Start on rough version of LineFolder.screenPositionForBufferPosition

Still pretty ugly and not working quite right.

spec/atom/line-folder-spec.coffee

@@ -11,44 +11,68 @@ describe "LineFolder", ->
     highlighter = new Higlighter(buffer)
     folder = new LineFolder(highlighter)
 
-  describe "when there is a single fold spanning multiple lines", ->
-    it "renders a placeholder on the first line of a fold, and skips subsequent lines", ->
-      folder.createFold(new Range([4, 29], [7, 4]))
-      [line4, line5] = folder.screenLinesForRows(4, 5)
-
-      expect(line4.text).toBe '    while(items.length > 0) {...}'
-      expect(line5.text).toBe '    return sort(left).concat(pivot).concat(sort(right));'
-
-  describe "when there is a single fold contained on a single line", ->
-    it "renders a placeholder for the folded region, but does not skip any lines", ->
-      folder.createFold(new Range([2, 8], [2, 25]))
-      [line2, line3] = folder.screenLinesForRows(2, 3)
-
-      expect(line2.text).toBe '    if (...) return items;'
-      expect(line3.text).toBe '    var pivot = items.shift(), current, left = [], right = [];'
-
-  describe "when there is a nested fold on the last line of another fold", ->
-    it "does not render a placeholder for the nested fold because it is inside of the other fold", ->
-      folder.createFold(new Range([8, 5], [8, 10]))
-      folder.createFold(new Range([4, 29], [8, 36]))
-      [line4, line5] = folder.screenLinesForRows(4, 5)
-
-      expect(line4.text).toBe '    while(items.length > 0) {...concat(sort(right));'
-      expect(line5.text).toBe '  };'
-
-  describe "when another fold begins on the last line of a fold", ->
-    describe "when the second fold is created before the first fold", ->
-      it "renders a placeholder for both folds on the first line of the first fold", ->
-        folder.createFold(new Range([7, 5], [8, 36]))
+  describe "screen line rendering", ->
+    describe "when there is a single fold spanning multiple lines", ->
+      it "renders a placeholder on the first line of a fold, and skips subsequent lines", ->
         folder.createFold(new Range([4, 29], [7, 4]))
         [line4, line5] = folder.screenLinesForRows(4, 5)
 
-        expect(line4.text).toBe  '    while(items.length > 0) {...}...concat(sort(right));'
+        expect(line4.text).toBe '    while(items.length > 0) {...}'
+        expect(line5.text).toBe '    return sort(left).concat(pivot).concat(sort(right));'
 
-    describe "when the second fold is created after the first fold", ->
-      it "renders a placeholder for both folds on the first line of the first fold", ->
-        folder.createFold(new Range([4, 29], [7, 4]))
-        folder.createFold(new Range([7, 5], [8, 36]))
+    describe "when there is a single fold contained on a single line", ->
+      it "renders a placeholder for the folded region, but does not skip any lines", ->
+        folder.createFold(new Range([2, 8], [2, 25]))
+        [line2, line3] = folder.screenLinesForRows(2, 3)
+
+        expect(line2.text).toBe '    if (...) return items;'
+        expect(line3.text).toBe '    var pivot = items.shift(), current, left = [], right = [];'
+
+    describe "when there is a nested fold on the last line of another fold", ->
+      it "does not render a placeholder for the nested fold because it is inside of the other fold", ->
+        folder.createFold(new Range([8, 5], [8, 10]))
+        folder.createFold(new Range([4, 29], [8, 36]))
         [line4, line5] = folder.screenLinesForRows(4, 5)
 
-        expect(line4.text).toBe  '    while(items.length > 0) {...}...concat(sort(right));'
+        expect(line4.text).toBe '    while(items.length > 0) {...concat(sort(right));'
+        expect(line5.text).toBe '  };'
+
+    describe "when another fold begins on the last line of a fold", ->
+      describe "when the second fold is created before the first fold", ->
+        it "renders a placeholder for both folds on the first line of the first fold", ->
+          folder.createFold(new Range([7, 5], [8, 36]))
+          folder.createFold(new Range([4, 29], [7, 4]))
+          [line4, line5] = folder.screenLinesForRows(4, 5)
+
+          expect(line4.text).toBe  '    while(items.length > 0) {...}...concat(sort(right));'
+
+      describe "when the second fold is created after the first fold", ->
+        it "renders a placeholder for both folds on the first line of the first fold", ->
+          folder.createFold(new Range([4, 29], [7, 4]))
+          folder.createFold(new Range([7, 5], [8, 36]))
+          [line4, line5] = folder.screenLinesForRows(4, 5)
+
+          expect(line4.text).toBe  '    while(items.length > 0) {...}...concat(sort(right));'
+
+  fdescribe ".screenPositionForBufferPosition(bufferPosition)", ->
+    describe "when there is single fold spanning multiple lines", ->
+      it "translates positions to account for folded lines and characters and the placeholder", ->
+        folder.createFold(new Range([4, 29], [7, 4]))
+
+        # preceding fold: identity
+        expect(folder.screenPositionForBufferPosition([3, 0])).toEqual [3, 0]
+        expect(folder.screenPositionForBufferPosition([4, 0])).toEqual [4, 0]
+        expect(folder.screenPositionForBufferPosition([4, 29])).toEqual [4, 29]
+
+        # inside of fold: translate to the start of the fold
+        # expect(folder.screenPositionForBufferPosition([4, 30])).toEqual [4, 29]
+        # expect(folder.screenPositionForBufferPosition([5, 5])).toEqual [4, 29]
+
+        # following fold, on last line of fold
+        expect(folder.screenPositionForBufferPosition([7, 4])).toEqual [4, 32]
+        expect(folder.screenPositionForBufferPosition([7, 7])).toEqual [4, 35]
+
+        # # following fold, subsequent line
+        expect(folder.screenPositionForBufferPosition([8, 0])).toEqual [5, 0]
+        expect(folder.screenPositionForBufferPosition([13, 13])).toEqual [10, 13]
+

src/atom/line-folder.coffee

@@ -1,4 +1,5 @@
 SpanIndex = require 'span-index'
+Point = require 'point'
 
 module.exports =
 class LineFolder
@@ -44,6 +45,31 @@ class LineFolder
   bufferRowForScreenRow: (screenRow) ->
     @index.indexForSpan(screenRow).index
 
+  screenPositionForBufferPosition: (bufferPosition) ->
+    bufferPosition = Point.fromObject(bufferPosition)
+    screenRow = 0
+    screenColumn = 0
+    bufferRow = 0
+
+    while bufferRow < bufferPosition.row
+      console.log "HI", bufferRow, screenColumn
+      if fold = @maximalFoldStartingAtBufferRow(bufferRow)
+        bufferRow = fold.range.end.row
+        screenColumn += fold.range.start.column + 3 + bufferPosition.column - fold.range.end.column
+      else
+        bufferRow++
+        screenRow++
+        if bufferRow == bufferPosition.row
+          screenColumn = bufferPosition.column
+        else
+          screenColumn = 0
+
+    new Point(screenRow, screenColumn)
+
+  maximalFoldStartingAtBufferRow: (bufferRow) ->
+    @activeFolds[bufferRow]
+
+
 class Fold
   constructor: (@lineFolder, @range) ->
     @lineFolder.activeFolds[@range.start.row] = this