angular/packages/forms/signals/test/node/submit.spec.ts
Miles Malerba b8314bd340 feat(forms): add experimental signal-based forms (#63408)
This commit introduces an experimental version of a new signal-based forms API for Angular. This new API aims to explore how signals can be leveraged to create a more declarative, intuitive, and reactive way of handling forms.

The primary goals of this new signal-based approach are:

*   **Signal-centric Design:** Place signals at the core of the forms experience, enabling a truly reactive programming model for form state and logic.
*   **Declarative Logic:** Allow developers to define form behavior, such as validation and conditional fields, declaratively using TypeScript. This moves logic out of the template and into a typed, testable schema.
*   **Developer-Owned Data Model:** The library does not maintain a copy of data in a form model, but instead read and write it via a developer-provided `WritableSignal`, eliminating the need for applications to synchronize their data with the form system.
*   **Interoperability:** A key design goal is seamless interoperability with existing reactive forms, allowing for incremental adoption.
*   **Bridging Template and Reactive Forms:** This exploration hopes to close the gap between template and reactive forms, offering a unified and more powerful approach that combines the best aspects of both.

This initial version of the experimental API includes the core building blocks, such as the `form()` function, `Field` and `FieldState` objects, and a `[control]` directive for binding to UI elements. It also introduces a schema-based system for defining validation, conditional logic, and other form behaviors.

Note: This is an early, experimental API. It is not yet complete and is subject to change based on feedback and further exploration.

Co-authored-by: Kirill Cherkashin <kirts@google.com>
Co-authored-by: Alex Rickabaugh <alxhub@users.noreply.github.com>
Co-authored-by: Leon Senft <leonsenft@users.noreply.github.com>
Co-authored-by: Dylan Hunn <dylhunn@gmail.com>
Co-authored-by: Michael Small <michael-small@users.noreply.github.com>

PR Close #63408
2025-08-28 09:02:43 -07:00

295 lines
8.1 KiB
TypeScript

/**
* @license
* Copyright Google LLC All Rights Reserved.
*
* Use of this source code is governed by an MIT-style license that can be
* found in the LICENSE file at https://angular.dev/license
*/
import {Injector, resource, signal} from '@angular/core';
import {TestBed} from '@angular/core/testing';
import {
customError,
form,
required,
requiredError,
submit,
validateAsync,
ValidationError,
} from '../../public_api';
describe('submit', () => {
it('fails fast on invalid form', async () => {
const data = signal({first: '', last: ''});
const f = form(
data,
(name) => {
required(name.first);
},
{injector: TestBed.inject(Injector)},
);
await submit(f, async (form) => {
fail('Submit action should run not on invalid form');
});
expect(f.first().errors()).toEqual([requiredError({field: f.first})]);
});
it('should not block on pending async validators', async () => {
const data = signal('');
const resolvers = promiseWithResolvers();
const f = form(
data,
(p) => {
validateAsync(p, {
params: ({value}) => value(),
factory: (params) =>
resource({
params,
loader: () => resolvers.promise,
}),
errors: () => {},
});
},
{injector: TestBed.inject(Injector)},
);
expect(f().pending()).toBe(true);
const submitSpy = jasmine.createSpy();
await submit(f, submitSpy);
expect(f().pending()).toBe(true);
expect(submitSpy).toHaveBeenCalled();
});
it('maps error to a field', async () => {
const data = signal({first: '', last: ''});
const f = form(
data,
(name) => {
// first name required if last name specified
required(name.first, {when: ({valueOf}) => valueOf(name.last) !== ''});
},
{injector: TestBed.inject(Injector)},
);
await submit(f, (form) => {
return Promise.resolve(
customError({
kind: 'lastName',
field: form.last,
}),
);
});
expect(f.last().errors()).toEqual([customError({kind: 'lastName', field: f.last})]);
});
it('maps errors to multiple fields', async () => {
const data = signal({first: '', last: ''});
const f = form(data, {injector: TestBed.inject(Injector)});
await submit(f, (form) => {
return Promise.resolve([
customError({
kind: 'firstName',
field: form.first,
}),
customError({
kind: 'lastName',
field: form.last,
}),
customError({
kind: 'lastName2',
field: form.last,
}),
]);
});
expect(f.first().errors()).toEqual([customError({kind: 'firstName', field: f.first})]);
expect(f.last().errors()).toEqual([
customError({kind: 'lastName', field: f.last}),
customError({kind: 'lastName2', field: f.last}),
]);
});
it('can read value from field state', async () => {
const initialValue = {first: 'meow', last: 'wuf'};
const data = signal(initialValue);
const f = form(
data,
(name) => {
// first name required if last name specified
required(name.first, {when: ({valueOf}) => valueOf(name.last) !== ''});
},
{injector: TestBed.inject(Injector)},
);
const submitSpy = jasmine.createSpy('submit');
await submit(f, (form) => {
submitSpy(form().value());
return Promise.resolve();
});
expect(submitSpy).toHaveBeenCalledWith(initialValue);
});
it('maps untargeted errors to form root', async () => {
const data = signal({first: '', last: ''});
const f = form(
data,
(name) => {
// first name required if last name specified
required(name.first, {when: ({valueOf}) => valueOf(name.last) !== ''});
},
{injector: TestBed.inject(Injector)},
);
await submit(f, () => {
return Promise.resolve(customError());
});
expect(f().errors()).toEqual([customError({field: f})]);
});
it('marks the form as submitting', async () => {
const initialValue = {first: 'meow', last: 'wuf'};
const data = signal(initialValue);
const f = form(
data,
(name) => {
// first name required if last name specified
required(name.first, {when: ({valueOf}) => valueOf(name.last) !== ''});
},
{injector: TestBed.inject(Injector)},
);
expect(f().submitting()).toBe(false);
const {promise, resolve} = promiseWithResolvers<ValidationError[]>();
const result = submit(f, () => promise);
expect(f().submitting()).toBe(true);
resolve([]);
await result;
});
it('marks descendants as submitting', async () => {
const initialValue = {a: {b: 12}};
const data = signal(initialValue);
const f = form(data, {injector: TestBed.inject(Injector)});
expect(f.a.b().submitting()).toBe(false);
const {promise, resolve} = promiseWithResolvers<ValidationError[]>();
const result = submit(f, () => promise);
expect(f.a.b().submitting()).toBe(true);
resolve([]);
await result;
});
it('marks the form as touched', async () => {
const initialValue = {first: 'meow', last: 'wuf'};
const data = signal(initialValue);
const f = form(data, {injector: TestBed.inject(Injector)});
expect(f().touched()).toBe(false);
await submit(f, async () => []);
expect(f().touched()).toBe(true);
});
it('marks descendants as touched', async () => {
const initialValue = {a: {b: 12}};
const data = signal(initialValue);
const f = form(data, {injector: TestBed.inject(Injector)});
expect(f.a.b().touched()).toBe(false);
await submit(f, async () => []);
expect(f.a.b().touched()).toBe(true);
});
it('works on child fields', async () => {
const initialValue = {first: 'meow', last: 'wuf'};
const data = signal(initialValue);
const f = form(
data,
(name) => {
// first name required if last name specified
required(name.first, {
when: ({valueOf}) => valueOf(name.last) !== '',
});
},
{injector: TestBed.inject(Injector)},
);
const submitSpy = jasmine.createSpy('submit');
await submit(f.first, (form) => {
submitSpy(form().value());
return Promise.resolve(customError({kind: 'lastName'}));
});
expect(submitSpy).toHaveBeenCalledWith('meow');
});
it('recovers from errors thrown by submit action', async () => {
const f = form(signal(0), {injector: TestBed.inject(Injector)});
expect(f().submitting()).toBe(false);
const {promise, reject} = promiseWithResolvers<ValidationError[]>();
const submitPromise = submit(f, () => promise);
expect(f().submitting()).toBe(true);
const error = new Error('submit failed');
reject(error);
await expectAsync(submitPromise).toBeRejectedWith(error);
expect(f().submitting()).toBe(false);
});
it('errors are cleared on edit', async () => {
const data = signal({first: '', last: ''});
const f = form(data, {injector: TestBed.inject(Injector)});
await submit(f, async (form) => {
return [
customError({kind: 'submit', field: f.first}),
customError({kind: 'submit', field: f.last}),
];
});
expect(f.first().errors()).toEqual([customError({kind: 'submit', field: f.first})]);
expect(f.last().errors()).toEqual([customError({kind: 'submit', field: f.last})]);
f.first().value.set('Hello');
expect(f.first().errors()).toEqual([]);
expect(f.last().errors()).toEqual([customError({kind: 'submit', field: f.last})]);
});
});
/**
* Replace with `Promise.withResolvers()` once it's available.
*
* See https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise/withResolvers.
*/
function promiseWithResolvers<T>(): {
promise: Promise<T>;
resolve: (value: T | PromiseLike<T>) => void;
reject: (reason?: any) => void;
} {
let resolve!: (value: T | PromiseLike<T>) => void;
let reject!: (reason?: any) => void;
const promise = new Promise<T>((res, rej) => {
resolve = res;
reject = rej;
});
return {promise, resolve, reject};
}