Merge branch 'batch-updates'

src/cursors-component.coffee

@@ -2,14 +2,13 @@ module.exports =
 class CursorsComponent
   oldState: null
 
-  constructor: (@presenter) ->
+  constructor: ->
     @cursorNodesById = {}
     @domNode = document.createElement('div')
     @domNode.classList.add('cursors')
-    @updateSync()
 
-  updateSync: ->
-    newState = @presenter.state.content
+  updateSync: (state) ->
+    newState = state.content
     @oldState ?= {cursors: {}}
 
     # update blink class

src/gutter-component.coffee

@@ -18,10 +18,8 @@ class GutterComponent
     @domNode.addEventListener 'click', @onClick
     @domNode.addEventListener 'mousedown', @onMouseDown
 
-    @updateSync()
-
-  updateSync: ->
-    @newState = @presenter.state.gutter
+  updateSync: (state) ->
+    @newState = state.gutter
     @oldState ?= {lineNumbers: {}}
 
     @appendDummyLineNumber() unless @dummyLineNumberNode?

src/highlights-component.coffee

@@ -5,7 +5,7 @@ module.exports =
 class HighlightsComponent
   oldState: null
 
-  constructor: (@presenter) ->
+  constructor: ->
     @highlightNodesById = {}
     @regionNodesByHighlightId = {}
 
@@ -17,8 +17,8 @@ class HighlightsComponent
       insertionPoint.setAttribute('select', '.underlayer')
       @domNode.appendChild(insertionPoint)
 
-  updateSync: ->
-    newState = @presenter.state.content.highlights
+  updateSync: (state) ->
+    newState = state.content.highlights
     @oldState ?= {}
 
     # remove highlights

src/input-component.coffee

@@ -1,16 +1,15 @@
 module.exports =
 class InputComponent
-  constructor: (@presenter) ->
+  constructor: ->
     @domNode = document.createElement('input')
     @domNode.classList.add('hidden-input')
     @domNode.setAttribute('data-react-skip-selection-restoration', true)
     @domNode.style['-webkit-transform'] = 'translateZ(0)'
     @domNode.addEventListener 'paste', (event) -> event.preventDefault()
-    @updateSync()
 
-  updateSync: ->
+  updateSync: (state) ->
     @oldState ?= {}
-    newState = @presenter.state.hiddenInput
+    newState = state.hiddenInput
 
     if newState.top isnt @oldState.top
       @domNode.style.top = newState.top + 'px'

src/lines-component.coffee

@@ -42,15 +42,13 @@ class LinesComponent
 
       insertionPoint = document.createElement('content')
       insertionPoint.setAttribute('select', 'atom-overlay')
-      @overlayManager = new OverlayManager(@hostElement)
+      @overlayManager = new OverlayManager(@presenter, @hostElement)
       @domNode.appendChild(insertionPoint)
     else
-      @overlayManager = new OverlayManager(@domNode)
+      @overlayManager = new OverlayManager(@presenter, @domNode)
 
-    @updateSync(visible)
-
-  updateSync: ->
-    @newState = @presenter.state.content
+  updateSync: (state) ->
+    @newState = state.content
     @oldState ?= {lines: {}}
 
     if @newState.scrollHeight isnt @oldState.scrollHeight
@@ -81,10 +79,10 @@ class LinesComponent
       @domNode.style.width = @newState.scrollWidth + 'px'
       @oldState.scrollWidth = @newState.scrollWidth
 
-    @cursorsComponent.updateSync()
-    @highlightsComponent.updateSync()
+    @cursorsComponent.updateSync(state)
+    @highlightsComponent.updateSync(state)
 
-    @overlayManager?.render(@presenter)
+    @overlayManager?.render(state)
 
     @oldState.indentGuidesVisible = @newState.indentGuidesVisible
     @oldState.scrollWidth = @newState.scrollWidth

src/overlay-manager.coffee

@@ -1,20 +1,20 @@
 module.exports =
 class OverlayManager
-  constructor: (@container) ->
+  constructor: (@presenter, @container) ->
     @overlayNodesById = {}
 
-  render: (presenter) ->
-    for decorationId, {pixelPosition, item} of presenter.state.content.overlays
-      @renderOverlay(presenter, decorationId, item, pixelPosition)
+  render: (state) ->
+    for decorationId, {pixelPosition, item} of state.content.overlays
+      @renderOverlay(state, decorationId, item, pixelPosition)
 
     for id, overlayNode of @overlayNodesById
-      unless presenter.state.content.overlays.hasOwnProperty(id)
+      unless state.content.overlays.hasOwnProperty(id)
         delete @overlayNodesById[id]
         overlayNode.remove()
 
     return
 
-  renderOverlay: (presenter, decorationId, item, pixelPosition) ->
+  renderOverlay: (state, decorationId, item, pixelPosition) ->
     item = atom.views.getView(item)
     unless overlayNode = @overlayNodesById[decorationId]
       overlayNode = @overlayNodesById[decorationId] = document.createElement('atom-overlay')
@@ -25,15 +25,15 @@ class OverlayManager
     itemHeight = item.offsetHeight
 
 
-    {scrollTop, scrollLeft} = presenter.state.content
+    {scrollTop, scrollLeft} = state.content
 
     left = pixelPosition.left
-    if left + itemWidth - scrollLeft > presenter.contentFrameWidth and left - itemWidth >= scrollLeft
+    if left + itemWidth - scrollLeft > @presenter.contentFrameWidth and left - itemWidth >= scrollLeft
       left -= itemWidth
 
-    top = pixelPosition.top + presenter.lineHeight
-    if top + itemHeight - scrollTop > presenter.height and top - itemHeight - presenter.lineHeight >= scrollTop
-      top -= itemHeight + presenter.lineHeight
+    top = pixelPosition.top + @presenter.lineHeight
+    if top + itemHeight - scrollTop > @presenter.height and top - itemHeight - @presenter.lineHeight >= scrollTop
+      top -= itemHeight + @presenter.lineHeight
 
     overlayNode.style.top = top + 'px'
     overlayNode.style.left = left + 'px'

src/scrollbar-component.coffee

@@ -1,6 +1,6 @@
 module.exports =
 class ScrollbarComponent
-  constructor: ({@presenter, @orientation, @onScroll}) ->
+  constructor: ({@orientation, @onScroll}) ->
     @domNode = document.createElement('div')
     @domNode.classList.add "#{@orientation}-scrollbar"
     @domNode.style['-webkit-transform'] = 'translateZ(0)' # See atom/atom#3559
@@ -12,16 +12,14 @@ class ScrollbarComponent
 
     @domNode.addEventListener 'scroll', @onScrollCallback
 
-    @updateSync()
-
-  updateSync: ->
+  updateSync: (state) ->
     @oldState ?= {}
     switch @orientation
       when 'vertical'
-        @newState = @presenter.state.verticalScrollbar
+        @newState = state.verticalScrollbar
         @updateVertical()
       when 'horizontal'
-        @newState = @presenter.state.horizontalScrollbar
+        @newState = state.horizontalScrollbar
         @updateHorizontal()
 
     if @newState.visible isnt @oldState.visible

src/scrollbar-corner-component.coffee

@@ -1,20 +1,18 @@
 module.exports =
 class ScrollbarCornerComponent
-  constructor: (@presenter) ->
+  constructor: () ->
     @domNode = document.createElement('div')
     @domNode.classList.add('scrollbar-corner')
 
     @contentNode = document.createElement('div')
     @domNode.appendChild(@contentNode)
 
-    @updateSync()
-
-  updateSync: ->
+  updateSync: (state) ->
     @oldState ?= {}
     @newState ?= {}
 
-    newHorizontalState = @presenter.state.horizontalScrollbar
-    newVerticalState = @presenter.state.verticalScrollbar
+    newHorizontalState = state.horizontalScrollbar
+    newVerticalState = state.verticalScrollbar
     @newState.visible = newHorizontalState.visible and newVerticalState.visible
     @newState.height = newHorizontalState.height
     @newState.width = newVerticalState.width

src/text-editor-component.coffee

@@ -64,21 +64,21 @@ class TextEditorComponent
     @scrollViewNode.classList.add('scroll-view')
     @domNode.appendChild(@scrollViewNode)
 
-    @mountGutterComponent() if @presenter.state.gutter.visible
+    @mountGutterComponent() if @presenter.getState().gutter.visible
 
-    @hiddenInputComponent = new InputComponent(@presenter)
+    @hiddenInputComponent = new InputComponent
     @scrollViewNode.appendChild(@hiddenInputComponent.domNode)
 
     @linesComponent = new LinesComponent({@presenter, @hostElement, @useShadowDOM})
     @scrollViewNode.appendChild(@linesComponent.domNode)
 
-    @horizontalScrollbarComponent = new ScrollbarComponent({@presenter, orientation: 'horizontal', onScroll: @onHorizontalScroll})
+    @horizontalScrollbarComponent = new ScrollbarComponent({orientation: 'horizontal', onScroll: @onHorizontalScroll})
     @scrollViewNode.appendChild(@horizontalScrollbarComponent.domNode)
 
-    @verticalScrollbarComponent = new ScrollbarComponent({@presenter, orientation: 'vertical', onScroll: @onVerticalScroll})
+    @verticalScrollbarComponent = new ScrollbarComponent({orientation: 'vertical', onScroll: @onVerticalScroll})
     @domNode.appendChild(@verticalScrollbarComponent.domNode)
 
-    @scrollbarCornerComponent = new ScrollbarCornerComponent(@presenter)
+    @scrollbarCornerComponent = new ScrollbarCornerComponent
     @domNode.appendChild(@scrollbarCornerComponent.domNode)
 
     @observeEditor()
@@ -104,7 +104,7 @@ class TextEditorComponent
 
   updateSync: ->
     @oldState ?= {}
-    @newState = @presenter.state
+    @newState = @presenter.getState()
 
     cursorMoved = @cursorMoved
     selectionChanged = @selectionChanged
@@ -128,18 +128,18 @@ class TextEditorComponent
         else
           @domNode.style.height = ''
 
-    if @presenter.state.gutter.visible
+    if @newState.gutter.visible
       @mountGutterComponent() unless @gutterComponent?
-      @gutterComponent.updateSync()
+      @gutterComponent.updateSync(@newState)
     else
       @gutterComponent?.domNode?.remove()
       @gutterComponent = null
 
-    @hiddenInputComponent.updateSync()
-    @linesComponent.updateSync()
-    @horizontalScrollbarComponent.updateSync()
-    @verticalScrollbarComponent.updateSync()
-    @scrollbarCornerComponent.updateSync()
+    @hiddenInputComponent.updateSync(@newState)
+    @linesComponent.updateSync(@newState)
+    @horizontalScrollbarComponent.updateSync(@newState)
+    @verticalScrollbarComponent.updateSync(@newState)
+    @scrollbarCornerComponent.updateSync(@newState)
 
     if @editor.isAlive()
       @updateParentViewFocusedClassIfNeeded()
@@ -152,7 +152,7 @@ class TextEditorComponent
     @linesComponent.measureCharactersInNewLines() if @isVisible() and not @newState.content.scrollingVertically
 
   mountGutterComponent: ->
-    @gutterComponent = new GutterComponent({@presenter, @editor, onMouseDown: @onGutterMouseDown})
+    @gutterComponent = new GutterComponent({@editor, onMouseDown: @onGutterMouseDown})
     @domNode.insertBefore(@gutterComponent.domNode, @domNode.firstChild)
 
   becameVisible: ->

src/text-editor-presenter.coffee

@@ -26,13 +26,18 @@ class TextEditorPresenter
     @observeConfig()
     @buildState()
     @startBlinkingCursors() if @focused
+    @updating = false
 
   destroy: ->
     @disposables.dispose()
 
+  # Calls your `callback` when some changes in the model occurred and the current state has been updated.
   onDidUpdateState: (callback) ->
     @emitter.on 'did-update-state', callback
 
+  emitDidUpdateState: ->
+    @emitter.emit "did-update-state" if @isBatching()
+
   transferMeasurementsToModel: ->
     @model.setHeight(@explicitHeight) if @explicitHeight?
     @model.setWidth(@contentFrameWidth) if @contentFrameWidth?
@@ -43,6 +48,59 @@ class TextEditorPresenter
     @model.setVerticalScrollbarWidth(@measuredVerticalScrollbarWidth) if @measuredVerticalScrollbarWidth?
     @model.setHorizontalScrollbarHeight(@measuredHorizontalScrollbarHeight) if @measuredHorizontalScrollbarHeight?
 
+  # Private: Determines whether {TextEditorPresenter} is currently batching changes.
+  # Returns a {Boolean}, `true` if is collecting changes, `false` if is applying them.
+  isBatching: ->
+    @updating is false
+
+  # Private: Executes `fn` if `isBatching()` is false, otherwise sets `@[flagName]` to `true` for later processing. In either cases, it calls `emitDidUpdateState`.
+  # * `flagName` {String} name of a property of this presenter
+  # * `fn` {Function} to call when not batching.
+  batch: (flagName, fn) ->
+    if @isBatching()
+      @[flagName] = true
+    else
+      fn.apply(this)
+
+    @emitDidUpdateState()
+
+  # Public: Gets this presenter's state, updating it just in time before returning from this function.
+  # Returns a state {Object}, useful for rendering to screen.
+  getState: ->
+    @updating = true
+
+    @updateFocusedState() if @shouldUpdateFocusedState
+    @updateHeightState() if @shouldUpdateHeightState
+    @updateVerticalScrollState() if @shouldUpdateVerticalScrollState
+    @updateHorizontalScrollState() if @shouldUpdateHorizontalScrollState
+    @updateScrollbarsState() if @shouldUpdateScrollbarsState
+    @updateHiddenInputState() if @shouldUpdateHiddenInputState
+    @updateContentState() if @shouldUpdateContentState
+    @updateDecorations() if @shouldUpdateDecorations
+    @updateLinesState() if @shouldUpdateLinesState
+    @updateCursorsState() if @shouldUpdateCursorsState
+    @updateOverlaysState() if @shouldUpdateOverlaysState
+    @updateGutterState() if @shouldUpdateGutterState
+    @updateLineNumbersState() if @shouldUpdateLineNumbersState
+
+    @shouldUpdateFocusedState = false
+    @shouldUpdateHeightState = false
+    @shouldUpdateVerticalScrollState = false
+    @shouldUpdateHorizontalScrollState = false
+    @shouldUpdateScrollbarsState = false
+    @shouldUpdateHiddenInputState = false
+    @shouldUpdateContentState = false
+    @shouldUpdateDecorations = false
+    @shouldUpdateLinesState = false
+    @shouldUpdateCursorsState = false
+    @shouldUpdateOverlaysState = false
+    @shouldUpdateGutterState = false
+    @shouldUpdateLineNumbersState = false
+
+    @updating = false
+
+    @state
+
   observeModel: ->
     @disposables.add @model.onDidChange =>
       @updateContentDimensions()
@@ -141,18 +199,16 @@ class TextEditorPresenter
     @updateGutterState()
     @updateLineNumbersState()
 
-  updateFocusedState: ->
+  updateFocusedState: -> @batch "shouldUpdateFocusedState", ->
     @state.focused = @focused
 
-  updateHeightState: ->
+  updateHeightState: -> @batch "shouldUpdateHeightState", ->
     if @autoHeight
       @state.height = @contentHeight
     else
       @state.height = null
 
-    @emitter.emit 'did-update-state'
-
-  updateVerticalScrollState: ->
+  updateVerticalScrollState: -> @batch "shouldUpdateVerticalScrollState", ->
     @state.content.scrollHeight = @scrollHeight
     @state.gutter.scrollHeight = @scrollHeight
     @state.verticalScrollbar.scrollHeight = @scrollHeight
@@ -161,18 +217,14 @@ class TextEditorPresenter
     @state.gutter.scrollTop = @scrollTop
     @state.verticalScrollbar.scrollTop = @scrollTop
 
-    @emitter.emit 'did-update-state'
-
-  updateHorizontalScrollState: ->
+  updateHorizontalScrollState: -> @batch "shouldUpdateHorizontalScrollState", ->
     @state.content.scrollWidth = @scrollWidth
     @state.horizontalScrollbar.scrollWidth = @scrollWidth
 
     @state.content.scrollLeft = @scrollLeft
     @state.horizontalScrollbar.scrollLeft = @scrollLeft
 
-    @emitter.emit 'did-update-state'
-
-  updateScrollbarsState: ->
+  updateScrollbarsState: -> @batch "shouldUpdateScrollbarsState", ->
     @state.horizontalScrollbar.visible = @horizontalScrollbarHeight > 0
     @state.horizontalScrollbar.height = @measuredHorizontalScrollbarHeight
     @state.horizontalScrollbar.right = @verticalScrollbarWidth
@@ -181,9 +233,7 @@ class TextEditorPresenter
     @state.verticalScrollbar.width = @measuredVerticalScrollbarWidth
     @state.verticalScrollbar.bottom = @horizontalScrollbarHeight
 
-    @emitter.emit 'did-update-state'
-
-  updateHiddenInputState: ->
+  updateHiddenInputState: -> @batch "shouldUpdateHiddenInputState", ->
     return unless lastCursor = @model.getLastCursor()
 
     {top, left, height, width} = @pixelRectForScreenRange(lastCursor.getScreenRange())
@@ -200,17 +250,14 @@ class TextEditorPresenter
     @state.hiddenInput.height = height
     @state.hiddenInput.width = Math.max(width, 2)
 
-    @emitter.emit 'did-update-state'
-
-  updateContentState: ->
+  updateContentState: -> @batch "shouldUpdateContentState", ->
     @state.content.scrollWidth = @scrollWidth
     @state.content.scrollLeft = @scrollLeft
     @state.content.indentGuidesVisible = not @model.isMini() and @showIndentGuide
     @state.content.backgroundColor = if @model.isMini() then null else @backgroundColor
     @state.content.placeholderText = if @model.isEmpty() then @model.getPlaceholderText() else null
-    @emitter.emit 'did-update-state'
 
-  updateLinesState: ->
+  updateLinesState: -> @batch "shouldUpdateLinesState", ->
     return unless @startRow? and @endRow? and @lineHeight?
 
     visibleLineIds = {}
@@ -235,8 +282,6 @@ class TextEditorPresenter
       unless visibleLineIds.hasOwnProperty(id)
         delete @state.content.lines[id]
 
-    @emitter.emit 'did-update-state'
-
   updateLineState: (row, line) ->
     lineState = @state.content.lines[line.id]
     lineState.screenRow = row
@@ -256,14 +301,10 @@ class TextEditorPresenter
       top: row * @lineHeight
       decorationClasses: @lineDecorationClassesForRow(row)
 
-  updateCursorsState: ->
+  updateCursorsState: -> @batch "shouldUpdateCursorsState", ->
     @state.content.cursors = {}
-
     @updateCursorState(cursor) for cursor in @model.cursors # using property directly to avoid allocation
 
-    @emitter.emit 'did-update-state'
-
-
   updateCursorState: (cursor, destroyOnly = false) ->
     delete @state.content.cursors[cursor.id]
 
@@ -275,7 +316,9 @@ class TextEditorPresenter
     pixelRect.width = @baseCharacterWidth if pixelRect.width is 0
     @state.content.cursors[cursor.id] = pixelRect
 
-  updateOverlaysState: ->
+    @emitDidUpdateState()
+
+  updateOverlaysState: -> @batch "shouldUpdateOverlaysState", ->
     return unless @hasPixelRectRequirements()
 
     visibleDecorationIds = {}
@@ -296,18 +339,15 @@ class TextEditorPresenter
     for id of @state.content.overlays
       delete @state.content.overlays[id] unless visibleDecorationIds[id]
 
-    @emitter.emit "did-update-state"
-
-  updateGutterState: ->
+  updateGutterState: -> @batch "shouldUpdateGutterState", ->
     @state.gutter.visible = not @model.isMini() and (@model.isGutterVisible() ? true) and @showLineNumbers
     @state.gutter.maxLineNumberDigits = @model.getLineCount().toString().length
     @state.gutter.backgroundColor = if @gutterBackgroundColor isnt "rgba(0, 0, 0, 0)"
       @gutterBackgroundColor
     else
       @backgroundColor
-    @emitter.emit "did-update-state"
 
-  updateLineNumbersState: ->
+  updateLineNumbersState: -> @batch "shouldUpdateLineNumbersState", ->
     return unless @startRow? and @endRow? and @lineHeight?
 
     visibleLineNumberIds = {}
@@ -350,8 +390,6 @@ class TextEditorPresenter
     for id of @state.gutter.lineNumbers
       delete @state.gutter.lineNumbers[id] unless visibleLineNumberIds[id]
 
-    @emitter.emit 'did-update-state'
-
   updateStartRow: ->
     return unless @scrollTop? and @lineHeight?
 
@@ -536,7 +574,7 @@ class TextEditorPresenter
       @stoppedScrollingTimeoutId = null
     @stoppedScrollingTimeoutId = setTimeout(@didStopScrolling.bind(this), @stoppedScrollingDelay)
     @state.content.scrollingVertically = true
-    @emitter.emit 'did-update-state'
+    @emitDidUpdateState()
 
   didStopScrolling: ->
     @state.content.scrollingVertically = false
@@ -545,7 +583,7 @@ class TextEditorPresenter
       @updateLinesState()
       @updateLineNumbersState()
     else
-      @emitter.emit 'did-update-state'
+      @emitDidUpdateState()
 
   setScrollLeft: (scrollLeft) ->
     scrollLeft = @constrainScrollLeft(scrollLeft)
@@ -809,7 +847,7 @@ class TextEditorPresenter
       decorationState.flashCount++
       decorationState.flashClass = flash.class
       decorationState.flashDuration = flash.duration
-      @emitter.emit "did-update-state"
+      @emitDidUpdateState()
 
   didAddDecoration: (decoration) ->
     @observeDecoration(decoration)
@@ -823,7 +861,7 @@ class TextEditorPresenter
     else if decoration.isType('overlay')
       @updateOverlaysState()
 
-  updateDecorations: ->
+  updateDecorations: -> @batch "shouldUpdateDecorations", ->
     @lineDecorationsByScreenRow = {}
     @lineNumberDecorationsByScreenRow = {}
     @highlightDecorationsById = {}
@@ -843,7 +881,6 @@ class TextEditorPresenter
       unless visibleHighlights[id]
         delete @state.content.highlights[id]
 
-    @emitter.emit 'did-update-state'
 
   removeFromLineDecorationCaches: (decoration, range) ->
     for row in [range.start.row..range.end.row] by 1
@@ -883,7 +920,7 @@ class TextEditorPresenter
 
     if decoration.isDestroyed() or not marker.isValid() or range.isEmpty() or not range.intersectsRowRange(@startRow, @endRow - 1)
       delete @state.content.highlights[decoration.id]
-      @emitter.emit 'did-update-state'
+      @emitDidUpdateState()
       return
 
     if range.start.row < @startRow
@@ -895,7 +932,7 @@ class TextEditorPresenter
 
     if range.isEmpty()
       delete @state.content.highlights[decoration.id]
-      @emitter.emit 'did-update-state'
+      @emitDidUpdateState()
       return
 
     highlightState = @state.content.highlights[decoration.id] ?= {
@@ -906,8 +943,8 @@ class TextEditorPresenter
     highlightState.class = properties.class
     highlightState.deprecatedRegionClass = properties.deprecatedRegionClass
     highlightState.regions = @buildHighlightRegions(range)
+    @emitDidUpdateState()
 
-    @emitter.emit 'did-update-state'
     true
 
   buildHighlightRegions: (screenRange) ->
@@ -993,10 +1030,10 @@ class TextEditorPresenter
 
   toggleCursorBlink: ->
     @state.content.cursorsVisible = not @state.content.cursorsVisible
-    @emitter.emit 'did-update-state'
+    @emitDidUpdateState()
 
   pauseCursorBlinking: ->
     @stopBlinkingCursors(true)
     @startBlinkingCursorsAfterDelay ?= _.debounce(@startBlinkingCursors, @getCursorBlinkResumeDelay())
     @startBlinkingCursorsAfterDelay()
-    @emitter.emit 'did-update-state'
+    @emitDidUpdateState()

src/text-editor.coffee

@@ -834,7 +834,8 @@ class TextEditor extends Model
   #      argument will be a {Selection} and the second argument will be the
   #      {Number} index of that selection.
   mutateSelectedText: (fn) ->
-    @transact => fn(selection, index) for selection, index in @getSelections()
+    @mergeIntersectingSelections =>
+      @transact => fn(selection, index) for selection, index in @getSelections()
 
   # Move lines intersection the most recent selection up by one row in screen
   # coordinates.
@@ -993,17 +994,18 @@ class TextEditor extends Model
   # selections to create multiple single-line selections that cumulatively cover
   # the same original area.
   splitSelectionsIntoLines: ->
-    for selection in @getSelections()
-      range = selection.getBufferRange()
-      continue if range.isSingleLine()
+    @mergeIntersectingSelections =>
+      for selection in @getSelections()
+        range = selection.getBufferRange()
+        continue if range.isSingleLine()
 
-      selection.destroy()
-      {start, end} = range
-      @addSelectionForBufferRange([start, [start.row, Infinity]])
-      {row} = start
-      while ++row < end.row
-        @addSelectionForBufferRange([[row, 0], [row, Infinity]])
-      @addSelectionForBufferRange([[end.row, 0], [end.row, end.column]]) unless end.column is 0
+        selection.destroy()
+        {start, end} = range
+        @addSelectionForBufferRange([start, [start.row, Infinity]])
+        {row} = start
+        while ++row < end.row
+          @addSelectionForBufferRange([[row, 0], [row, Infinity]])
+        @addSelectionForBufferRange([[end.row, 0], [end.row, end.column]]) unless end.column is 0
 
   # Extended: For each selection, transpose the selected text.
   #
@@ -1140,7 +1142,8 @@ class TextEditor extends Model
   #   with a positive `groupingInterval` is committed while the previous transaction is
   #   still 'groupable', the two transactions are merged with respect to undo and redo.
   # * `fn` A {Function} to call inside the transaction.
-  transact: (groupingInterval, fn) -> @buffer.transact(groupingInterval, fn)
+  transact: (groupingInterval, fn) ->
+    @buffer.transact(groupingInterval, fn)
 
   # Deprecated: Start an open-ended transaction.
   beginTransaction: (groupingInterval) -> @buffer.beginTransaction(groupingInterval)
@@ -2228,6 +2231,7 @@ class TextEditor extends Model
 
     [head, tail...] = @getSelectionsOrderedByBufferPosition()
     _.reduce(tail, reducer, [head])
+    return result if fn?
 
   # Add a {Selection} based on the given {Marker}.
   #