rsnext/test
stefanprobst 6b4b037396
chore: shorten image blur svg placholder (#38157)
trying to shorten the svg blur placeholder on `next/future/image`:

- is the `xlink` namespace needed?
- are self-closing tags allowed?

## Bug

- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have helpful link attached, see `contributing.md`

## Feature

- [ ] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have helpful link attached, see `contributing.md`

## Documentation / Examples

- [ ] Make sure the linting passes by running `pnpm lint`
- [ ] The examples guidelines are followed from [our contributing doc](https://github.com/vercel/next.js/blob/canary/contributing.md#adding-examples)
2022-07-06 15:34:24 +00:00
..
.stats-app Add middleware size stats (#37519) 2022-06-07 17:05:48 +00:00
__mocks__ Use Edge Runtime for running Edge Functions locally (#37024) 2022-05-30 12:01:36 +00:00
development Display stack trace when error occurs in API route (#38289) 2022-07-05 21:33:58 +00:00
e2e Fix global CSS file imports (#38339) 2022-07-05 23:07:13 +00:00
integration chore: shorten image blur svg placholder (#38157) 2022-07-06 15:34:24 +00:00
lib Alias react and react-dom by default (#38245) 2022-07-01 23:57:45 +00:00
production [build] validate the exported config values (#38370) 2022-07-06 11:06:57 +00:00
unit Adds tests to ensure eslint-plugin-next's available rules are properly exported and recommended rules are correctly defined. (#38183) 2022-06-30 11:31:33 -05:00
.gitignore
jest-setup-after-env.ts Adds tests to ensure eslint-plugin-next's available rules are properly exported and recommended rules are correctly defined. (#38183) 2022-06-30 11:31:33 -05:00
jest.d.ts Adds tests to ensure eslint-plugin-next's available rules are properly exported and recommended rules are correctly defined. (#38183) 2022-06-30 11:31:33 -05:00
readme.md Add handling for testing against deployments (#36285) 2022-04-20 12:23:09 +00:00
test-file.txt Add additional file serving tests (#12479) 2020-05-04 11:58:19 -05:00

Writing tests for Next.js

Getting Started

You can set-up a new test using yarn new-test which will start from a template related to the test type.

Test Types in Next.js

  • e2e: These tests will run against next dev, next start, and deployed to Vercel
  • development: These tests only run against next dev
  • production: These tests will run against next start.
  • integration: These tests run misc checks and modes and is where tests used to be added before we added more specific folders. Ideally we don't add new test suites here as tests here are not isolated from the monorepo.
  • unit: These are very fast tests that should run without a browser or running next and should be testing a specific utility.

For the e2e, production, and development tests the createNext utility should be used and an example is available here. This creates an isolated Next.js install to ensure nothing in the monorepo is relied on accidentally causing incorrect tests.

All new test suites should be written in TypeScript either .ts (or .tsx for unit tests). This will help ensure we catch smaller issues in tests that could cause flakey or incorrect tests.

If a test suite already exists that relates closely to the item being tested (e.g. hash navigation relates to existing navigation test suites) the new checks can be added in the existing test suite.

Best Practices

  • When checking for a condition that might take time, ensure it is waited for either using the browser waitForElement or using the check util in next-test-utils.
  • When applying a fix, ensure the test fails without the fix. This makes sure the test will properly catch regressions.