Diffusion Ant (type-hints-typescript) Code

ant/examples/spec/generators.js
899dad6b8a9etype-hints-typescript

generators.js
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			import { test, testDeep, summary } from './helpers.js';
			import { inspect } from 'node:util';

			console.log('Generator Tests\n');

			function* simple() {
			yield 1;
			yield 2;
			yield 3;
			}

			const gen = simple();
			test('generator object typeof', typeof gen, 'object');
			test('generator is iterable', gen[Symbol.iterator](), gen);

			try {
			new simple();
			test('new generator function throws', false, true);
			} catch {
			test('new generator function throws', true, true);
			}

			test('first yield', gen.next().value, 1);
			test('second yield', gen.next().value, 2);
			test('third yield', gen.next().value, 3);
			test('done', gen.next().done, true);

			function* withReturn() {
			yield 1;
			return 'final';
			}

			const gen2 = withReturn();
			test('yield before return', gen2.next().value, 1);
			const last = gen2.next();
			test('return value', last.value, 'final');
			test('return done', last.done, true);

			function* counter(start) {
			let i = start;
			while (true) yield i++;
			}

			const c = counter(10);
			test('counter 10', c.next().value, 10);
			test('counter 11', c.next().value, 11);
			test('counter 12', c.next().value, 12);

			function* range(start, end) {
			for (let i = start; i <= end; i++) yield i;
			}

			const arr = [...range(1, 5)];
			testDeep('spread generator', arr, [1, 2, 3, 4, 5]);

			let forOfSum = 0;
			for (const n of range(1, 4)) {
			forOfSum += n;
			}
			test('for-of generator', forOfSum, 10);

			function* twoWay() {
			const x = yield 1;
			const y = yield x + 1;
			yield y + 1;
			}

			const tw = twoWay();
			test('two way first', tw.next().value, 1);
			test('two way second', tw.next(10).value, 11);
			test('two way third', tw.next(20).value, 21);

			function runDynamicBool(source) {
			try {
			return Function(source)();
			} catch {
			return false;
			}
			}

			function* yieldStarArray() {
			yield* [4, 5, 6];
			}

			testDeep('yield* array', [...yieldStarArray()], [4, 5, 6]);

			function* yieldStarString() {
			yield* 'a\uD83D\uDCABb';
			}

			testDeep('yield* string keeps code points', [...yieldStarString()], ['a', '\uD83D\uDCAB', 'b']);

			function* yieldStarSparseArray() {
			yield* [7, , 9];
			}

			const sparse = yieldStarSparseArray();
			test('yield* sparse array first', sparse.next().value, 7);
			test('yield* sparse array hole value', sparse.next().value, undefined);
			test('yield* sparse array third', sparse.next().value, 9);
			test('yield* sparse array done', sparse.next().done, true);

			function makeIterable(values, methods = {}) {
			values = values.slice();
			values.push(undefined);
			const iterator = {
			next(value) {
			if (methods.next) return methods.next.call(this, value);
			return { value: values.shift(), done: values.length === 0 };
			},
			return: methods.return,
			throw: methods.throw
			};
			return {
			[Symbol.iterator]() {
			return iterator;
			}
			};
			}

			function* yieldStarIterable() {
			yield* makeIterable([10, 11, 12]);
			}

			testDeep('yield* generic iterable', [...yieldStarIterable()], [10, 11, 12]);

			function* yieldStarIterableInstance() {
			yield* Object.create(makeIterable([13, 14]));
			}

			testDeep('yield* iterable through prototype', [...yieldStarIterableInstance()], [13, 14]);

			function* innerGenerator() {
			yield 15;
			yield 16;
			return 17;
			}

			function* yieldStarGenerator() {
			return yield* innerGenerator();
			}

			const ysg = yieldStarGenerator();
			test('yield* generator first', ysg.next().value, 15);
			test('yield* generator second', ysg.next().value, 16);
			const ysgDone = ysg.next();
			test('yield* generator return value', ysgDone.value, 17);
			test('yield* generator return done', ysgDone.done, true);

			function* yieldStarReceivesSentValues() {
			return yield* (function* () {
			const received = yield 'ready';
			return received + 1;
			})();
			}

			const yss = yieldStarReceivesSentValues();
			test('yield* sent first', yss.next().value, 'ready');
			const yssDone = yss.next(40);
			test('yield* sent return value', yssDone.value, 41);
			test('yield* sent return done', yssDone.done, true);

			let yieldStarThrowCaught = false;
			function* yieldStarThrowForwarding() {
			yield* (function* () {
			try {
			yield 'before throw';
			} catch (e) {
			yieldStarThrowCaught = e === 'boom';
			return 'caught';
			}
			})();
			yield 'after throw';
			}

			const yst = yieldStarThrowForwarding();
			test('yield* throw forwarding first', yst.next().value, 'before throw');
			test('yield* throw forwarding continues outer', yst.throw('boom').value, 'after throw');
			test('yield* throw forwarding caught by delegate', yieldStarThrowCaught, true);

			let yieldStarClosed = '';
			const closingIter = makeIterable([1, 2, 3], {
			return() {
			yieldStarClosed += 'a';
			return { done: true };
			}
			});

			function* yieldStarReturnClosing() {
			try {
			yield* closingIter;
			} finally {
			yieldStarClosed += 'b';
			}
			}

			const ysrc = yieldStarReturnClosing();
			test('yield* return closing first', ysrc.next().value, 1);
			ysrc.return('closed');
			test('yield* return calls delegate and finally', yieldStarClosed, 'ab');

			let yieldStarThrowClosed = false;
			const noThrowIter = makeIterable([1, 2], {
			throw: undefined,
			return() {
			yieldStarThrowClosed = true;
			return { done: true };
			}
			});

			function* yieldStarThrowClosing() {
			try {
			yield* noThrowIter;
			} catch {}
			}

			const ystc = yieldStarThrowClosing();
			test('yield* throw closing first', ystc.next().value, 1);
			ystc.throw('close please');
			test('yield* throw without delegate throw closes iterator', yieldStarThrowClosed, true);

			try {
			(function* () {
			yield* 123;
			})().next();
			test('yield* non-iterable throws', false, true);
			} catch {
			test('yield* non-iterable throws', true, true);
			}

			function* catchesThrow() {
			try {
			yield 'waiting';
			} catch (e) {
			return e;
			}
			}

			const ct = catchesThrow();
			test('generator throw setup', ct.next().value, 'waiting');
			const ctDone = ct.throw('thrown value');
			test('generator throw caught value', ctDone.value, 'thrown value');
			test('generator throw caught done', ctDone.done, true);

			let finallyRan = false;
			function* returnRunsFinally() {
			try {
			yield 'open';
			} finally {
			finallyRan = true;
			}
			}

			const rrf = returnRunsFinally();
			test('generator return setup', rrf.next().value, 'open');
			const rrfDone = rrf.return('done now');
			test('generator return result value', rrfDone.value, 'done now');
			test('generator return result done', rrfDone.done, true);
			test('generator return runs finally', finallyRan, true);

			function* protoShapeFn() {}
			const protoShapeGen = protoShapeFn();
			const ownGeneratorProto = Object.getPrototypeOf(protoShapeGen);
			const sharedGeneratorProto = Object.getPrototypeOf(ownGeneratorProto);
			const iteratorProto = Object.getPrototypeOf(sharedGeneratorProto);
			const GeneratorFunction = protoShapeFn.constructor;
			test('generator function constructor name', GeneratorFunction.name, 'GeneratorFunction');
			test('generator function prototype chain', Object.getPrototypeOf(protoShapeFn), GeneratorFunction.prototype);
			test('generator function prototype tag', GeneratorFunction.prototype[Symbol.toStringTag], 'GeneratorFunction');
			test('generator function toStringTag', Object.prototype.toString.call(protoShapeFn), '[object GeneratorFunction]');
			test('generator function inspect tag', inspect(protoShapeFn), '[GeneratorFunction: protoShapeFn]');
			test('generator instance uses function prototype', ownGeneratorProto, protoShapeFn.prototype);
			test('generator shared prototype has next', sharedGeneratorProto.hasOwnProperty('next'), true);
			test('generator Symbol.iterator inherited from iterator prototype', iteratorProto.hasOwnProperty(Symbol.iterator), true);

			test(
			'shorthand object generator method',
			runDynamicBool(`
			const o = {
			*generator() {
			yield 5;
			yield 6;
			}
			};
			const it = o.generator();
			return it.next().value === 5 &&
			it.next().value === 6 &&
			it.next().done === true;
			`),
			true
			);

			test(
			'shorthand computed generator method',
			runDynamicBool(`
			const name = 'generator';
			const o = {
			*[name]() {
			yield 7;
			yield 8;
			}
			};
			const it = o.generator();
			return it.next().value === 7 &&
			it.next().value === 8 &&
			it.next().done === true;
			`),
			true
			);

			test(
			'shorthand string-keyed generator method',
			runDynamicBool(`
			const o = {
			*"foo bar"() {
			yield 9;
			yield 10;
			}
			};
			const it = o['foo bar']();
			return it.next().value === 9 &&
			it.next().value === 10 &&
			it.next().done === true;
			`),
			true
			);

			test(
			'class generator method',
			runDynamicBool(`
			class C {
			*generator() {
			yield 11;
			yield 12;
			}
			}
			const it = new C().generator();
			return it.next().value === 11 &&
			it.next().value === 12 &&
			it.next().done === true;
			`),
			true
			);

			test(
			'class computed generator method',
			runDynamicBool(`
			const name = 'generator';
			class C {
			*[name]() {
			yield 13;
			yield 14;
			}
			}
			const it = new C().generator();
			return it.next().value === 13 &&
			it.next().value === 14 &&
			it.next().done === true;
			`),
			true
			);

			test(
			'generator method cannot be constructor',
			runDynamicBool(`
			const o = {
			*generator() {
			yield 1;
			}
			};
			try {
			new o.generator();
			return false;
			} catch {
			return true;
			}
			`),
			true
			);

			test(
			'class generator constructor syntax rejected',
			runDynamicBool(`
			try {
			Function('class Bad { *constructor() { yield 1; } }');
			return false;
			} catch {
			return true;
			}
			`),
			true
			);

			summary();

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