Merge 8.6

2 files changed, 11 insertions, 3 deletions

diff --git a/library/tearoff.tcl b/library/tearoff.tcl
index b500023..c2d2d6b 100644
--- a/library/tearoff.tcl
+++ b/library/tearoff.tcl
@@ -154,7 +154,9 @@ proc ::tk::MenuDup {src dst type} {
     # Copy tags to x, replacing each substring of src with dst.
 
     while {[set index [string first $src $tags]] != -1} {
-	append x [string range $tags 0 [expr {$index - 1}]]$dst
+	if {$index > 0} {
+	    append x [string range $tags 0 [expr {$index - 1}]]$dst
+	}
 	set tags [string range $tags [expr {$index + $srcLen}] end]
     }
     append x $tags
@@ -169,7 +171,9 @@ proc ::tk::MenuDup {src dst type} {
 	# Copy script to x, replacing each substring of event with dst.
 
 	while {[set index [string first $event $script]] != -1} {
-	    append x [string range $script 0 [expr {$index - 1}]]
+	    if {$index > 0} {
+		append x [string range $script 0 [expr {$index - 1}]]
+	    }
 	    append x $dst
 	    set script [string range $script [expr {$index + $eventLen}] end]
 	}
diff --git a/library/text.tcl b/library/text.tcl
index 62db560..6d3df8e 100644
--- a/library/text.tcl
+++ b/library/text.tcl
@@ -1278,7 +1278,11 @@ proc ::tk::TextUndoRedoProcessMarks {w} {
     set nUndoMarks [llength $undoMarks]
     set n [expr {$nUndoMarks / 2}]
     set undoMarks [lsort -dictionary $undoMarks]
-    set Lmarks [lrange $undoMarks 0 [expr {$n - 1}]]
+    if {$n > 0} {
+	set Lmarks [lrange $undoMarks 0 [expr {$n - 1}]]
+    } else {
+	set Lmarks {}
+    }
     set Rmarks [lrange $undoMarks $n [llength $undoMarks]]
     foreach Lmark $Lmarks Rmark $Rmarks {
         lappend indices [$w index $Lmark] [$w index $Rmark]