Implement ::screenPositionForPixelPosition in LinesYardstick

src/lines-yardstick.coffee

@@ -12,6 +12,58 @@ class LinesYardstick
     @presenter.setScreenRowsToMeasure(screenRows)
     @lineNodesProvider.updateSync(@presenter.getPreMeasurementState())
 
+  screenPositionForPixelPosition: (pixelPosition) ->
+    targetTop = pixelPosition.top
+    targetLeft = pixelPosition.left
+    defaultCharWidth = @model.getDefaultCharWidth()
+    row = Math.floor(targetTop / @model.getLineHeightInPixels())
+    targetLeft = 0 if row < 0
+    targetLeft = Infinity if row > @model.getLastScreenRow()
+    row = Math.min(row, @model.getLastScreenRow())
+    row = Math.max(0, row)
+
+    tokenizedLine = @model.tokenizedLineForScreenRow(row)
+    lineNode = @lineNodesProvider.lineNodeForLineIdAndScreenRow(tokenizedLine.id, row)
+
+    return new Point(row, 0) unless lineNode? and tokenizedLine?
+
+    iterator = document.createNodeIterator(lineNode, NodeFilter.SHOW_TEXT, AcceptFilter)
+    charIndex = 0
+
+    @tokenIterator.reset(tokenizedLine)
+    while @tokenIterator.next()
+      text = @tokenIterator.getText()
+      textIndex = 0
+      while textIndex < text.length
+        if @tokenIterator.isPairedCharacter()
+          char = text
+          charLength = 2
+          textIndex += 2
+        else
+          char = text[textIndex]
+          charLength = 1
+          textIndex++
+
+        unless textNode?
+          textNode = iterator.nextNode()
+          textNodeLength = textNode.textContent.length
+          textNodeIndex = 0
+          nextTextNodeIndex = textNodeLength
+
+        while nextTextNodeIndex <= charIndex
+          textNode = iterator.nextNode()
+          textNodeLength = textNode.textContent.length
+          textNodeIndex = nextTextNodeIndex
+          nextTextNodeIndex = textNodeIndex + textNodeLength
+
+        indexWithinTextNode = charIndex - textNodeIndex
+        left = @leftPixelPositionForCharInTextNode(lineNode, textNode, indexWithinTextNode)
+        break if left >= targetLeft
+
+        charIndex += charLength
+
+    new Point(row, charIndex)
+
   pixelPositionForScreenPosition: (screenPosition, clip=true) ->
     screenPosition = Point.fromObject(screenPosition)
     screenPosition = @model.clipScreenPosition(screenPosition) if clip

src/text-editor-component.coffee

@@ -427,7 +427,7 @@ class TextEditorComponent
     position
 
   screenPositionForPixelPosition: (pixelPosition) ->
-    @presenter.screenPositionForPixelPosition(pixelPosition)
+    @linesYardstick.screenPositionForPixelPosition(pixelPosition)
 
   pixelRectForScreenRange: (screenRange) ->
     rect = @presenter.pixelRectForScreenRange(screenRange)
@@ -857,7 +857,7 @@ class TextEditorComponent
 
   screenPositionForMouseEvent: (event, linesClientRect) ->
     pixelPosition = @pixelPositionForMouseEvent(event, linesClientRect)
-    @presenter.screenPositionForPixelPosition(pixelPosition)
+    @screenPositionForPixelPosition(pixelPosition)
 
   pixelPositionForMouseEvent: (event, linesClientRect) ->
     {clientX, clientY} = event

src/text-editor-presenter.coffee

@@ -1626,38 +1626,3 @@ class TextEditorPresenter
 
   getVisibleRowRange: ->
     [@startRow, @endRow]
-
-  screenPositionForPixelPosition: (pixelPosition) ->
-    targetTop = pixelPosition.top
-    targetLeft = pixelPosition.left
-    defaultCharWidth = @baseCharacterWidth
-    row = Math.floor(targetTop / @lineHeight)
-    targetLeft = 0 if row < 0
-    targetLeft = Infinity if row > @model.getLastScreenRow()
-    row = Math.min(row, @model.getLastScreenRow())
-    row = Math.max(0, row)
-
-    left = 0
-    column = 0
-
-    iterator = @model.tokenizedLineForScreenRow(row).getTokenIterator()
-    while iterator.next()
-      charWidths = @getScopedCharacterWidths(iterator.getScopes())
-      value = iterator.getText()
-      valueIndex = 0
-      while valueIndex < value.length
-        if iterator.isPairedCharacter()
-          char = value
-          charLength = 2
-          valueIndex += 2
-        else
-          char = value[valueIndex]
-          charLength = 1
-          valueIndex++
-
-        charWidth = charWidths[char] ? defaultCharWidth
-        break if targetLeft <= left + (charWidth / 2)
-        left += charWidth
-        column += charLength
-
-    new Point(row, column)