).toBeNull()
+          expect(buffer.lineForRow(15)).toBeUndefined()
           expect(editor.getCursorBufferPosition()).toEqual [14, 0]
 
       describe "when the cursor is on the second to last line and the last line only a newline", ->

          editor.trigger 'editor:duplicate-line'
          expect(buffer.lineForRow(12)).toBe '};'
          expect(buffer.lineForRow(13)).toBe '};'
          expect(buffer.lineForRow(14)).toBeNull()
          expect(editor.getCursorBufferPosition()).toEqual [13, 2]

      describe "when the cursor in on the last line and it is only a newline", ->

        editor.trigger 'editor:move-line-down'
        expect(buffer.lineForRow(11)).toBe '};'
        expect(buffer.lineForRow(12)).toBe '  return sort(Array.apply(this, arguments));'
        expect(buffer.lineForRow(13)).toBeUndefined()

    describe "when the cursor is on the second to last line and the last line is empty", ->
      it "does not move the line", ->
