Testing

@stratal/inertia/testing augments the TestResponse object with assertion methods for verifying Inertia pages, props, flash data, and precognition responses.

Setup

Import the testing side-effect in your test files or global setup:

import '@stratal/inertia/testing'

Assertion methods

Once the testing module is imported, the following methods are available on every TestResponse:

Method	Description
`assertInertia(callback?)`	Assert the response is an Inertia page. Optionally pass a callback to inspect the page object.
`assertInertiaComponent(name)`	Assert the rendered component matches the given name.
`assertInertiaProp(path, expected)`	Assert a prop value at the given path. Supports dot notation.
`assertInertiaPropExists(path)`	Assert a prop exists at the given path.
`assertInertiaPropMissing(path)`	Assert a prop does not exist at the given path.
`assertInertiaUrl(url)`	Assert the page URL matches the given string.
`assertInertiaVersion(version)`	Assert the asset version matches the given string.
`assertInertiaFlash(key, value)`	Assert flash data contains the given key and value.
`assertInertiaDeferredProp(prop, group)`	Assert a deferred prop exists and belongs to the given group.
`assertInertiaMergeProp(prop)`	Assert a prop is marked as mergeable.
`assertInertiaSharedProp(prop)`	Assert a shared prop is present on the page.
`assertSuccessfulPrecognition()`	Assert the response is a successful precognition response (204 status).
`assertPrecognitionValidationErrors(errors?)`	Assert the response contains precognition validation errors (422 status). Optionally verify specific error fields.

Example: testing a page render

import { Test } from '@stratal/testing'
import '@stratal/inertia/testing'
import { PostsModule } from '../src/posts.module'

describe('PostsController', () => {
  it('renders the index page', async () => {
    const module = await Test.createTestingModule({
      imports: [PostsModule],
    }).compile()

    const client = module.createHttpClient()
    const response = await client.get('/posts')

    await response
      .assertInertia()
      .assertInertiaComponent('posts/Index')
      .assertInertiaPropExists('posts')
  })
})

Example: testing flash data and validation

import { Test } from '@stratal/testing'
import '@stratal/inertia/testing'
import { PostsModule } from '../src/posts.module'

describe('PostsController', () => {
  it('validates post creation', async () => {
    const module = await Test.createTestingModule({
      imports: [PostsModule],
    }).compile()

    const client = module.createHttpClient()
    const response = await client.post('/posts', { body: {} })

    await response
      .assertInertiaFlash('errors', {
        title: expect.any(String),
      })
  })
})

Example: testing precognition

Precognition lets you validate form data before submission. Use the precognition assertions to verify that your validation rules work correctly:

it('validates with precognition', async () => {
  const module = await Test.createTestingModule({
    imports: [PostsModule],
  }).compile()

  const client = module.createHttpClient()

  const valid = await client.post('/posts', {
    headers: { 'Precognition': 'true' },
    body: { title: 'My Post', content: 'Hello world' },
  })
  await valid.assertSuccessfulPrecognition()

  const invalid = await client.post('/posts', {
    headers: { 'Precognition': 'true' },
    body: {},
  })
  await invalid.assertPrecognitionValidationErrors({
    title: expect.any(String),
  })
})