deno-test

1.0.2 verified Sat May 09 auth: no javascript

Run Deno-style tests (Deno.test, t.step) on Node.js without rewriting test files. v1.0.2 requires Node.js >=23.6.0 for its sync module hooks. Resolution uses @deno/loader to handle jsr:, @std/*, and import maps. Outputs results via node:test runner. Ideal for checking Node.js compatibility of Deno-first packages.

Common errors

error Cannot find module 'register-deno-hooks.mjs' required by 'deno-test' ↓

cause Node.js version < 23.6.0; module.registerHooks() not available

fix

Upgrade to Node.js >= 23.6.0

error TypeError: Deno.test is not a function ↓

cause Test file not loaded by deno-test CLI; trying to import directly in Node.js

fix

Run file with npx deno-test [file] instead of node

error Error: Unsupported file extension .ts for import map resolution ↓

cause Missing or misconfigured import map in deno.json

fix

Ensure deno.json exists at project root with correct 'imports'

error Test steps not executed: step callback must be async ↓

cause t.step called without await in async callback

fix

Use await t.step() inside async (t) => {}

Warnings

breaking Node.js >= 23.6.0 required (uses module.registerHooks()) ↓

fix Upgrade Node.js to 23.6.0 or later.

gotcha Import maps must be in deno.json; other config files are not supported ↓

fix Place import map in deno.json at project root.

gotcha Raw URL imports (https://deno.land/...) are not resolved; use jsr: or import map ↓

fix Use jsr:@scope/pkg or add to import map in deno.json.

deprecated Deno.test steps must be async callbacks; sync callbacks may cause unexpected results ↓

fix Always use async (t) => callback with await t.step().

gotcha Files in node_modules, .git, vendor are skipped automatically ↓

fix No fix needed; be aware of discovery scope.

breaking Supports only Deno.test and t.step; other Deno globals (e.g., Deno.readFile) are not available ↓

fix Polyfill missing Deno APIs separately or avoid them in tests.

gotcha Output uses node:test reporter; may differ from Deno's test output formatting ↓

fix Use --reporter flag of node:test if needed.

Install

npm install deno-test

yarn add deno-test

pnpm add deno-test

Imports

Deno.test
wrong
```
import { Deno } from 'deno-test';
```
correct
```
// no import needed; Deno.test is global when using deno-test CLI
```
Deno.test is globally injected via @deno/shim-deno-test when file is loaded by CLI.

assertEquals

wrong

import { assertEquals } from 'https://deno.land/std/assert/mod.ts';

correct

import { assertEquals } from '@std/assert';

Use jsr: specifiers or import map; raw URL imports not supported.

t.step

wrong

t.step('sub', () => {}); // missing await

correct

Deno.test('name', async (t) => { await t.step('sub', () => {}); });

t.step must be awaited; maps to node:test subtests.

register-deno-hooks

wrong

import 'deno-test/register-deno-hooks.mjs';

correct

// not imported; CLI handles automatically

The hooks module is internal; do not import directly.

Quickstart

Demonstrates writing a Deno-style test and running it on Node.js via npx.

// Create a test file: math_test.ts
import { assertEquals } from '@std/assert';

Deno.test('add', () => {
  assertEquals(1 + 1, 2);
});

// Run with npx deno-test (no extra config)
// Requires deno.json with import map referencing @std/assert
// > npx deno-test