When DisplayBuffer.foldBufferRow is called with a buffer row that is within a fold, it folds the scope that incloses the buffer row's fold

spec/app/display-buffer-spec.coffee

@@ -194,6 +194,15 @@ describe "DisplayBuffer", ->
           expect(fold.startRow).toBe 1
           expect(fold.endRow).toBe 9
 
+      describe "when the bufferRow is already folded", ->
+        it "searches upward for the first row that begins a syntatic region containing the folded row (and folds it)", ->
+          displayBuffer.foldBufferRow(2)
+          expect(displayBuffer.lineForRow(1).fold).toBeDefined()
+          expect(displayBuffer.lineForRow(0).fold).not.toBeDefined()
+
+          displayBuffer.foldBufferRow(1)
+          expect(displayBuffer.lineForRow(0).fold).toBeDefined()
+
    describe ".unfoldBufferRow(bufferRow)", ->
       describe "when bufferRow can be unfolded", ->
         it "destroys a fold based on the syntactic region starting at the given row", ->

src/app/display-buffer.coffee

@@ -61,18 +61,14 @@ class DisplayBuffer
       [startRow, endRow] = @tokenizedBuffer.rowRangeForFoldAtBufferRow(currentRow) ? []
       continue unless startRow? and startRow <= bufferRow <= endRow
       fold = @largestFoldStartingAtBufferRow(startRow)
-      @createFold(startRow, endRow) unless fold
+      continue if fold
+
+      @createFold(startRow, endRow)
 
       return
 
   unfoldBufferRow: (bufferRow) ->
-    for currentRow in [bufferRow..0]
-      [startRow, endRow] = @tokenizedBuffer.rowRangeForFoldAtBufferRow(currentRow) ? []
-      continue unless startRow? and startRow <= bufferRow <= endRow
-      fold = @largestFoldStartingAtBufferRow(startRow)
-      fold.destroy() if fold
-
-      return
+    @largestFoldContainingBufferRow(bufferRow)?.destroy()
 
   createFold: (startRow, endRow) ->
     return fold if fold = @foldFor(startRow, endRow)