optimize whitespace dedup

diff --git a/editor.coffee b/editor.coffee
index a0bd0a4..dd39c62 100644 (file)
--- a/editor.coffee
+++ b/editor.coffee
@@ -559,21 +559,32 @@ tree_dedup_space = (tree) ->
                                        throw "how is this possible?"
                                next_i -= 1
                        return 1
                                        throw "how is this possible?"
                                next_i -= 1
                        return 1

-       whitespace_to_space = (undo) ->
+       replace_with_space = (undo) ->

                if undo
                        cur.text = (cur.text.substr 0, cur_i) + removed_char + (cur.text.substr cur_i + 1)
                        cur.el.textContent = cur.text
                else
                        removed_char = cur.text.charAt(cur_i)
                if undo
                        cur.text = (cur.text.substr 0, cur_i) + removed_char + (cur.text.substr cur_i + 1)
                        cur.el.textContent = cur.text
                else
                        removed_char = cur.text.charAt(cur_i)

-                       cur.text = (cur.text.substr 0, cur_i) + ' ' + (cur.text.substr cur_i + 1)
-                       cur.el.textContent = cur.text
+                       if removed_char isnt ' '
+                               cur.text = (cur.text.substr 0, cur_i) + ' ' + (cur.text.substr cur_i + 1)
+                               cur.el.textContent = cur.text

                return 0
        # return true if cur was removed from the dom (ie re-use same prev)
        operate = ->
                # cur definitately set
                # prev and/or next might be null, indicating the start/end of a display:block
                return false unless is_space_code cur.text.charCodeAt cur_i
                return 0
        # return true if cur was removed from the dom (ie re-use same prev)
        operate = ->
                # cur definitately set
                # prev and/or next might be null, indicating the start/end of a display:block
                return false unless is_space_code cur.text.charCodeAt cur_i

-               fixers = [remove, whitespace_to_space]
+               fixers = [remove, replace_with_space]
+               # check for common case: single whitespace surrounded by non-whitespace chars
+               if prev? and next?
+                       unless (is_space_code prev.text.charCodeAt prev_i) or (is_space_code next.text.charCodeAt next_i)
+                               dbg = cur.text.charCodeAt cur_i
+                               if cur.text.charAt(cur_i) is ' ' # perens required
+                                       # single space can't collapse, doesn't need fixin'
+                                       return false
+                               else
+                                       # tab, newline, etc, can't collapse, but maybe should be replaced
+                                       fixers = [replace_with_space]

                bounds = text_range_bounds cur.el, cur_i, cur_i + 1
                # consistent cases:
                # 1. zero rects returned by getClientRects() means collapsed space
                bounds = text_range_bounds cur.el, cur_i, cur_i + 1
                # consistent cases:
                # 1. zero rects returned by getClientRects() means collapsed space

@@ -581,7 +592,8 @@ tree_dedup_space = (tree) ->
                        return remove()
                # 2. width greater than zero means visible space
                if bounds.w > 0
                        return remove()
                # 2. width greater than zero means visible space
                if bounds.w > 0

-                       fixers.shift() # don't try removing
+                       # has bounds, don't try removing
+                       fixers = [replace_with_space]

                # now the weird edge cases...
                #
                # firefox and chromium both report zero width for characters at the end
                # now the weird edge cases...
                #
                # firefox and chromium both report zero width for characters at the end

@@ -590,6 +602,11 @@ tree_dedup_space = (tree) ->
                # collapsed spaces via the range/bounds api, so...
                #
                # remove it from the dom, and if prev or next moves, put it back.
                # collapsed spaces via the range/bounds api, so...
                #
                # remove it from the dom, and if prev or next moves, put it back.

+               #
+               # this block (try changing it, put it back if something moves) is also
+               # used on collapsable whitespace characters besides space. In this case
+               # the character is replaced with a normal space character instead of
+               # removed

                if prev? and not prev_px?
                        prev_px = new_cursor_position n: prev, i: prev_i
                if next? and not next_px?
                if prev? and not prev_px?
                        prev_px = new_cursor_position n: prev, i: prev_i
                if next? and not next_px?