gitk: Fix direction of symmetric difference in optimized mode

ee66e08 (gitk: Make updates go faster, 2008-05-09) implemented an
optimized mode where gitk parses the arguments with rev-parse, and
manually reads history in chunks.  As mentioned in the commit message,
symmetric differences are a problem there:

    One wrinkle is that we have to turn symmetric diff arguments (of the
    form a...b) back into symmetric diff form so that --left-right still
    works, as git rev parse turns a...b into a b ^merge_base(a,b).

However, git-rev-parse returns a...b in the swapped order

    b a ^merge_base(a,b)

This has been the case since at least 1f8115b (the state of master at
the time of the abovementioned ee66e08; Merge branch 'maint',
2008-05-08).  So gitk flipped the sides of symmetric differences
whenever it was in optimized mode.

Fix this by swapping the sides of the reconstruction code.

Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Paul Mackerras <paulus@samba.org>

diff --git a/gitk b/gitk
index d0ab575d13facb6daabec973c8a86a6ccf16eb51..ef4ba3c98499b1a553eae7f605481746d601e828 100755 (executable)
--- a/gitk
+++ b/gitk
@@ -288,7 +288,7 @@ proc parseviewrevs {view revs} {
            if {$sdm != 2} {
                lappend ret $id
            } else {
-               lset ret end [lindex $ret end]...$id
+               lset ret end $id...[lindex $ret end]
            }
            lappend pos $id
        }