52645: unset through a nameref keep up-scope parameters declared unset

Othewise unset of a reference to a global wipes out all parameters of
the same name.

2 files changed, 11 insertions, 0 deletions

diff --git a/ChangeLog b/ChangeLog
index 9ab0218c9..31e90dfd3 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2024-03-01  Bart Schaefer  <schaefer@zsh.org>
+
+	* 52645: Src/builtin.c: unset through a nameref keep up-scope
+	parameters declared, and not wipe out the entire parameter stack
+
 2024-02-28  Bart Schaefer  <schaefer@zsh.org>
 
 	* 52619 (plus tests): Src/params.c, Test/A06assign.ztst: there
diff --git a/Src/builtin.c b/Src/builtin.c
index 44dfed651..83144677b 100644
--- a/Src/builtin.c
+++ b/Src/builtin.c
@@ -3932,8 +3932,14 @@ bin_unset(char *name, char **argv, Options ops, int func)
 	    }
 	} else {
 	    if (!OPT_ISSET(ops,'n')) {
+		int ref = (pm->node.flags & PM_NAMEREF);
 		if (!(pm = (Param)resolve_nameref(pm, NULL)))
 		    continue;
+		if (ref && pm->level < locallevel) {
+		    /* Just mark unset, do not remove from table */
+		    pm->node.flags |= PM_DECLARED|PM_UNSET;
+		    continue;
+		}
 	    }
 	    if (unsetparam_pm(pm, 0, 1))
 		returnval = 1;