renderer tells editor when the gutter needs to be updated

benchmark/benchmark-suite.coffee

@@ -27,7 +27,7 @@ describe "editor.", ->
       editor.setBuffer new Buffer(require.resolve('fixtures/medium.coffee'))
 
     describe "at-begining.", ->
-      benchmark "insert-delete", ->
+      fbenchmark "insert-delete", ->
         editor.insertText('x')
         editor.backspace()
 

spec/app/editor-spec.coffee

@@ -583,11 +583,19 @@ describe "Editor", ->
         expect(editor.gutter.find('.line-number:eq(5)').text()).toBe '5'
 
     describe "when there are folds", ->
-      it "skips line numbers", ->
+      it "skips line numbers covered by the fold and updates them when the fold changes", ->
         editor.createFold(3, 5)
         expect(editor.gutter.find('.line-number:eq(3)').text()).toBe '4'
         expect(editor.gutter.find('.line-number:eq(4)').text()).toBe '7'
 
+        buffer.insert([4,0], "\n\n")
+        expect(editor.gutter.find('.line-number:eq(3)').text()).toBe '4'
+        expect(editor.gutter.find('.line-number:eq(4)').text()).toBe '9'
+
+        buffer.delete([[3,0], [6,0]])
+        expect(editor.gutter.find('.line-number:eq(3)').text()).toBe '4'
+        expect(editor.gutter.find('.line-number:eq(4)').text()).toBe '6'
+
     describe "when the scrollView is scrolled to the right", ->
       it "adds a drop shadow to the gutter", ->
         editor.attachToDom()

spec/app/renderer-spec.coffee

@@ -10,6 +10,13 @@ describe "Renderer", ->
     changeHandler = jasmine.createSpy 'changeHandler'
     renderer.on 'change', changeHandler
 
+  describe "when the buffer changes", ->
+    it "renders line numbers correctly", ->
+      originalLineCount = renderer.lineCount()
+      oneHundredLines = [0..100].join("\n")
+      buffer.insert([0,0], oneHundredLines)
+      expect(renderer.lineCount()).toBe 100 + originalLineCount
+
   describe "soft wrapping", ->
     beforeEach ->
       renderer.setMaxLineLength(50)
@@ -55,6 +62,7 @@ describe "Renderer", ->
             [[event]]= changeHandler.argsForCall
             expect(event.oldRange).toEqual([[7, 0], [8, 20]])
             expect(event.newRange).toEqual([[7, 0], [7, 47]])
+            expect(event.lineNumbersChanged).toBeTruthy()
 
         describe "when the update causes a line to softwrap an additional time", ->
           it "rewraps the line and emits a change event", ->
@@ -68,6 +76,7 @@ describe "Renderer", ->
             [[event]] = changeHandler.argsForCall
             expect(event.oldRange).toEqual([[7, 0], [8, 20]])
             expect(event.newRange).toEqual([[7, 0], [9, 20]])
+            expect(event.lineNumbersChanged).toBeTruthy()
 
       describe "when buffer lines are inserted", ->
         it "inserts / updates wrapped lines and emits a change event", ->
@@ -81,6 +90,7 @@ describe "Renderer", ->
           [event] = changeHandler.argsForCall[0]
           expect(event.oldRange).toEqual([[7, 0], [8, 20]])
           expect(event.newRange).toEqual([[7, 0], [10, 20]])
+          expect(event.lineNumbersChanged).toBeTruthy()
 
       describe "when buffer lines are removed", ->
         it "removes lines and emits a change event", ->
@@ -94,6 +104,7 @@ describe "Renderer", ->
           [event] = changeHandler.argsForCall[0]
           expect(event.oldRange).toEqual([[3, 0], [11, 45]])
           expect(event.newRange).toEqual([[3, 0], [5, 45]])
+          expect(event.lineNumbersChanged).toBeTruthy()
 
     describe "position translation", ->
       it "translates positions accounting for wrapped lines", ->
@@ -128,6 +139,7 @@ describe "Renderer", ->
         [event] = changeHandler.argsForCall[0]
         expect(event.oldRange).toEqual([[0, 0], [15, 2]])
         expect(event.newRange).toEqual([[0, 0], [18, 2]])
+        expect(event.lineNumbersChanged).toBeTruthy()
 
   describe "folding", ->
     beforeEach ->
@@ -151,6 +163,7 @@ describe "Renderer", ->
           [event] = changeHandler.argsForCall[0]
           expect(event.oldRange).toEqual [[4, 0], [7, 1]]
           expect(event.newRange).toEqual [[4, 0], [4, 101]]
+          expect(event.lineNumbersChanged).toBeTruthy()
           changeHandler.reset()
 
           fold.destroy()
@@ -165,6 +178,7 @@ describe "Renderer", ->
           [[event]] = changeHandler.argsForCall
           expect(event.oldRange).toEqual [[4, 0], [4, 101]]
           expect(event.newRange).toEqual [[4, 0], [7, 1]]
+          expect(event.lineNumbersChanged).toBeTruthy()
 
       describe "when a fold spans a single line", ->
         it "renders a fold placeholder for the folded line but does not skip any lines", ->
@@ -181,6 +195,10 @@ describe "Renderer", ->
           [[event]] = changeHandler.argsForCall
           expect(event.oldRange).toEqual [[4, 0], [4, 101]]
           expect(event.newRange).toEqual [[4, 0], [4, 101]]
+
+          # Line numbers don't actually change, but it's not worth the complexity to have this
+          # be false for single line folds since they are so rare
+          expect(event.lineNumbersChanged).toBeTruthy()
           changeHandler.reset()
 
           fold.destroy()
@@ -196,6 +214,7 @@ describe "Renderer", ->
           [[event]] = changeHandler.argsForCall
           expect(event.oldRange).toEqual [[4, 0], [4, 101]]
           expect(event.newRange).toEqual [[4, 0], [4, 101]]
+          expect(event.lineNumbersChanged).toBeTruthy()
           changeHandler.reset()
 
       describe "when a fold is nested within another fold", ->
@@ -255,6 +274,7 @@ describe "Renderer", ->
           [[event]] = changeHandler.argsForCall
           expect(event.oldRange).toEqual [[1, 0], [3, 1]]
           expect(event.newRange).toEqual [[1, 0], [1, 6]]
+          expect(event.lineNumbersChanged).toBeTruthy()
 
       describe "when the old range surrounds two nested folds", ->
         it "removes both folds and replaces the selection with the new text", ->
@@ -271,6 +291,7 @@ describe "Renderer", ->
           [[event]] = changeHandler.argsForCall
           expect(event.oldRange).toEqual [[1, 0], [3, 2]]
           expect(event.newRange).toEqual [[1, 0], [1, 9]]
+          expect(event.lineNumbersChanged).toBeTruthy()
 
       describe "when the old range precedes lines with a fold", ->
         it "updates the buffer and re-positions subsequent folds", ->
@@ -286,6 +307,7 @@ describe "Renderer", ->
           [[event]] = changeHandler.argsForCall
           expect(event.oldRange).toEqual [[0, 0], [1, 1]]
           expect(event.newRange).toEqual [[0, 0], [0, 3]]
+          expect(event.lineNumbersChanged).toBeTruthy()
           changeHandler.reset()
 
           fold1.destroy()
@@ -300,6 +322,7 @@ describe "Renderer", ->
           [[event]] = changeHandler.argsForCall
           expect(event.oldRange).toEqual [[1, 0], [1, 1]]
           expect(event.newRange).toEqual [[1, 0], [3, 101]]
+          expect(event.lineNumbersChanged).toBeTruthy()
 
       describe "when the old range straddles the beginning of a fold", ->
         it "replaces lines in the portion of the range that precedes the fold and adjusts the end of the fold to encompass additional lines", ->
@@ -326,6 +349,7 @@ describe "Renderer", ->
           [[event]] = changeHandler.argsForCall
           expect(event.oldRange).toEqual [[6, 0], [7, 2]] # Expands ranges to encompes entire line
           expect(event.newRange).toEqual [[6, 0], [6, 5]]
+          expect(event.lineNumbersChanged).toBeTruthy()
 
       describe "when the old range is inside a fold", ->
         describe "when the end of the new range precedes the end of the fold", ->
@@ -346,6 +370,7 @@ describe "Renderer", ->
             [[event]] = changeHandler.argsForCall
             expect(event.oldRange).toEqual [[2, 0], [2, 1]]
             expect(event.newRange).toEqual [[2, 0], [2, 1]]
+            expect(event.lineNumbersChanged).toBeTruthy()
 
         describe "when the end of the new range exceeds the end of the fold", ->
           it "expands the fold to contain all the inserted lines", ->
@@ -365,6 +390,7 @@ describe "Renderer", ->
             [[event]] = changeHandler.argsForCall
             expect(event.oldRange).toEqual [[2, 0], [2, 1]]
             expect(event.newRange).toEqual [[2, 0], [2, 1]]
+            expect(event.lineNumbersChanged).toBeTruthy()
 
       describe "when the old range straddles the end of the fold", ->
         describe "when the end of the new range precedes the end of the fold", ->
@@ -390,6 +416,7 @@ describe "Renderer", ->
           [[event]] = changeHandler.argsForCall
           expect(event.oldRange).toEqual [[3, 0], [3, 1]]
           expect(event.newRange).toEqual [[3, 0], [4, 1]]
+          expect(event.lineNumbersChanged).toBeTruthy()
 
     describe "position translation", ->
       it "translates positions to account for folded lines and characters and the placeholder", ->

src/app/editor.coffee

@@ -424,7 +424,7 @@ class Editor extends View
     @compositeCursor.updateBufferPosition() unless e.bufferChanged
 
     if @attached
-      unless newScreenRange.isSingleLine() and newScreenRange.coversSameRows(oldScreenRange)
+      if e.lineNumbersChanged
         @gutter.renderLineNumbers(@getFirstVisibleScreenRow(), @getLastVisibleScreenRow())
 
       @verticalScrollbarContent.height(@lineHeight * @screenLineCount())
@@ -454,7 +454,7 @@ class Editor extends View
 
       if rowDelta > 0
         @removeLineElements(@lastRenderedScreenRow + 1, @lastRenderedScreenRow + rowDelta)
-      else
+      else if rowDelta < 0
         @lastRenderedScreenRow += rowDelta
         @updateVisibleLines()
 

src/app/renderer.coffee

@@ -37,7 +37,7 @@ class Renderer
     oldRange = @rangeForAllLines()
     @buildLineMap()
     newRange = @rangeForAllLines()
-    @trigger 'change', { oldRange, newRange }
+    @trigger 'change', { oldRange, newRange, lineNumbersChanged: true }
 
   lineForRow: (row) ->
     @lineMap.lineForScreenRow(row)
@@ -62,7 +62,7 @@ class Renderer
     @lineMap.replaceScreenRows(oldScreenRange.start.row, oldScreenRange.end.row, lines)
     newScreenRange = @screenLineRangeForBufferRange(bufferRange)
 
-    @trigger 'change', oldRange: oldScreenRange, newRange: newScreenRange
+    @trigger 'change', oldRange: oldScreenRange, newRange: newScreenRange, lineNumbersChanged: true
     @trigger 'fold', bufferRange
     fold
 
@@ -76,7 +76,7 @@ class Renderer
     @lineMap.replaceScreenRows(oldScreenRange.start.row, oldScreenRange.end.row, lines)
     newScreenRange = @screenLineRangeForBufferRange(bufferRange)
 
-    @trigger 'change', oldRange: oldScreenRange, newRange: newScreenRange
+    @trigger 'change', oldRange: oldScreenRange, newRange: newScreenRange, lineNumbersChanged: true
     @trigger 'unfold', bufferRange
 
   screenRowForBufferRow: (bufferRow) ->
@@ -111,16 +111,20 @@ class Renderer
     @handleHighlighterChange(@lastHighlighterChangeEvent)
 
   handleHighlighterChange: (e) ->
-    oldRange = @bufferRangeForScreenRange(@screenRangeForBufferRange(e.oldRange.copy()))
-    newRange = @bufferRangeForScreenRange(@screenRangeForBufferRange(e.newRange.copy()))
+    newRange = e.newRange.copy()
+    newRange.start.row = @bufferRowForScreenRow(@screenRowForBufferRow(newRange.start.row))
 
-    oldScreenRange = @screenLineRangeForBufferRange(oldRange)
+    oldScreenRange = @screenLineRangeForBufferRange(e.oldRange)
 
     newScreenLines = @buildLinesForBufferRows(newRange.start.row, newRange.end.row)
     @lineMap.replaceScreenRows oldScreenRange.start.row, oldScreenRange.end.row, newScreenLines
     newScreenRange = @screenLineRangeForBufferRange(newRange)
 
-    @trigger 'change', { oldRange: oldScreenRange, newRange: newScreenRange, bufferChanged: true }
+    @trigger 'change',
+      oldRange: oldScreenRange
+      newRange: newScreenRange
+      bufferChanged: true
+      lineNumbersChanged: !e.oldRange.coversSameRows(newRange) or !oldScreenRange.coversSameRows(newScreenRange)
 
   buildLineForBufferRow: (bufferRow) ->
     @buildLinesForBufferRows(bufferRow, bufferRow)