prototype using c8 as a test coverage lib; try alternatives to tape-runner

[siosonel]

Description

Work-in-progress. Puppeteer seems like an excellent replacement for tape-run, and has built-in code coverage API the can generate nyc/istanbul-compatible output.

To test:

# in sjpp dir
npm i c8 -g # install globally for now, can track in `package.json` later if everything works out

npm i puppeteer --save-dev --workspace=proteinpaint/client
npm i puppeteer-to-istanbul --save-dev --workspace=proteinpaint/client
# may not need the tls reject option below
NODE_TLS_REJECT_UNAUTHORIZED=0 npx puppeteer browsers install chrome

# must have a running server for puppeteer test
npm run dev

• in server dir, npm run test:unit, should see test coverage report like in the screenshot below
• in client dir, npm run test:puppet, must have selenium-webdriver installed globally or in parent repo (like sjpp). The terminal logs should be the same as in a desktop browser console, when running the same tests

TODOs:

• (DONE) generate test coverage report in browser environments (both desktop and headless)
• add more configurations to include code files without a spec file, maybe add include/exclude filters
• coverage report for client/dist chunk named files should use source-map file names, not chunk names
• must run each spec file separately, and filter by matching filename pattern, to get accurate coverage results
• have a PR-triggered CI to include coverage test requirements for changed files and line numbers (quicker), and a separate periodic CI action for coverage test across all files (takes longer to finish running)

Notes:

• nyc/istanbul instrumentation lib does not seem to support esm import syntax, only cjs require(), so any imported code/spec files are not instrumented for coverage, as being reached during test execution
• c8 uses V8-coverage, which uses the native coverage/profiler lib in V8 - the engine used by both Chrome browser and nodejs
• The checking coverage readme section has command line options like c8 check-coverage --lines 95 --functions 95 --branches 95
• for browser using testrun.html, may use Chrome Profiler from https://v8.dev/blog/javascript-code-coverage (not sure about this yet) EDIT: use puppeteer with istanbul

Screenshot of server unit test coverage, also logged in github unit test actions for this PR

Screenshot of client unit test coverage using puppeteer

Checklist

Check each task that has been performed or verified to be not applicable.

• Tests: added and/or passed unit and integration tests, or N/A
• Todos: commented or documented, or N/A
• Notable Changes: updated release.txt, prefixed a commit message with "fix:" or "feat:", added to an internal tracking document, or N/A