gitk: Fix a couple more bugs in the path limiting

First, paths ending in a slash were not matching anything.  This fixes
path_filter to handle paths ending in a slash (such entries have to
match a directory, and can't match a file, e.g., foo/bar/ can't match
a plain file called foo/bar).

Secondly, clicking in the file list pane (bottom right) was broken
because $treediffs($ids) contained all the files modified by the
commit, not just those within the file list.  This fixes that too.
Signed-off-by: NPaul Mackerras <paulus@samba.org>

gitk

@@ -5023,28 +5023,25 @@ proc startdiff {ids} {
 proc path_filter {filter name} {
     foreach p $filter {
 	set l [string length $p]
-	if {[string compare -length $l $p $name] == 0 &&
-	    ([string length $name] == $l || [string index $name $l] eq "/")} {
-	    return 1
+	if {[string index $p end] eq "/"} {
+	    if {[string compare -length $l $p $name] == 0} {
+		return 1
+	    }
+	} else {
+	    if {[string compare -length $l $p $name] == 0 &&
+		([string length $name] == $l ||
+		 [string index $name $l] eq "/")} {
+		return 1
+	    }
 	}
     }
     return 0
 }
 
 proc addtocflist {ids} {
-    global treediffs cflist viewfiles curview limitdiffs
+    global treediffs
 
-    if {$limitdiffs && $viewfiles($curview) ne {}} {
-	set flist {}
-	foreach f $treediffs($ids) {
-	    if {[path_filter $viewfiles($curview) $f]} {
-		lappend flist $f
-	    }
-	}
-    } else {
-	set flist $treediffs($ids)
-    }
-    add_flist $flist
+    add_flist $treediffs($ids)
     getblobdiffs $ids
 }
 
@@ -5100,7 +5097,7 @@ proc gettreediffs {ids} {
 
 proc gettreediffline {gdtf ids} {
     global treediff treediffs treepending diffids diffmergeid
-    global cmitmode
+    global cmitmode viewfiles curview limitdiffs
 
     set nr 0
     while {[incr nr] <= 1000 && [gets $gdtf line] >= 0} {
@@ -5117,7 +5114,17 @@ proc gettreediffline {gdtf ids} {
 	return [expr {$nr >= 1000? 2: 1}]
     }
     close $gdtf
-    set treediffs($ids) $treediff
+    if {$limitdiffs && $viewfiles($curview) ne {}} {
+	set flist {}
+	foreach f $treediff {
+	    if {[path_filter $viewfiles($curview) $f]} {
+		lappend flist $f
+	    }
+	}
+	set treediffs($ids) $flist
+    } else {
+	set treediffs($ids) $treediff
+    }
     unset treepending
     if {$cmitmode eq "tree"} {
 	gettree $diffids
@@ -7565,7 +7572,7 @@ proc prefscan {} {
 proc prefsok {} {
     global maxwidth maxgraphpct
     global oldprefs prefstop showneartags showlocalchanges
-    global charspc ctext tabstop limitdiffs
+    global charspc ctext tabstop limitdiffs treediffs
 
     catch {destroy $prefstop}
     unset prefstop
@@ -7577,6 +7584,10 @@ proc prefsok {} {
 	    dohidelocalchanges
 	}
     }
+    if {$limitdiffs != $oldprefs(limitdiffs)} {
+	# treediffs elements are limited by path
+	catch {unset treediffs}
+    }
     if {$maxwidth != $oldprefs(maxwidth)
 	|| $maxgraphpct != $oldprefs(maxgraphpct)} {
 	redisplay