gitk: Add a progress bar to show progress while resetting

Since git reset now gets chatty while resetting, we were getting errors
reported when a reset was done using the "reset branch to here" menu
item.  With this we now read the progress messages from git reset and
update a progress bar.  Because git reset outputs the progress messages
to standard error, and Tcl treats messages to standard error as error
messages, we have to invoke git reset via a shell and redirect standard
error into standard output.

This also fixes a bug in computing descendent heads when head ids
are changed via a reset.

Signed-off-by: Paul Mackerras <paulus@samba.org>

diff --git a/gitk b/gitk
index 72a914590c03ca24673bb61ffebebfe6d447848f..269f9b08a0691b4741f85b714191998006513756 100755 (executable)
--- a/gitk
+++ b/gitk
@@ -5851,19 +5851,54 @@ proc resethead {} {
     bind $w <Visibility> "grab $w; focus $w"
     tkwait window $w
     if {!$confirm_ok} return
-    dohidelocalchanges
-    if {[catch {exec git reset --$resettype $rowmenuid} err]} {
+    if {[catch {set fd [open \
+           [list | sh -c "git reset --$resettype $rowmenuid 2>&1"] r]} err]} {
        error_popup $err
     } else {
-       set oldhead $mainheadid
-       movedhead $rowmenuid $mainhead
-       set mainheadid $rowmenuid
+       dohidelocalchanges
+       set w ".resetprogress"
+       filerun $fd [list readresetstat $fd $w]
+       toplevel $w
+       wm transient $w
+       wm title $w "Reset progress"
+       message $w.m -text "Reset in progress, please wait..." \
+           -justify center -aspect 1000
+       pack $w.m -side top -fill x -padx 20 -pady 5
+       canvas $w.c -width 150 -height 20 -bg white
+       $w.c create rect 0 0 0 20 -fill green -tags rect
+       pack $w.c -side top -fill x -padx 20 -pady 5 -expand 1
+       nowbusy reset
+    }
+}
+
+proc readresetstat {fd w} {
+    global mainhead mainheadid showlocalchanges
+
+    if {[gets $fd line] >= 0} {
+       if {[regexp {([0-9]+)% \(([0-9]+)/([0-9]+)\)} $line match p m n]} {
+           set x [expr {($m * 150) / $n}]
+           $w.c coords rect 0 0 $x 20
+       }
+       return 1
+    }
+    destroy $w
+    notbusy reset
+    if {[catch {close $fd} err]} {
+       error_popup $err
+    }
+    set oldhead $mainheadid
+    set newhead [exec git rev-parse HEAD]
+    if {$newhead ne $oldhead} {
+       movehead $newhead $mainhead
+       movedhead $newhead $mainhead
+       set mainheadid $newhead
        redrawtags $oldhead
-       redrawtags $rowmenuid
+       redrawtags $newhead
     }
     if {$showlocalchanges} {
        doshowlocalchanges
     }
+    return 0
 }
 
 # context menu for a head
@@ -6742,7 +6777,10 @@ proc descheads {id} {
            }
            foreach a $arcnos($id) {
                if {$archeads($a) ne {}} {
-                   set ret [concat $ret $archeads($a)]
+                   validate_archeads $a
+                   if {$archeads($a) ne {}} {
+                       set ret [concat $ret $archeads($a)]
+                   }
                }
                set d $arcstart($a)
                if {![info exists seen($d)]} {