From a663c11e5012dafd387cb5a73650bb5a59273bea Mon Sep 17 00:00:00 2001
From: Andy Chu <andy@oilshell.org>
Date: Fri, 17 Apr 2020 10:21:33 -0700
Subject: [PATCH] [spec/builtin-vars] Simple case to show 'local unset cell'
 semantics.

Related to #706.
---
 spec/builtin-vars.test.sh | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/spec/builtin-vars.test.sh b/spec/builtin-vars.test.sh
index 30ee194020..cba51ed639 100644
--- a/spec/builtin-vars.test.sh
+++ b/spec/builtin-vars.test.sh
@@ -368,6 +368,28 @@ level2=yy
 level2=
 ## END
 
+#### unset of local reveals variable in higher scope
+
+# Oil has a RARE behavior here (matching yash and mksh), but at least it's
+# consistent.
+
+x=global
+f() {
+  local x=foo
+  echo x=$x
+  unset x
+  echo x=$x
+}
+f
+## STDOUT:
+x=foo
+x=global
+## END
+## OK dash/bash/zsh/ash STDOUT:
+x=foo
+x=
+## END
+
 #### Unset invalid variable name
 unset %
 echo status=$?