michael@0: // Map.prototype.delete works whether the key is present or not.
michael@0: 
michael@0: var m = new Map;
michael@0: var key = {};
michael@0: 
michael@0: // when the map is new
michael@0: assertEq(m.delete(key), false);
michael@0: assertEq(m.has(key), false);
michael@0: 
michael@0: // when the key is present
michael@0: assertEq(m.set(key, 'x'), undefined);
michael@0: assertEq(m.delete(key), true);
michael@0: assertEq(m.has(key), false);
michael@0: assertEq(m.get(key), undefined);
michael@0: 
michael@0: // when the key has already been deleted
michael@0: assertEq(m.delete(key), false);
michael@0: assertEq(m.has(key), false);