Visual/edit modes: better reverseSelection().

There's an efficient way to implement reverseSelection, and an
inefficient way.  Unfortunately, the efficient way does not work for
text inputs like textareas.  So we fall back to the inefficient method
in that case.

1 files changed, 22 insertions, 9 deletions

diff --git a/content_scripts/mode_visual_edit.coffee b/content_scripts/mode_visual_edit.coffee
index 261166f9..6f327807 100644
--- a/content_scripts/mode_visual_edit.coffee
+++ b/content_scripts/mode_visual_edit.coffee
@@ -73,6 +73,27 @@ class Movement extends MaintainCount
     chrome.runtime.sendMessage handler: "pasteFromClipboard", (response) ->
       callback response
 
+  # Swap the anchor node/offset and the focus node/offset.
+  reverseSelection: ->
+    element = document.activeElement
+    if element and DomUtils.isEditable(element) and not element. isContentEditable
+      # Note(smblott). This implementation is unacceptably inefficient if the selection is large.  We only use
+      # it if we have to.  However, the normal method does not work for input elements.
+      direction = @getDirection()
+      length = @selection.toString().length
+      @selection[if direction == forward then "collapseToEnd" else "collapseToStart"]()
+      @selection.modify "extend", @opposite[direction], character for [0...length]
+    else
+      # Normal method.
+      direction = @getDirection()
+      original = @selection.getRangeAt(0).cloneRange()
+      range = original.cloneRange()
+      range.collapse direction == backward
+      @selection.removeAllRanges()
+      @selection.addRange range
+      which = if direction == forward then "start" else "end"
+      @selection.extend original["#{which}Container"], original["#{which}Offset"],
+
   # Run a movement command.
   runMovement: (movement) ->
     @selection.modify @alterMethod, movement.split(" ")...
@@ -105,14 +126,6 @@ class Movement extends MaintainCount
     movements = [ "forward word", "forward word", "backward word" ]
     @runMovement movement for movement in movements
 
-  # Swap the focus and anchor.
-  # FIXME(smblott). This implementation is rediculously inefficient if the selection is large.
-  reverseSelection: ->
-    direction = @getDirection()
-    length = @selection.toString().length
-    @selection[if direction == forward then "collapseToEnd" else "collapseToStart"]()
-    @selection.modify "extend", @opposite[direction], character for [0...length]
-
   movements:
     "l": "forward character"
     "h": "backward character"
@@ -322,7 +335,7 @@ class VisualMode extends Movement
 class VisualLineMode extends VisualMode
   constructor: (options = {}) ->
     super options
-    @selectLine()
+    @selectLine() unless @selection?.type == "None"
 
   handleMovementKeyChar: (keyChar) ->
     super keyChar