Run one spec

Pick the suite the file belongs to. Do not start with npm test.

Isolation is below. Coverage is a separate full-suite run — see write-spec after a gated sources/ or scripts/ edit (skip if the path is in codecov.yml ignore:).

Node (tests/node/)

npm run test:node collects every *_spec.js / *_spec.ts and ignores extra args. Call node --test on the file instead:

node --test tests/node/scripts/generateSources/items_spec.ts
node --test --test-name-pattern="parseItem" tests/node/scripts/generateSources/items_spec.ts

npm run test:node:coverage also runs every Node spec, not this file alone.

Browser (Testem + Mocha)

tests/tests.js imports every browser spec. There is no CLI file filter. Do not comment out imports. A spec that is not imported never runs; Codecov patch then fails with no Mocha failure.

Filter with ?grep= (best isolation). Start the server, then open the harness with a grep pattern:

npm run test:server
# then open, in the launched browser:
# http://localhost:7357/tests_run.html?debug=false&grep=CategoryTree

Mocha's browser bundle reads grep, fgrep, and invert from location.search inside mocha.run(), which tests/tests.js calls. Every spec file is still imported, so the filter selects which tests execute, not which files load. The Mocha UI search box does the same thing by rewriting this query string.

If 7357 is busy, testem.cjs reads TESTEM_PORT:

TESTEM_PORT=7360 npm run test:server

it.only / describe.only works locally as a fallback. Do not commit it.

testem.cjs before_tests always runs every Node spec first, including this Chrome-only command. It is still the full Mocha browser suite, not one file:

node ./node_modules/testem/testem.js ci --launch Chrome

npm run test:browser:coverage is that full suite in Chrome and Firefox.

DEBUG=1 (or DEBUG=true) keeps the app's verbose debug output instead of the default ?debug=false.

Visual (Playwright)

npm run test:visual uses Playwright’s webServer (npm run dev locally). npx playwright test with this repo’s config does the same.

npx playwright test tests/visual/home.spec.js
npx playwright test -g "title substring"

Wait for catalog/canvas via tests/visual/home-helpers.ts. Do not register visual specs in tests/tests.js. They are not Codecov-instrumented. Argos upload needs ARGOS_TOKEN. When a change warrants a visual run: visual-test.