FoldSuggester can return a row range of a foldable syntactic region starting at a given row

spec/app/fold-suggester-spec.coffee

@@ -1,12 +1,14 @@
 FoldSuggester = require 'fold-suggester'
 Buffer = require 'buffer'
+Highlighter = require 'highlighter'
 
 describe "FoldSuggester", ->
   foldSuggester = null
 
   beforeEach ->
     buffer = new Buffer(require.resolve 'fixtures/sample.js')
-    foldSuggester = new FoldSuggester(buffer)
+    highlighter = new Highlighter(buffer)
+    foldSuggester = new FoldSuggester(highlighter)
 
   describe ".isBufferRowFoldable(bufferRow)", ->
     it "returns true only when the buffer row starts a foldable region", ->
@@ -14,3 +16,11 @@ describe "FoldSuggester", ->
       expect(foldSuggester.isBufferRowFoldable(1)).toBeTruthy()
       expect(foldSuggester.isBufferRowFoldable(2)).toBeFalsy()
       expect(foldSuggester.isBufferRowFoldable(3)).toBeFalsy()
+
+  describe ".rowRangeForFoldAtBufferRow(bufferRow)", ->
+    it "returns the start/end rows of the foldable region starting at the given row", ->
+      expect(foldSuggester.rowRangeForFoldAtBufferRow(0)).toEqual [1, 12]
+      expect(foldSuggester.rowRangeForFoldAtBufferRow(1)).toEqual [2, 9]
+      expect(foldSuggester.rowRangeForFoldAtBufferRow(2)).toBeNull()
+      expect(foldSuggester.rowRangeForFoldAtBufferRow(4)).toEqual [5, 7]
+

src/app/ace-fold-adaptor.coffee

@@ -1,6 +1,13 @@
 module.exports =
 class AceFoldAdaptor
-  constructor: (@buffer) ->
+  foldWidgets: {}
+
+  constructor: (@highlighter) ->
+    @buffer = @highlighter.buffer
 
   getLine: (bufferRow) ->
     @buffer.lineForRow(bufferRow)
+
+  $findClosingBracket: (bracketType, bufferPosition) ->
+    @highlighter.findClosingBracket([bufferPosition.row, bufferPosition.column - 1])
+

src/app/fold-suggester.coffee

@@ -2,9 +2,16 @@ AceFoldAdaptor = require 'ace-fold-adaptor'
 
 module.exports =
 class FoldSuggester
-  constructor: (@buffer) ->
+  constructor: (@highlighter) ->
+    @buffer = @highlighter.buffer
     @aceFoldMode = @buffer.getMode().foldingRules
-    @aceFoldAdaptor = new AceFoldAdaptor(@buffer)
+    @aceFoldAdaptor = new AceFoldAdaptor(@highlighter)
 
   isBufferRowFoldable: (bufferRow) ->
     @aceFoldMode?.getFoldWidget(@aceFoldAdaptor, null, bufferRow) == "start"
+
+  rowRangeForFoldAtBufferRow: (bufferRow) ->
+    if aceRange = @aceFoldMode?.getFoldWidgetRange(@aceFoldAdaptor, null, bufferRow)
+      [aceRange.start.row + 1, aceRange.end.row]
+    else
+      null