gitk's "Markup words" and "Color words" modes incorrectly display patches that contains angle brackets

[Nils Schimmelmann]

How to reproduce the bug, first create a patch with the following "git diff --word-diff=plain" diff.

    --- a/bug.txt
    +++ b/bug.txt
    @@ -1,2 +1,2 @@
    [-x-]{+z+} < 1
    [-y-]{+w+} > 2

Use gitk and switch into "Markup words" or "Color words" mode (e.g. "gitk --color-words -- bug.txt"), and then select one of the radio buttons. You will see:

  * "Diff" shows bogus removal on 1st line and bogus addition on 2nd line.
  * "Old version" cuts off at right angle bracket.
  * "New Version" cuts off at left angle bracket.