Add value/key sign swap for Set.add and Map.set methods (#3681)

See also: ECMA-262 v6, 23.2.3.1 step 6 and 23.1.3.9 step 6

JerryScript-DCO-1.0-Signed-off-by: Adam Szilagyi aszilagy@inf.u-szeged.hu

jerry-core/ecma/operations/ecma-container-object.c

@@ -721,6 +721,31 @@ ecma_op_container_set_weak (ecma_object_t *const key_p, /**< key object */
   ecma_collection_push_back (refs_p, container_value);
 } /* ecma_op_container_set_weak */
 
+/**
+ * Helper method for the Map.prototype.set and Set.prototype.add methods to swap the sign of the given value if needed
+ *
+ * See also:
+ *          ECMA-262 v6, 23.2.3.1 step 6
+ *          ECMA-262 v6, 23.1.3.9 step 6
+ *
+ * @return ecma value
+ */
+static ecma_value_t
+ecma_op_container_set_noramlize_zero (ecma_value_t this_arg) /*< this arg */
+{
+  if (ecma_is_value_number (this_arg))
+  {
+    ecma_number_t number_value = ecma_get_number_from_value (this_arg);
+
+    if (JERRY_UNLIKELY (ecma_number_is_zero (number_value) && ecma_number_is_negative (number_value)))
+    {
+      return ecma_make_integer_value (0);
+    }
+  }
+
+  return this_arg;
+} /* ecma_op_container_set_noramlize_zero */
+
 /**
  * The generic Map prototype object's 'set' and Set prototype object's 'add' routine
  *
@@ -755,7 +780,10 @@ ecma_op_container_set (ecma_value_t this_arg, /**< this argument */
 
   if (entry_p == NULL)
   {
-    ecma_op_internal_buffer_append (container_p, key_arg, value_arg, lit_id);
+    ecma_op_internal_buffer_append (container_p,
+                                    ecma_op_container_set_noramlize_zero (key_arg),
+                                    value_arg,
+                                    lit_id);
 
 #if ENABLED (JERRY_ES2015_BUILTIN_WEAKMAP) ||  ENABLED (JERRY_ES2015_BUILTIN_WEAKSET)
     if ((map_object_p->u.class_prop.extra_info & ECMA_CONTAINER_FLAGS_WEAK) != 0)
@@ -767,7 +795,7 @@ ecma_op_container_set (ecma_value_t this_arg, /**< this argument */
   }
   else
   {
-    ecma_op_internal_buffer_update (entry_p, value_arg, lit_id);
+    ecma_op_internal_buffer_update (entry_p, ecma_op_container_set_noramlize_zero (value_arg), lit_id);
   }
 
   ecma_ref_object ((ecma_object_t *) map_object_p);

tests/jerry/es2015/map.js

@@ -147,3 +147,13 @@ try {
 } catch(e){}
 
 assert(closed === true);
+
+var map = new Map();
+map.set(-0, "foo");
+var k;
+map.forEach(function (value, key) {
+  k = 1 / key;
+});
+
+assert(k === Infinity);
+assert(map.get(+0) === "foo");

tests/jerry/es2015/set.js

@@ -126,3 +126,13 @@ s.forEach(function(value, key, thisArg) {
   assert (typeof thisArg === "object");
   assert(thisArg === s);
 });
+
+var set = new Set();
+set.add(-0);
+var k;
+set.forEach(function (value) {
+  k = 1 / value;
+});
+
+assert(k === Infinity);
+assert(set.has(+0) === true);