🧪 Testing utilities

Use Deno to perform cross-platform testing on the Deno, Node.js and Bun runtimes.

• 📚 Documentation

📑 Examples

// Because the testing module will spawn runtime processes, permissions are required to run tests.
// You also need to specify any additional permissions required by tests since permissions escalation is not permitted.
// deno test --allow-net=0.0.0.0 --allow-run=deno,bun,npx,node example.ts
import { expect, Status, test } from "./mod.ts"

// Test is performed on all available runtimes by default
// If a runtime is not available, the test is automatically skipped
test("all")("test on all available runtimes", () => {
  expect("https://example.com").toBeUrl()
})

// Test can be restricted to specific runtimes
test("node", "bun")("test only on node and bun runtimes", () => {
  expect("foo").toBeOneOf(["foo", "bar"])
})

// Test on deno are performed without any additional permissions by default
// to satisfy the principle of least privilege, but can be overridden (this is ignored on other runtimes)
// Additionally, everything specified in backticks in test names will be syntax highlighted
test("deno")("test `Deno.serve({ port: 8080 })` with additional `{ permissions: { net: 'inherit' } }`", async () => {
  await using server = Deno.serve({ port: 8080, onListen: () => null }, () => new Response(null, { status: Status.OK }))
  await expect(fetch(`http://${server.addr.hostname}:${server.addr.port}`)).resolves.toRespondWithStatus("2XX")
}, { permissions: { net: "inherit" } })

// You can also use `test.only` (alias to `Deno.test.only`), `test.skip` (alias to `Deno.test.ignore` with gray color),
// and `test.todo` (alias to `Deno.test.skip` with yellow color) to mark tests accordingly
test.todo("node")("todo test")
test.skip("node")("broken test", () => {
  throw new Error()
})

✨ Features

• Extends @std/expect with additional matchers (toMatchDescriptor, toBeImmutable, toBeIterable, toRespondWithStatus, toBeEmail, etc.)
  • See @libs/testing/expect for more information about available matchers.
• Specify which runtimes should be tested per test case
• Automatically detect which runtimes are available and skip tests accordingly for a streamlined development experience.
• Automatically install dependencies using deno info and the correct package manager for each runtime.
• The permissions for deno test are defaulted to "none" rather than "inherit".
• Syntax highlighting in test names for better readability.

[!WARNING] Although this library is designed for cross-platform testing, it must be run through Deno. Test cases will be spawned in subprocesses.

🤖 Workflow usage

Below is an example on how it could be used within a GitHub Actions workflow:

on:
  push:
  pull_request:

jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: denoland/setup-deno@v1
        with:
          deno-version: 1.x
      - uses: oven-sh/setup-bun@v1
        with:
          bun-version: 1.x
      - uses: actions/setup-node@v4
        with:
          node-version: 22.x
      - run: deno task ci

🕊️ Migrating from 2.x.x to 3.x.x

Version 3.x.x and onwards require Deno 2.x.x or later.

toBeType("object") and null

The toBeType("object") matcher now excludes null by default. The second argument has been replaced by an object with a nullable property for better readability.

- expect(null).toBeType("object", !null)
+ expect(null).toBeType("object", { nullable: true })

Updated headers and syntax highlighting

The prefix for runtime in test names has been changed to be displayed in uppercase over a colored background. If you were using the deno test --filter option, you will need to update your filter accordingly.

- [deno]
+  DENO

Additionally, test names now syntax highlight everything specified in backticks.

📜 License

Copyright (c) Simon Lecoq <@lowlighter>. (MIT License)
https://github.com/lowlighter/libs/blob/main/LICENSE