When folds are selected they are highlighted

spec/app/editor-spec.coffee

@@ -2460,6 +2460,39 @@ describe "Editor", ->
 
         expect(editor.getCursorBufferPosition()).toEqual [3, 0]
 
+    describe "when a selection starts/stops intersecting a fold", ->
+      it "adds/removes the 'selected' class to the fold's line element", ->
+        editor.createFold(2, 4)
+
+        editor.setSelectionBufferRange([[1, 0], [2, 0]], reverse: true)
+        expect(editor.lineElementForScreenRow(2)).toMatchSelector('.fold.selected')
+
+        editor.setSelectionBufferRange([[1, 0], [1, 1]])
+        expect(editor.lineElementForScreenRow(2)).not.toMatchSelector('.fold.selected')
+
+        editor.setSelectionBufferRange([[1, 0], [5, 0]])
+        expect(editor.lineElementForScreenRow(2)).toMatchSelector('.fold.selected')
+
+        editor.setCursorScreenPosition([3,0])
+        expect(editor.lineElementForScreenRow(2)).not.toMatchSelector('.fold.selected')
+
+        editor.setCursorScreenPosition([2,0])
+        expect(editor.lineElementForScreenRow(2)).toMatchSelector('.fold.selected')
+
+    describe "when a selected fold is scrolled into view (and the fold line was not previously rendered)", ->
+      it "renders the fold's line element with the 'selected' class", ->
+        setEditorHeightInLines(editor, 5)
+
+        editor.createFold(2, 4)
+        editor.setSelectionBufferRange([[1, 0], [5, 0]])
+        expect(editor.visibleLines.find('.fold.selected')).toExist()
+
+        editor.scrollToBottom()
+        expect(editor.visibleLines.find('.fold.selected')).not.toExist()
+
+        editor.scrollTop(0)
+        expect(editor.lineElementForScreenRow(2)).toMatchSelector('.fold.selected')
+
   describe "editor-path-change event", ->
     it "emits event when buffer's path is changed", ->
       editor = new Editor

src/app/composite-selection.coffee

@@ -74,6 +74,10 @@ class CompositeSeleciton
   getText: ->
     @getLastSelection().getText()
 
+  intersectsBufferRange: (bufferRange) ->
+    _.any @getSelections(), (selection) ->
+      selection.intersectsBufferRange(bufferRange)
+
   expandSelectionsForward: (fn) ->
     fn(selection) for selection in @getSelections()
     @mergeIntersectingSelections()

src/app/editor.coffee

@@ -62,6 +62,7 @@ class Editor extends View
     requireStylesheet 'theme/twilight.css'
 
     @id = Editor.idCounter++
+    @lineCache = []
     @bindKeys()
     @autoIndent = true
     @buildCursorAndSelection()
@@ -335,13 +336,25 @@ class Editor extends View
   getLastVisibleScreenRow: ->
     Math.ceil((@scrollTop() + @scrollView.height()) / @lineHeight) - 1
 
+  highlightSelectedFolds: ->
+    screenLines = @screenLinesForRows(@firstRenderedScreenRow, @lastRenderedScreenRow)
+    for screenLine, i in screenLines
+      if fold = screenLine.fold
+        screenRow = @firstRenderedScreenRow + i
+        element = @lineElementForScreenRow(screenRow)
+        if @compositeSelection.intersectsBufferRange(fold.getBufferRange())
+          
+          element.addClass('selected')
+        else
+          element.removeClass('selected')
+
   getScreenLines: ->
     @renderer.getLines()
 
   screenLineForRow: (start) ->
     @renderer.lineForRow(start)
 
-  linesForRows: (start, end) ->
+  screenLinesForRows: (start, end) ->
     @renderer.linesForRows(start, end)
 
   screenLineCount: ->
@@ -468,11 +481,14 @@ class Editor extends View
     charWidth = @charWidth
     charHeight = @charHeight
     lines = @renderer.linesForRows(startRow, endRow)
+    compositeSelection = @compositeSelection
 
     $$ ->
       for line in lines
         if fold = line.fold
           lineAttributes = { class: 'fold line', 'fold-id': fold.id }
+          if compositeSelection.intersectsBufferRange(fold.getBufferRange())
+            lineAttributes.class += ' selected'
         else
           lineAttributes = { class: 'line' }
         @div lineAttributes, =>
@@ -514,8 +530,9 @@ class Editor extends View
     elementsToReplace.forEach (element) =>
       lines.removeChild(element)
 
-  getLineElement: (row) ->
-    @lineCache[row]
+  lineElementForScreenRow: (screenRow) ->
+    element = @lineCache[screenRow - @firstRenderedScreenRow]
+    $(element)
 
   toggleSoftWrap: ->
     @setSoftWrap(not @softWrap)
@@ -747,6 +764,9 @@ class Editor extends View
     @scrollVertically(pixelPosition)
     @scrollHorizontally(pixelPosition)
 
+  scrollToBottom: ->
+    @scrollBottom(@scrollView.prop('scrollHeight'))
+
   scrollVertically: (pixelPosition) ->
     linesInView = @scrollView.height() / @lineHeight
     maxScrollMargin = Math.floor((linesInView - 1) / 2)

src/app/fold.coffee

@@ -18,6 +18,9 @@ class Fold
   inspect: ->
     "Fold(#{@startRow}, #{@endRow})"
 
+  getBufferRange: ->
+    new Range([@startRow, 0], [@endRow, Infinity])
+
   getBufferDelta: ->
     new Point(@endRow - @startRow + 1, 0)
 

src/app/selection.coffee

@@ -45,6 +45,8 @@ class Selection extends View
     @clearRegions()
 
     range = @getScreenRange()
+
+    @editor.highlightSelectedFolds()
     return if range.isEmpty()
 
     rowSpan = range.end.row - range.start.row
@@ -57,6 +59,7 @@ class Selection extends View
         @appendRegion(rowSpan - 1, { row: range.start.row + 1, column: 0}, null)
       @appendRegion(1, { row: range.end.row, column: 0 }, range.end)
 
+
   appendRegion: (rows, start, end) ->
     { lineHeight, charWidth } = @editor
     css = @editor.pixelPositionForScreenPosition(start)
@@ -80,8 +83,7 @@ class Selection extends View
     else
       new Range(@cursor.getScreenPosition(), @cursor.getScreenPosition())
 
-  setScreenRange: (range, options={}) ->
-    { reverse } = options
+  setScreenRange: (range, {reverse}={}) ->
     { start, end } = range
     [start, end] = [end, start] if reverse
 
@@ -97,6 +99,9 @@ class Selection extends View
   getText: ->
     @editor.buffer.getTextInRange @getBufferRange()
 
+  intersectsBufferRange: (bufferRange) ->
+    @getBufferRange().intersectsWith(bufferRange)
+
   insertText: (text) ->
     { text, shouldOutdent } = @autoIndentText(text)
     oldBufferRange = @getBufferRange()

static/theme/twilight.css

@@ -74,6 +74,11 @@ color:#D2A8A1;
   color: #969696;
 }
 
+.fold.selected {
+  background-color: #82715C;
+  color: #969696;
+}
+
 .support.function {
   color:#DAD085;
 }