diff --git a/lang/functions_test.go b/lang/functions_test.go
index 9233d0ff9..44908c8b8 100644
--- a/lang/functions_test.go
+++ b/lang/functions_test.go
@@ -592,11 +592,18 @@ func TestFunctions(t *testing.T) {
 
 		"slice": {
 			{
-				`slice(["a", "b", "c", "d"], 1, 3)`,
+				// force a list type here for testing
+				`slice(list("a", "b", "c", "d"), 1, 3)`,
 				cty.ListVal([]cty.Value{
 					cty.StringVal("b"), cty.StringVal("c"),
 				}),
 			},
+			{
+				`slice(["a", "b", 3, 4], 1, 3)`,
+				cty.TupleVal([]cty.Value{
+					cty.StringVal("b"), cty.NumberIntVal(3),
+				}),
+			},
 		},
 
 		"sort": {