Add more map tests

Author: jamesls

tests/compliance/functions.json

@@ -759,7 +759,8 @@
          {"a": 10, "b": 7, "c": "z"},
          {"a": 10, "b": 8, "c": null},
          {"a": 10, "b": 9}
-    ]
+    ],
+    "empty": []
   },
   "cases": [
     {
@@ -773,6 +774,10 @@
     {
       "expression": "map(&a, badkey)",
       "error": "invalid-type"
+    },
+    {
+      "expression": "map(&foo, empty)",
+      "result": []
     }
   ]
 }, {
@@ -802,5 +807,15 @@
       "result": [null, null, null]
     }
   ]
+}, {
+  "given": {
+    "array": [[1, 2, 3, [4]], [5, 6, 7, [8, 9]]]
+  },
+  "cases": [
+    {
+      "expression": "map(&[], array)",
+      "result": [[1, 2, 3, 4], [5, 6, 7, 8, 9]]
+    }
+  ]
 }
 ]