michael@0: // This file was written by Andy Wingo <wingo@igalia.com> and originally
michael@0: // contributed to V8 as generators-runtime.js, available here:
michael@0: //
michael@0: // http://code.google.com/p/v8/source/browse/branches/bleeding_edge/test/mjsunit/harmony/generators-runtime.js
michael@0: 
michael@0: // Test aspects of the generator runtime.
michael@0: 
michael@0: // See http://people.mozilla.org/~jorendorff/es6-draft.html#sec-15.19.3.
michael@0: 
michael@0: function assertSyntaxError(str) {
michael@0:     assertThrowsInstanceOf(Function(str), SyntaxError);
michael@0: }
michael@0: 
michael@0: 
michael@0: function f() { }
michael@0: function* g() { yield 1; }
michael@0: var GeneratorFunctionPrototype = Object.getPrototypeOf(g);
michael@0: var GeneratorFunction = GeneratorFunctionPrototype.constructor;
michael@0: var GeneratorObjectPrototype = GeneratorFunctionPrototype.prototype;
michael@0: // FIXME: This should be a symbol.
michael@0: var std_iterator = "@@iterator";
michael@0: 
michael@0: 
michael@0: // A generator function should have the same set of properties as any
michael@0: // other function.
michael@0: function TestGeneratorFunctionInstance() {
michael@0:     var f_own_property_names = Object.getOwnPropertyNames(f);
michael@0:     var g_own_property_names = Object.getOwnPropertyNames(g);
michael@0: 
michael@0:     f_own_property_names.sort();
michael@0:     g_own_property_names.sort();
michael@0: 
michael@0:     assertDeepEq(f_own_property_names, g_own_property_names);
michael@0:     var i;
michael@0:     for (i = 0; i < f_own_property_names.length; i++) {
michael@0:         var prop = f_own_property_names[i];
michael@0:         var f_desc = Object.getOwnPropertyDescriptor(f, prop);
michael@0:         var g_desc = Object.getOwnPropertyDescriptor(g, prop);
michael@0:         assertEq(f_desc.configurable, g_desc.configurable, prop);
michael@0:         assertEq(f_desc.writable, g_desc.writable, prop);
michael@0:         assertEq(f_desc.enumerable, g_desc.enumerable, prop);
michael@0:     }
michael@0: }
michael@0: TestGeneratorFunctionInstance();
michael@0: 
michael@0: 
michael@0: // Generators have an additional object interposed in the chain between
michael@0: // themselves and Function.prototype.
michael@0: function TestGeneratorFunctionPrototype() {
michael@0:     // Sanity check.
michael@0:     assertEq(Object.getPrototypeOf(f), Function.prototype);
michael@0:     assertNotEq(GeneratorFunctionPrototype, Function.prototype);
michael@0:     assertEq(Object.getPrototypeOf(GeneratorFunctionPrototype),
michael@0:                Function.prototype);
michael@0:     assertEq(Object.getPrototypeOf(function* () {}),
michael@0:                GeneratorFunctionPrototype);
michael@0: }
michael@0: TestGeneratorFunctionPrototype();
michael@0: 
michael@0: 
michael@0: // Functions that we associate with generator objects are actually defined by
michael@0: // a common prototype.
michael@0: function TestGeneratorObjectPrototype() {
michael@0:     assertEq(Object.getPrototypeOf(GeneratorObjectPrototype),
michael@0:                Object.prototype);
michael@0:     assertEq(Object.getPrototypeOf((function*(){yield 1}).prototype),
michael@0:                GeneratorObjectPrototype);
michael@0: 
michael@0:     var expected_property_names = ["next", "throw", "constructor", std_iterator];
michael@0:     var found_property_names =
michael@0:         Object.getOwnPropertyNames(GeneratorObjectPrototype);
michael@0: 
michael@0:     expected_property_names.sort();
michael@0:     found_property_names.sort();
michael@0: 
michael@0:     assertDeepEq(found_property_names, expected_property_names);
michael@0: }
michael@0: TestGeneratorObjectPrototype();
michael@0: 
michael@0: 
michael@0: // This tests the object that would be called "GeneratorFunction", if it were
michael@0: // like "Function".
michael@0: function TestGeneratorFunction() {
michael@0:     assertEq(GeneratorFunctionPrototype, GeneratorFunction.prototype);
michael@0:     assertTrue(g instanceof GeneratorFunction);
michael@0: 
michael@0:     assertEq(Function, Object.getPrototypeOf(GeneratorFunction));
michael@0:     assertTrue(g instanceof Function);
michael@0: 
michael@0:     assertEq("function* g() { yield 1; }", g.toString());
michael@0: 
michael@0:     // Not all functions are generators.
michael@0:     assertTrue(f instanceof Function);  // Sanity check.
michael@0:     assertFalse(f instanceof GeneratorFunction);
michael@0: 
michael@0:     assertTrue((new GeneratorFunction()) instanceof GeneratorFunction);
michael@0:     assertTrue(GeneratorFunction() instanceof GeneratorFunction);
michael@0: 
michael@0:     assertTrue(GeneratorFunction('yield 1') instanceof GeneratorFunction);
michael@0:     assertTrue(GeneratorFunction('return 1') instanceof GeneratorFunction);
michael@0:     assertTrue(GeneratorFunction('a', 'yield a') instanceof GeneratorFunction);
michael@0:     assertTrue(GeneratorFunction('a', 'return a') instanceof GeneratorFunction);
michael@0:     assertTrue(GeneratorFunction('a', 'return a') instanceof GeneratorFunction);
michael@0:     assertSyntaxError("GeneratorFunction('yield', 'return yield')");
michael@0:     assertTrue(GeneratorFunction('with (x) return foo;') instanceof GeneratorFunction);
michael@0:     assertSyntaxError("GeneratorFunction('\"use strict\"; with (x) return foo;')");
michael@0: 
michael@0:     // Doesn't matter particularly what string gets serialized, as long
michael@0:     // as it contains "function*" and "yield 10".
michael@0:     assertEq(GeneratorFunction('yield 10').toString(),
michael@0:              "function* anonymous() {\nyield 10\n}");
michael@0: }
michael@0: TestGeneratorFunction();
michael@0: 
michael@0: 
michael@0: function TestPerGeneratorPrototype() {
michael@0:     assertNotEq((function*(){}).prototype, (function*(){}).prototype);
michael@0:     assertNotEq((function*(){}).prototype, g.prototype);
michael@0:     assertEq(typeof GeneratorFunctionPrototype, "object");
michael@0:     assertEq(g.prototype.__proto__.constructor, GeneratorFunctionPrototype, "object");
michael@0:     assertEq(Object.getPrototypeOf(g.prototype), GeneratorObjectPrototype);
michael@0:     assertFalse(g.prototype instanceof Function);
michael@0:     assertEq(typeof (g.prototype), "object");
michael@0: 
michael@0:     assertDeepEq(Object.getOwnPropertyNames(g.prototype), []);
michael@0: }
michael@0: TestPerGeneratorPrototype();
michael@0: 
michael@0: 
michael@0: if (typeof reportCompare == "function")
michael@0:     reportCompare(true, true);