e2e-coverage

name	e2e-coverage
description	Use when adding, modifying, or reviewing E2E test apps/skeletons to keep the test coverage report up to date.

E2E Test Coverage Report

Guidelines for maintaining dev/modern-tools/rspack/E2E_COVERAGE.md — a single-page report of what every E2E app and skeleton tests.

When to Update

Trigger	Action
New app added to apps/	Add a subsection under Apps with a coverage table
New skeleton added to skeleton.test.js	Add a row to the Skeletons table
New npm package imported for compatibility testing	Add an entry under NPM Package Compatibility with the package name, file, and reason
New custom assertion added to a test file	Add a row to that app's coverage table
New feature tested across multiple apps	Add a row to the Feature Coverage Matrix
App or skeleton removed	Remove its entries from all sections

Report Structure

The report has five sections, in this order:

1. Test Lifecycle — the phases every app/skeleton goes through (init, run, prod, test, test once, build) and what default assertions apply
2. Apps — one subsection per apps/<name>/ with a short description and a | What is covered | Phase | table
3. Skeletons — single table with one row per skeleton (| Skeleton | Port | Language | Extra coverage |)
4. NPM Package Compatibility — grouped by app, each entry has the package name, file path, and why it's included (ESM-only, native bindings, subpath exports, etc.)
5. Feature Coverage Matrix — cross-reference table (| Feature | Apps | Skeletons |) showing where each capability is tested

How to Gather Information

For each app or skeleton, check these sources:

Source	What to look for
<name>.test.js	Test helper used, options (env, configFile, buildDir, testFullApp, checkBundleFilePaths), all customAssertions callbacks and what they assert
skeleton.test.js	The testMeteorSkeleton({ skeletonName: '<name>' }) block for that skeleton
apps/<name>/server/main.js	npm imports with comments explaining why (ESM-only, native bindings, etc.)
apps/<name>/imports/	Shared code with special imports (node: protocol, JSX packages)
apps/<name>/rspack.config.*	Custom config features (compileWithRspack, compileWithMeteor, disablePlugins, custom rules)
apps/<name>/package.json	Dependencies that exist solely for compatibility testing

Writing Guidelines

• Keep descriptions short — one line per table row
• Use the phase names from the lifecycle table: Init, Run, Prod, Test, Build, All
• For npm packages, always state the reason (what module format issue it validates)
• Don't duplicate info between the per-app table and the feature matrix — the app table has detail, the matrix has the cross-reference
• When an env var is set in a test file, note it as All (env prefix) in the phase column