Only one visible cursor causes the editor to scroll

spec/app/cursor-spec.coffee

@@ -12,7 +12,7 @@ describe "Cursor", ->
     editor = new Editor
     editor.enableKeymap()
     editor.setBuffer(buffer)
-    cursor = editor.find('.cursor').view()
+    cursor = editor.getCursors()[0]
 
   describe "adding and removing of the idle class", ->
     it "removes the idle class while moving, then adds it back when it stops", ->
@@ -43,3 +43,45 @@ describe "Cursor", ->
       cursor.setScreenPosition([1,30])
       expect(cursor.isOnEOL()).toBeTruthy()
 
+  describe "vertical auto scroll", ->
+    beforeEach ->
+      editor.attachToDom()
+      editor.focus()
+      editor.vScrollMargin = 2
+
+    it "only attempts to scroll when a cursor is visible", ->
+      setEditorWidthInChars(editor, 20)
+      setEditorHeightInChars(editor, 10)
+      editor.setCursorBufferPosition([11,0])
+      editor.addCursorAtBufferPosition([0,0])
+      editor.addCursorAtBufferPosition([6,50])
+      window.advanceClock()
+
+      offscreenScrollHandler = spyOn(editor.getCursors()[0], 'autoScrollVertically')
+      onscreenScrollHandler = spyOn(editor.getCursors()[1], 'autoScrollVertically')
+      anotherOffscreenScrollHandler = spyOn(editor.getCursors()[2], 'autoScrollVertically')
+
+      editor.moveCursorRight()
+      window.advanceClock()
+      expect(offscreenScrollHandler).not.toHaveBeenCalled()
+      expect(onscreenScrollHandler).toHaveBeenCalled()
+      expect(anotherOffscreenScrollHandler).not.toHaveBeenCalled()
+
+    it "only attempts to scroll once when multiple cursors are visible", ->
+      setEditorWidthInChars(editor, 20)
+      setEditorHeightInChars(editor, 10)
+      editor.setCursorBufferPosition([11,0])
+      editor.addCursorAtBufferPosition([0,0])
+      editor.addCursorAtBufferPosition([6,0])
+      window.advanceClock()
+
+      offscreenScrollHandler = spyOn(editor.getCursors()[0], 'autoScrollVertically')
+      onscreenScrollHandler = spyOn(editor.getCursors()[1], 'autoScrollVertically')
+      anotherOnscreenScrollHandler = spyOn(editor.getCursors()[2], 'autoScrollVertically')
+
+      editor.moveCursorRight()
+      window.advanceClock()
+      expect(offscreenScrollHandler).not.toHaveBeenCalled()
+      expect(onscreenScrollHandler).toHaveBeenCalled()
+      expect(anotherOnscreenScrollHandler).not.toHaveBeenCalled()
+

spec/app/editor-spec.coffee

@@ -262,10 +262,12 @@ describe "Editor", ->
             expect(editor.scroller.scrollTop()).toBe(0)
 
           it "reduces scroll margins when there isn't enough height to maintain them and scroll smoothly", ->
-            editor.height(editor.lineHeight * 5)
+            setEditorHeightInChars(editor, 5)
+
+            _.times 3, ->
+              editor.moveCursorDown()
+              window.advanceClock()
 
-            _.times 3, -> editor.moveCursorDown()
-            window.advanceClock()
             expect(editor.scroller.scrollTop()).toBe(editor.lineHeight)
 
             editor.moveCursorUp()
@@ -1920,8 +1922,8 @@ describe "Editor", ->
 
     it "returns correct bounds based on scroll position", ->
       expect(editor.bounds()).toEqual [[0,0], [10, 10]]
-      editor.scrollTop(editor.lineHeight * 1)
-      editor.horizontalScroller.scrollLeft(editor.charWidth * 1)
+      editor.scroller.scrollTop(editor.lineHeight * 1)
+      editor.scroller.scrollLeft(editor.charWidth * 1)
       expect(editor.bounds()).toEqual [[1,1], [11, 11]]
 
   describe "screenPositionInBounds(screenPosition)", ->

src/app/cursor.coffee

@@ -132,11 +132,21 @@ class Cursor extends View
     @setBufferPosition @editor.getEofPosition()
 
   updateAppearance: ->
-    position = @editor.pixelPositionForScreenPosition(@getScreenPosition())
+    screenPosition = @getScreenPosition()
+    position = @editor.pixelPositionForScreenPosition(screenPosition)
     @css(position)
+
+    if @editor.getCursors().length == 1 or @editor.screenPositionInBounds(screenPosition)
+      @autoScroll(position)
+
+  autoScroll: (position) ->
+    return if @editor._autoScrolling
+
+    @editor._autoScrolling = true
     _.defer =>
-      @autoScrollVertically(position)
-      @autoScrollHorizontally(position)
+       @editor._autoScrolling = false
+       @autoScrollVertically(position)
+       @autoScrollHorizontally(position)
 
   autoScrollVertically: (position) ->
     linesInView = @editor.scroller.height() / @editor.lineHeight

src/app/editor.coffee

@@ -163,10 +163,10 @@ class Editor extends View
     @parents('#root-view').view()
 
   bounds: ->
-    rows = @height() / @lineHeight
-    columns = @horizontalScroller.width() / @charWidth
+    rows = @scroller.height() / @lineHeight
+    columns = @scroller.width() / @charWidth
 
-    start = new Point(@scrollTop() / @lineHeight, @horizontalScroller.scrollLeft() / @charWidth)
+    start = new Point(@scroller.scrollTop() / @lineHeight, @scroller.scrollLeft() / @charWidth)
     end = new Point(start.row + rows, start.column + columns)
 
     new Range(start, end)