Handle the case of a parent being listed twice in a merge.

This happens in the linux-2.6 tree.  We draw the graph line
double-thick to show that this happened.

Also fix a bug where we got a bogus "No commit information available"
line at the end on simple repositories like this one.

diff --git a/gitk b/gitk
index f6c4ec2..d509998 100755 (executable)
--- a/gitk
+++ b/gitk
@@ -36,7 +36,7 @@ proc getcommits {rargs} {
 }
 
 proc getcommitline {commfd}  {
-    global commits parents cdate children nchildren ncleft
+    global commits parents cdate children nchildren
     global commitlisted phase commitinfo nextupdate
     global stopped redisplaying nlines
 
@@ -144,12 +144,11 @@ proc readcommit {id} {
                    }
                    lappend parents($id) $p
                    incr nparents($id)
+                   # sometimes we get a commit that lists a parent twice...
                    if {[lsearch -exact $children($p) $id] < 0} {
                        lappend children($p) $id
                        incr nchildren($p)
                        incr ncleft($p)
-                   } else {
-                       puts "child $id already in $p's list??"
                    }
                } elseif {$tag == "author"} {
                    set x [expr {[llength $line] - 2}]
@@ -591,12 +590,21 @@ proc initgraph {} {
     }
 }
 
+proc bindline {t id} {
+    global canv
+
+    $canv bind $t <Button-3> "linemenu %X %Y $id"
+    $canv bind $t <Enter> "lineenter %x %y $id"
+    $canv bind $t <Motion> "linemotion %x %y $id"
+    $canv bind $t <Leave> "lineleave $id"
+}
+
 proc drawcommitline {level} {
-    global parents children nparents nchildren ncleft todo
+    global parents children nparents nchildren todo
     global canv canv2 canv3 mainfont namefont canvx0 canvy linespc
     global datemode cdate
     global lineid linehtag linentag linedtag commitinfo
-    global colormap numcommits currentparents
+    global colormap numcommits currentparents dupparents
     global oldlevel oldnlines oldtodo
     global idtags idline idheads
     global lineno lthickness glines
@@ -616,8 +624,16 @@ proc drawcommitline {level} {
        }
     }
     set currentparents {}
+    set dupparents {}
     if {[info exists commitlisted($id)] && [info exists parents($id)]} {
-       set currentparents $parents($id)
+       foreach p $parents($id) {
+           if {[lsearch -exact $currentparents $p] < 0} {
+               lappend currentparents $p
+           } else {
+               # remember that this parent was listed twice
+               lappend dupparents $p
+           }
+       }
     }
     set x [expr $canvx0 + $level * $linespc]
     set y1 $canvy
@@ -629,10 +645,7 @@ proc drawcommitline {level} {
        set t [$canv create line $glines($id) \
                   -width $lthickness -fill $colormap($id)]
        $canv lower $t
-       $canv bind $t <Button-3> "linemenu %X %Y $id"
-       $canv bind $t <Enter> "lineenter %x %y $id"
-       $canv bind $t <Motion> "linemotion %x %y $id"
-       $canv bind $t <Leave> "lineleave $id"
+       bindline $t $id
     }
     set orad [expr {$linespc / 3}]
     set t [$canv create oval [expr $x - $orad] [expr $y1 - $orad] \
@@ -667,10 +680,6 @@ proc drawcommitline {level} {
        set t [$canv create line $x $y1 [lindex $xvals end] $y1 \
                   -width $lthickness -fill black]
        $canv lower $t
-       $canv bind $t <Button-3> "linemenu %X %Y $id"
-       $canv bind $t <Enter> "lineenter %x %y $id"
-       $canv bind $t <Motion> "linemotion %x %y $id"
-       $canv bind $t <Leave> "lineleave $id"
        foreach tag $marks x $xvals wid $wvals {
            set xl [expr $x + $delta]
            set xr [expr $x + $delta + $wid + $lthickness]
@@ -742,7 +751,7 @@ proc updatetodo {level noshortcut} {
 
 proc drawslants {} {
     global canv glines canvx0 canvy linespc
-    global oldlevel oldtodo todo currentparents
+    global oldlevel oldtodo todo currentparents dupparents
     global lthickness linespc canvy colormap
 
     set y1 [expr $canvy - $linespc]
@@ -755,27 +764,36 @@ proc drawslants {} {
        if {$i == $oldlevel} {
            foreach p $currentparents {
                set j [lsearch -exact $todo $p]
-               if {$i == $j && ![info exists glines($p)]} {
-                   set glines($p) [list $xi $y1]
-               } else {
-                   set xj [expr {$canvx0 + $j * $linespc}]
-                   set coords [list $xi $y1]
-                   if {$j < $i - 1} {
-                       lappend coords [expr $xj + $linespc] $y1
-                   } elseif {$j > $i + 1} {
-                       lappend coords [expr $xj - $linespc] $y1
-                   }
+               set coords [list $xi $y1]
+               set xj [expr {$canvx0 + $j * $linespc}]
+               if {$j < $i - 1} {
+                   lappend coords [expr $xj + $linespc] $y1
+               } elseif {$j > $i + 1} {
+                   lappend coords [expr $xj - $linespc] $y1
+               }
+               if {[lsearch -exact $dupparents $p] >= 0} {
+                   # draw a double-width line to indicate the doubled parent
                    lappend coords $xj $y2
+                   set t [$canv create line $coords \
+                              -width [expr 2*$lthickness] -fill $colormap($p)]
+                   $canv lower $t
+                   bindline $t $p
+                   if {![info exists glines($p)]} {
+                       set glines($p) [list $xj $y2]
+                   }
+               } else {
+                   # normal case, no parent duplicated
                    if {![info exists glines($p)]} {
+                       if {$i != $j} {
+                           lappend coords $xj $y2
+                       }
                        set glines($p) $coords
                    } else {
-                       set t [$canv create line $coords -width $lthickness \
-                                  -fill $colormap($p)]
+                       lappend coords $xj $y2
+                       set t [$canv create line $coords \
+                                  -width $lthickness -fill $colormap($p)]
                        $canv lower $t
-                       $canv bind $t <Button-3> "linemenu %X %Y $p"
-                       $canv bind $t <Enter> "lineenter %x %y $p"
-                       $canv bind $t <Motion> "linemotion %x %y $p"
-                       $canv bind $t <Leave> "lineleave $p"
+                       bindline $t $p
                    }
                }
            }
@@ -929,34 +947,36 @@ proc drawrest {level startix} {
     global numcommits
     global nextupdate startmsecs startcommits idline
 
-    set phase drawgraph
-    set startid [lindex $startcommits $startix]
-    set startline -1
-    if {$startid != {}} {
-       set startline $idline($startid)
-    }
-    while 1 {
-       if {$stopped} break
-       drawcommitline $level
-       set hard [updatetodo $level $datemode]
-       if {$numcommits == $startline} {
-           lappend todo $startid
-           set hard 1
-           incr startix
-           set startid [lindex $startcommits $startix]
-           set startline -1
-           if {$startid != {}} {
-               set startline $idline($startid)
-           }
-       }
-       if {$hard} {
-           set level [decidenext]
-           if {$level < 0} break
-           drawslants
+    if {$level >= 0} {
+       set phase drawgraph
+       set startid [lindex $startcommits $startix]
+       set startline -1
+       if {$startid != {}} {
+           set startline $idline($startid)
        }
-       if {[clock clicks -milliseconds] >= $nextupdate} {
-           update
-           incr nextupdate 100
+       while 1 {
+           if {$stopped} break
+           drawcommitline $level
+           set hard [updatetodo $level $datemode]
+           if {$numcommits == $startline} {
+               lappend todo $startid
+               set hard 1
+               incr startix
+               set startid [lindex $startcommits $startix]
+               set startline -1
+               if {$startid != {}} {
+                   set startline $idline($startid)
+               }
+           }
+           if {$hard} {
+               set level [decidenext]
+               if {$level < 0} break
+               drawslants
+           }
+           if {[clock clicks -milliseconds] >= $nextupdate} {
+               update
+               incr nextupdate 100
+           }
        }
     }
     set phase {}