import {
assert,
assertEquals,
+ assertNotStrictEquals,
+ assertSpyCall,
+ assertSpyCalls,
assertStrictEquals,
assertThrows,
describe,
it,
+ spy,
} from "./dev-deps.js";
import {
bind,
createArrowFunction,
createCallableFunction,
createIllegalConstructor,
+ createProxyConstructor,
identity,
isCallable,
isConstructor,
+ maybe,
ordinaryHasInstance,
} from "./function.js";
Object.getPrototypeOf(constructor.prototype),
Object.prototype,
);
- console.dir(
- Object.getOwnPropertyDescriptors(constructor.prototype),
- );
assertEquals(
constructor.prototype,
Object.create(Object.prototype, {
it("[[Call]] returns a correctly‐formed constructor when provided one argument", () => {
const constructorPrototype = Object.create(null, {
name: { value: "etaoin" },
+ length: { value: "3" },
prototype: { value: {} },
});
const constructor = createIllegalConstructor(
constructorPrototype,
);
assert(Object.hasOwn(constructor, "prototype"));
- assertEquals(
+ assertStrictEquals(
constructor.prototype,
constructorPrototype.prototype,
);
.writable,
);
assertStrictEquals(constructor.name, "etaoin");
+ assertStrictEquals(constructor.length, 3);
+ });
+
+ it("[[Call]] allows the length to be overridden", () => {
+ assertStrictEquals(
+ createIllegalConstructor(
+ function etaoin() {},
+ { length: 100 },
+ ).length,
+ 100,
+ );
+ });
+
+ it("[[Call]] allows the name to be overridden", () => {
+ assertStrictEquals(
+ createIllegalConstructor(
+ function etaoin() {},
+ { name: "shrdlu" },
+ ).name,
+ "shrdlu",
+ );
+ });
+
+ it("[[Call]] allows the prototype to be overridden", () => {
+ const obj = {};
+ assertStrictEquals(
+ createIllegalConstructor(
+ function etaoin() {},
+ { prototype: obj },
+ ).prototype,
+ obj,
+ );
});
it("[[Construct]] throws an error", () => {
assertThrows(() => new createIllegalConstructor(function () {}));
});
+ describe(".length", () => {
+ it("[[Get]] returns the correct length", () => {
+ assertStrictEquals(createIllegalConstructor.length, 1);
+ });
+ });
+
+ describe(".name", () => {
+ it("[[Get]] returns the correct name", () => {
+ assertStrictEquals(
+ createIllegalConstructor.name,
+ "createIllegalConstructor",
+ );
+ });
+ });
+
describe("~", () => {
it("[[Call]] throws an error", () => {
assertThrows(() => {
});
});
});
+});
+
+describe("createProxyConstructor", () => {
+ it("[[Call]] returns a constructor", () => {
+ assert(isConstructor(createProxyConstructor({})));
+ });
+
+ it("[[Call]] throws with no arguments", () => {
+ assertThrows(() => createProxyConstructor());
+ });
+
+ it("[[Call]] throws if the second argument is not a constructor or undefined", () => {
+ assertThrows(() => createProxyConstructor({}, () => {}));
+ });
+
+ it("[[Call]] throws if the third argument is not a constructor or undefined", () => {
+ assertThrows(() =>
+ createProxyConstructor({}, undefined, () => {})
+ );
+ });
+
+ it("[[Call]] creates a proper proxy constructor", () => {
+ const constructorPrototype = function etaoin(_) {};
+ const constructor = class Constructor
+ extends constructorPrototype {
+ constructor(_1, _2, _3) {}
+ };
+ const proxyConstructor = createProxyConstructor(
+ {},
+ constructor,
+ );
+ assert(isConstructor(proxyConstructor));
+ assertStrictEquals(
+ Object.getPrototypeOf(proxyConstructor),
+ Proxy,
+ );
+ assertStrictEquals(proxyConstructor.prototype, undefined);
+ assertStrictEquals(proxyConstructor.name, "ConstructorProxy");
+ assertStrictEquals(proxyConstructor.length, 3);
+ });
+
+ it("[[Call]] allows the length to be overridden", () => {
+ assertStrictEquals(
+ createProxyConstructor({}, undefined, undefined, {
+ length: 100,
+ }).length,
+ 100,
+ );
+ });
+
+ it("[[Call]] allows the name to be overridden", () => {
+ assertStrictEquals(
+ createProxyConstructor({}, function etaoin() {}, undefined, {
+ name: "shrdlu",
+ }).name,
+ "shrdlu",
+ );
+ });
+
+ it("[[Call]] does not allow the prototype to be overridden", () => {
+ assertStrictEquals(
+ createProxyConstructor({}, undefined, undefined, {
+ prototype: {},
+ }).prototype,
+ undefined,
+ );
+ });
+
+ it("[[Construct]] throws an error", () => {
+ assertThrows(() => new createProxyConstructor({}));
+ });
describe(".length", () => {
it("[[Get]] returns the correct length", () => {
- assertStrictEquals(createIllegalConstructor.length, 1);
+ assertStrictEquals(createProxyConstructor.length, 2);
});
});
describe(".name", () => {
it("[[Get]] returns the correct name", () => {
assertStrictEquals(
- createIllegalConstructor.name,
- "createIllegalConstructor",
+ createProxyConstructor.name,
+ "createProxyConstructor",
+ );
+ });
+ });
+
+ describe("~", () => {
+ it("[[Call]] throws an error", () => {
+ assertThrows(() => {
+ createProxyConstructor({})();
+ });
+ });
+
+ it("[[Construct]] produces a proxy", () => {
+ const obj = {};
+ const proxyConstructor = createProxyConstructor({
+ get(O, P, Receiver) {
+ if (P === "etaoin") {
+ return Reflect.get(O, P, Receiver) ?? "success";
+ } else {
+ return Reflect.get(O, P, Receiver);
+ }
+ },
+ }, function () {
+ return obj;
+ });
+ const proxy = new proxyConstructor();
+ assertStrictEquals(proxy.etaoin, "success");
+ obj.etaoin = "shrdlu";
+ assertStrictEquals(proxy.etaoin, "shrdlu");
+ });
+
+ it("[[Construct]] receives the expected new.target", () => {
+ const constructor = function Constructor() {
+ return { name: new.target.name };
+ };
+ assertStrictEquals(
+ new (createProxyConstructor({}, constructor))().name,
+ "Constructor",
+ );
+ assertStrictEquals(
+ new (createProxyConstructor(
+ {},
+ constructor,
+ function NewTarget() {},
+ ))().name,
+ "NewTarget",
+ );
+ });
+ });
+
+ describe("~is[[.name]]", () => {
+ it("[[GetOwnProperty]] defines the appropriate method", () => {
+ assertNotStrictEquals(
+ Object.getOwnPropertyDescriptor(
+ createProxyConstructor({}),
+ "isProxy",
+ ),
+ undefined,
+ );
+ assertNotStrictEquals(
+ Object.getOwnPropertyDescriptor(
+ createProxyConstructor({}, function Base() {}),
+ "isBaseProxy",
+ ),
+ undefined,
+ );
+ assertNotStrictEquals(
+ Object.getOwnPropertyDescriptor(
+ createProxyConstructor({}, function Bad() {}, undefined, {
+ name: "⸺",
+ }),
+ "is⸺",
+ ),
+ undefined,
+ );
+ });
+
+ it("[[GetOwnProperty]] has the correct descriptor", () => {
+ const proxyConstructor = createProxyConstructor({});
+ assertEquals(
+ Object.getOwnPropertyDescriptor(
+ proxyConstructor,
+ "isProxy",
+ ),
+ {
+ configurable: true,
+ enumerable: false,
+ value: proxyConstructor.isProxy,
+ writable: true,
+ },
+ );
+ });
+
+ it("[[Call]] returns true for created proxies", () => {
+ const proxyConstructor = createProxyConstructor({});
+ const proxy = new proxyConstructor();
+ assertStrictEquals(
+ proxyConstructor.isProxy(proxy),
+ true,
+ );
+ });
+
+ it("[[Call]] returns false for nonproxies", () => {
+ const constructor = function Base() {};
+ const proxyConstructor = createProxyConstructor({}, constructor);
+ assertStrictEquals(
+ proxyConstructor.isBaseProxy(new constructor()),
+ false,
+ );
+ });
+
+ it("[[Construct]] throws an error", () => {
+ const proxyConstructor = createProxyConstructor({});
+ assertThrows(() => new proxyConstructor.isProxy({}));
+ });
+
+ describe(".length", () => {
+ it("[[Get]] returns the correct length", () => {
+ const proxyConstructor = createProxyConstructor({});
+ assertStrictEquals(proxyConstructor.isProxy.length, 1);
+ });
+ });
+
+ describe(".name", () => {
+ it("[[Get]] returns the correct name", () => {
+ const proxyConstructor = createProxyConstructor({});
+ assertStrictEquals(proxyConstructor.isProxy.name, "isProxy");
+ const otherProxyConstructor = createProxyConstructor(
+ {},
+ function Base() {},
+ );
+ assertStrictEquals(
+ otherProxyConstructor.isBaseProxy.name,
+ "isBaseProxy",
+ );
+ });
+ });
+ });
+
+ describe("~length", () => {
+ it("[[GetOwnProperty]] has the correct descriptor", () => {
+ assertEquals(
+ Object.getOwnPropertyDescriptor(
+ createProxyConstructor({}),
+ "length",
+ ),
+ {
+ configurable: true,
+ enumerable: false,
+ value: 1,
+ writable: false,
+ },
+ );
+ });
+ });
+
+ describe("~name", () => {
+ it("[[GetOwnProperty]] has the correct descriptor", () => {
+ assertEquals(
+ Object.getOwnPropertyDescriptor(
+ createProxyConstructor({}),
+ "name",
+ ),
+ {
+ configurable: true,
+ enumerable: false,
+ value: "Proxy",
+ writable: false,
+ },
+ );
+ });
+ });
+
+ describe("~prototype", () => {
+ it("[[GetOwnProperty]] has the correct descriptor", () => {
+ assertEquals(
+ Object.getOwnPropertyDescriptor(
+ createProxyConstructor({}),
+ "prototype",
+ ),
+ {
+ configurable: false,
+ enumerable: false,
+ value: undefined,
+ writable: false,
+ },
+ );
+ });
+ });
+
+ describe("~revocable", () => {
+ it("[[Call]] produces a revocable proxy", () => {
+ const obj = {};
+ const proxyConstructor = createProxyConstructor({
+ get(O, P, Receiver) {
+ if (P === "etaoin") {
+ return Reflect.get(O, P, Receiver) ?? "success";
+ } else {
+ return Reflect.get(O, P, Receiver);
+ }
+ },
+ }, function () {
+ return obj;
+ });
+ const { proxy, revoke } = proxyConstructor.revocable();
+ assertStrictEquals(proxy.etaoin, "success");
+ obj.etaoin = "shrdlu";
+ assertStrictEquals(proxy.etaoin, "shrdlu");
+ revoke();
+ assertThrows(() => proxy.etaoin);
+ });
+
+ it("[[Call]] receives the expected new.target", () => {
+ const constructor = function Constructor() {
+ return { name: new.target.name };
+ };
+ assertStrictEquals(
+ createProxyConstructor({}, constructor).revocable().proxy.name,
+ "Constructor",
+ );
+ assertStrictEquals(
+ createProxyConstructor(
+ {},
+ constructor,
+ function NewTarget() {},
+ ).revocable().proxy.name,
+ "NewTarget",
+ );
+ });
+
+ it("[[Construct]] throws an error", () => {
+ assertThrows(() => new (createProxyConstructor({})).revocable());
+ });
+
+ it("[[GetOwnProperty]] has the correct descriptor", () => {
+ const proxyConstructor = createProxyConstructor({});
+ assertEquals(
+ Object.getOwnPropertyDescriptor(proxyConstructor, "revocable"),
+ {
+ configurable: true,
+ enumerable: false,
+ value: proxyConstructor.revocable,
+ writable: true,
+ },
);
});
});
});
});
+describe("maybe", () => {
+ it("[[Call]] calls if not nullish", () => {
+ const wrapper = spy(() => "success");
+ assertStrictEquals(maybe(0, wrapper), "success");
+ assertSpyCalls(wrapper, 1);
+ assertSpyCall(wrapper, 0, {
+ args: [0],
+ self: undefined,
+ returned: "success",
+ });
+ });
+
+ it("[[Call]] does not call if nullish", () => {
+ const wrapper = spy(() => "success");
+ assertStrictEquals(maybe(null, wrapper), null);
+ assertStrictEquals(maybe(undefined, wrapper), undefined);
+ assertSpyCalls(wrapper, 0);
+ });
+
+ it("[[Construct]] throws an error", () => {
+ assertThrows(() => new maybe(true, ($) => $));
+ });
+
+ describe(".length", () => {
+ it("[[Get]] returns the correct length", () => {
+ assertStrictEquals(maybe.length, 2);
+ });
+ });
+
+ describe(".name", () => {
+ it("[[Get]] returns the correct name", () => {
+ assertStrictEquals(maybe.name, "maybe");
+ });
+ });
+});
+
describe("ordinaryHasInstance", () => {
it("[[Call]] walks the prototype chain", () => {
const constructor = class {