For historical/hysterical reasons, the (unused??) public routines Tcl_UpVar()

and Tcl_UpVar2() accept random garbage for a level argument (treat it as 1)
while the [upvar] command has come to reject such values as bad levels.
Add a test to call it to our attention if we ever change that disparity
so we do so only on purpose.

1 files changed, 4 insertions, 0 deletions

diff --git a/tests/upvar.test b/tests/upvar.test
index 5ea870d..437f422 100644
--- a/tests/upvar.test
+++ b/tests/upvar.test
@@ -356,6 +356,10 @@ test upvar-8.11 {upvar will not create a variable that looks like an array} -set
 test upvar-9.1 {Tcl_UpVar2 procedure} testupvar {
     list [catch {testupvar xyz a {} x global} msg] $msg
 } {1 {bad level "xyz"}}
+test upvar-9.1.1 {TclGetFrame, via Tcl_UpVar2} testupvar {
+    apply {{} {testupvar xyz a {} x local; set x foo}}
+    set a
+} foo
 test upvar-9.2 {Tcl_UpVar2 procedure} testupvar {
     catch {unset a}
     catch {unset x}