Testing

Test patterns, commands, and utilities for the Meteor codebase.

Test Commands

CLI self-tests

./meteor self-test # Run all CLI tests ./meteor self-test "test name" # Run specific test ./meteor self-test --list # List available tests ./meteor self-test --exclude "^[a-b]" # Exclude tests by regex ./meteor self-test --retries 0 # Skip retries in development

Package tests (TinyTest — view results at http://localhost:3000)

./meteor test-packages # Test all core packages ./meteor test-packages mongo # Test specific package TINYTEST_FILTER="collection" ./meteor test-packages # Filter specific tests

Package tests in console (headless via Puppeteer)

PUPPETEER_DOWNLOAD_PATH=~/.npm/chromium ./packages/test-in-console/run.sh

Modern E2E tests (Jest + Playwright)

npm run install:modern # Install dependencies npm run test:modern # Run all E2E tests npm run test:modern -- -t="React" # Run specific test

Modern E2E Tests (tools/modern-tests/ )

Jest + Playwright suite for verifying modern bundler integrations (rspack). Tests cover framework skeletons and build scenarios.

Test apps: apps/{react,vue,svelte,solid,blaze,typescript,babel,coffeescript,monorepo}

Test Helpers Package (packages/test-helpers )

Comprehensive testing utilities for Meteor applications.

Async Testing

import { testAsyncMulti, simplePoll, waitUntil } from 'meteor/test-helpers';

// Wait for condition await waitUntil(() => someCondition, { timeout: 5000, interval: 100 });

// Poll until ready simplePoll(() => isReady(), successCallback, failCallback);

DOM/UI Testing

import { clickElement, simulateEvent, canonicalizeHtml, renderToDiv } from 'meteor/test-helpers';

clickElement(button); simulateEvent(input, 'keydown', { keyCode: 13 }); const normalized = canonicalizeHtml(html);

Connection Testing

import { makeTestConnection, captureConnectionMessages } from 'meteor/test-helpers';

const conn = makeTestConnection(clientId); const messages = captureConnectionMessages(server);

Utilities

Function Description

SeededRandom

Predictable random for deterministic tests

try_all_permutations()

Test all permutations of inputs

withCallbackLogger()

Track callback invocations

mockBehaviours()

Behavior mocking

Tinytest (packages/tinytest )

Meteor's built-in test framework.

Tinytest.add('my test', function (test) { test.equal(1 + 1, 2); test.isTrue(true); test.throws(function () { throw new Error(); }); });

Tinytest.addAsync('async test', async function (test) { const result = await asyncOperation(); test.equal(result, expected); });

Environment Variables

Variable Description

TEST_METADATA

Test configuration JSON

METEOR_TEST_PACKAGES

Packages to test

Debug Commands

Verbose build output

METEOR_DEBUG_BUILD=1 ./meteor run

Profile build performance

METEOR_PROFILE=1 ./meteor build

Force rebuild

./meteor reset && ./meteor run

Debug Meteor tool with Chrome inspector

TOOL_NODE_FLAGS="--inspect-brk" ./meteor

Writing Package Tests

In package.js :

Package.onTest(function(api) { api.use(['tinytest', 'test-helpers', 'my-package']); api.addFiles('my-package-tests.js'); });

In my-package-tests.js :

import { MyPackage } from 'meteor/my-package';

Tinytest.add('MyPackage - basic functionality', function (test) { const result = MyPackage.doSomething(); test.equal(result, expected); });