tests: shell: Add test for set element leak bug

This tests for a bug where a repeated element is added and the set
elements counter is incorrectly increased.

Signed-off-by: Elise Lennion <elise.lennion@gmail.com>

diff --git a/tests/shell/testcases/sets/0016element_leak_0 b/tests/shell/testcases/sets/0016element_leak_0
new file mode 100755 (executable)
index 0000000..5675db3
--- /dev/null
+++ b/tests/shell/testcases/sets/0016element_leak_0
@@ -0,0 +1,11 @@
+#!/bin/bash
+
+# This tests for a bug where a repeated element is added and the set
+# elements counter is incorrectly increased.
+
+set -e
+$NFT add table x
+$NFT add set x s {type ipv4_addr\; size 2\;}
+$NFT add element x s {1.1.1.1}
+$NFT add element x s {1.1.1.1}
+$NFT add element x s {1.1.1.1}