git-gui: fix ANSI-color parsing

git diff always outputs color reset commands, even when the color for the
current part is disabled (ie. normal). But the current ANSI-color parsing code
assumes that color start and reset commands appear in matching pairs.

Relax this assumption.

Signed-off-by: Bert Wesarg <bert.wesarg@googlemail.com>
Signed-off-by: Pat Thoyts <patthoyts@users.sourceforge.net>

diff --git a/lib/diff.tcl b/lib/diff.tcl
index dcf0711be0119a8f5ec42b48d97980330f7113b3..0579fa609d191d5dc5244e1f56a3df9daaff9aa3 100644 (file)
--- a/lib/diff.tcl
+++ b/lib/diff.tcl
@@ -337,12 +337,20 @@ proc parse_color_line {line} {
        set result ""
        set markup [list]
        set regexp {\033\[((?:\d+;)*\d+)?m}
+       set need_reset 0
        while {[regexp -indices -start $start $regexp $line match code]} {
                foreach {begin end} $match break
                append result [string range $line $start [expr {$begin - 1}]]
-               lappend markup [string length $result] \
-                       [eval [linsert $code 0 string range $line]]
+               set pos [string length $result]
+               set col [eval [linsert $code 0 string range $line]]
                set start [incr end]
+               if {$col eq "0" || $col eq ""} {
+                       if {!$need_reset} continue
+                       set need_reset 0
+               } else {
+                       set need_reset 1
+               }
+               lappend markup $pos $col
        }
        append result [string range $line $start end]
        if {[llength $markup] < 4} {set markup {}}