cross-bdd

Cross-runtime testing helpers that map to the native test runners in Bun, Deno, and Node.js so your specs can stay portable.

Why?

Every runtime ships its own standard library test runner with slightly different semantics. cross-bdd gives you a single describe/it pair that forwards to the familiar primitives in each environment, letting you share the same test suite without wrapping everything yourself.

Installation

npm add -D cross-bdd
# or
pnpm add -D cross-bdd
# or
yarn add -D cross-bdd
# or
bun add -d cross-bdd
# or
deno add npm:cross-bdd

Usage

// foo.test.ts

import { describe, it } from 'cross-bdd'

describe('math', () => {
  it('adds numbers', () => {
    const result = 2 + 2
    if (result !== 4) {
      throw new Error('Expected 4')
    }
  })

  it('supports async work', async () => {
    await new Promise((resolve) => setTimeout(resolve, 10))
  })
})

Then run your tests with the native test runner for your runtime:

# Bun
bun test
# Deno
deno test
# Node.js
node --test

Notes

• Can be used with @std/assert or @std/expect for runtime-agnostic assertions.

• You can nest describe blocks as needed. Async describe bodies are supported.

• An opinionated reusable workflow is provided in the repo. To use it, create a workflow file in your own repo:

  # .github/workflows/test.yaml
  name: Test
  
  on:
    push:
      branches: [main]
    pull_request:
      branches: [main]
      types: [opened, synchronize, reopened]
    workflow_dispatch:
  
  concurrency:
    group: ${{ github.workflow }}-${{ github.ref }}
    cancel-in-progress: true
  
  jobs:
    test:
      uses: brc-dd/cross-bdd/.github/workflows/test.reusable.yaml@main
      with:
        deno_versions: stable # remove this line to skip Deno testing
        bun_versions: latest # remove this line to skip Bun testing
        node_versions: 20 22 24 # remove this line to skip Node.js testing

Credits

Takes inspiration from cross-org/test, cross-org/workflows, and @std/testing/bdd.

Sponsors