diff options
Diffstat (limited to 'docs/guides/test')
-rw-r--r-- | docs/guides/test/happy-dom.md | 2 | ||||
-rw-r--r-- | docs/guides/test/migrate-from-jest.md | 112 |
2 files changed, 113 insertions, 1 deletions
diff --git a/docs/guides/test/happy-dom.md b/docs/guides/test/happy-dom.md index 9c6728f88..072790929 100644 --- a/docs/guides/test/happy-dom.md +++ b/docs/guides/test/happy-dom.md @@ -49,7 +49,7 @@ test("set button text", () => { --- -With Happy DOM propertly configured, this test runs as expected. +With Happy DOM properly configured, this test runs as expected. ```sh $ bun test diff --git a/docs/guides/test/migrate-from-jest.md b/docs/guides/test/migrate-from-jest.md new file mode 100644 index 000000000..595ac0fae --- /dev/null +++ b/docs/guides/test/migrate-from-jest.md @@ -0,0 +1,112 @@ +--- +name: Migrate from Jest to Bun's test runner +--- + +In many cases, Bun's test runner can run Jest test suites with no code changes. Just run `bun test` instead of `npx jest`, `yarn test`, etc. + +```sh-diff +- $ npx jest +- $ yarn test ++ $ bun test +``` + +--- + +There's often no need for code changes. + +- Bun internally re-writes imports from `@jest/globals` to use the `bun:test` equivalents. +- If you're relying on Jest to inject `test`, `expect`, etc. as globals, Bun does that too. + +But if you'd rather switch to the `bun:test` imports, you can do that too. + +```ts-diff +- import {test, expect} from "@jest/globals"; ++ import {test, expect} from "bun:test"; +``` + +--- + +Bun implements the vast majority of Jest's matchers, but compatibility isn't 100% yet. Refer to the full compatibility table at [Docs > Test runner > Writing tests](/docs/test/writing#matchers). + +Some notable missing features: + +- `expect.extend()` +- `expect().toMatchInlineSnapshot()` +- `expect().toHaveBeenCalledWith()` +- `expect().toHaveReturned()` + +--- + +If you're using `testEnvironment: "jsdom"` to run your tests in a browser-like environment, you should follow the [DOM testing with Bun and happy-dom](/guides/test/happy-dom) guide to inject browser APIs into the global scope. This guide relies on [`happy-dom`](https://github.com/capricorn86/happy-dom), which is a leaner and faster alternative to [`jsdom`](https://github.com/jsdom/jsdom). + +At the moment jsdom does not work in Bun due to its internal use of V8 APIs. Track support for it [here](https://github.com/oven-sh/bun/issues/3554). + +```toml#bunfig.toml +[test] +preload = ["./happy-dom.ts"] +``` + +--- + +Replace `bail` in your Jest config with the `--bail` CLI flag. + +<!-- ```ts-diff +- import type {Config} from 'jest'; +- +- const config: Config = { +- bail: 3 +- }; +``` --> + +```sh-diff +$ bun test --bail 3 +``` + +--- + +Replace `collectCoverage` with the `--coverage` CLI flag. + +<!-- ```ts-diff +- import type {Config} from 'jest'; +- +- const config: Config = { +- collectCoverageFrom: [ +- '**/*.{js,jsx}', +- '!**/node_modules/**', +- '!**/vendor/**', +- ], +- }; +``` --> + +```sh +$ bun test --coverage +``` + +--- + +Replace `testTimeout` with the `--test-timeout` CLI flag. + +```sh +$ bun test --timeout 10000 +``` + +--- + +Many other flags become irrelevant or obsolete when using `bun test`. + +- `transform` — Buns supports TypeScript & JSX. Other file types can be configured with [Plugins](/docs/runtime/plugins). +- `extensionsToTreatAsEsm` +- `haste` — Bun uses it's own internal source maps +- `watchman`, `watchPlugins`, `watchPathIgnorePatterns` — use `--watch` to run tests in watch mode +- `verbose` — set `logLevel: "debug"` in [`bunfig.toml`](/docs/runtime/configuration.md#runtime) + +--- + +Settings that aren't mentioned here are not supported or have no equivalent. Please [file a feature request](https://github.com/oven-sh/bun) if something important is missing. + +--- + +See also: + +- [Mark a test as a todo](/guides/test/todo-tests) +- [Docs > Test runner > Writing tests](/docs/test/writing) |