Implement List.map4

compiler/test_gen/src/gen_list.rs

@@ -763,6 +763,37 @@ fn list_map_closure() {
     );
 }
 
+#[test]
+fn list_map4_group() {
+    assert_evals_to!(
+        indoc!(
+            r#"
+            List.map4 [1,2,3] [3,2,1] [2,1,3] [3,1,2] (\a, b, c, d -> Group a b c d)
+            "#
+        ),
+        RocList::from_slice(&[(1, 3, 2, 3), (2, 2, 1, 1), (3, 1, 3, 2)]),
+        RocList<(i64, i64, i64, i64)>
+    );
+}
+
+#[test]
+fn list_map4_different_length() {
+    assert_evals_to!(
+        indoc!(
+            r#"
+            List.map4
+                ["h", "i", "j", "k"]
+                ["o", "p", "q"]
+                ["l", "m"]
+                ["a"]
+                (\a, b, c, d -> Str.concat a (Str.concat b (Str.concat c d)))
+            "#
+        ),
+        RocList::from_slice(&[RocStr::from_slice("hola".as_bytes()),]),
+        RocList<RocStr>
+    );
+}
+
 #[test]
 fn list_map3_group() {
     assert_evals_to!(