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

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);