1 files changed, 14 insertions, 0 deletions
diff --git a/test/gleam/map_test.gleam b/test/gleam/map_test.gleam
index 5cfb37d..75fb78d 100644
--- a/test/gleam/map_test.gleam
+++ b/test/gleam/map_test.gleam
@@ -361,3 +361,17 @@ pub fn peters_bug_test() {
   |> map.get(0)
   |> should.equal(Error(Nil))
 }
+
+pub fn zero_must_be_contained_test() {
+  let map =
+    map.new()
+    |> map.insert(0, Nil)
+
+  map
+  |> map.get(0)
+  |> should.equal(Ok(Nil))
+
+  map
+  |> map.has_key(0)
+  |> should.equal(True)
+}