yarn test:mediabunny runs historical lifecycle observations, candidate load cancellation, and real SDK input parsing/track contracts; all are in test:unit. Candidate failures can be reproduced against the frozen main with ARTPLAYER_MB_BASELINE=1. This does not replace native playback or installed consumers. See refactor/mb-validation.md and the proxy package's ARCHITECTURE.md for browser and artifact selection.

yarn test:ads runs source, verified npm 1.0.6 and the frozen unpublished 2.1.0 Ads bundle against controlled clock/host contracts. It is included in test:unit. The helper uses the real option validator but does not simulate media decoding or layout. Historical defect assertions apply only to frozen implementations. See Ads validation for artifact overrides and browser scope. ads-lifecycle.test.js adds candidate-only resource, reentry, early-method and Promise regressions. Async observations drain one event-loop turn, including VM Promise assimilation, rather than assuming a fixed number of microtasks. The published defect observations stay intact.

Command	Scope
`yarn test:unit`	Playback and DASH regressions, public contracts against released/current code, and JS/TS fixture loading
`yarn test:node`	Unit contracts plus toolchain and documentation build failure propagation
`yarn test:ci`	Actual CI summary exit codes, workflow regression guards and repository impact analysis
`yarn test`	Node checks and the committed baseline/tooling tests in refactor/scripts
`yarn ci:check`	Toolchain, plan, read-only lint, types, then yarn test
`yarn test:imports`	Existing distribution import smoke examples; run after building

helpers/load.js owns source and artifact selection. loadModules bundles named internal modules with esbuild and requires exactly one JS/TS source file. loadPackage uses the repository Vite configuration without writing distribution files; it requires a single self-contained JavaScript chunk. These loaders transpile but do not replace yarn typecheck.

helpers/playback.js creates the controlled media facade used by the original playback regressions. It models only the exercised methods and events. It is not HTMLMediaElement validation; actual playback remains in browser tests.

node --test test/hls-control.test.js runs shared HLS control contracts against workspace source and integrity-checked published main/legacy/ESM. It is included in yarn test:unit. helpers/hls-control.js owns the controlled SDK/registry host; it does not simulate decoding or ABR. Published-only tests preserve historical bug observations without requiring candidate code to keep them. Real Hls.js 1.5.17 playback is in test/browser/hls-control.spec.js; see its environment limits in refactor/hls-validation.md. Test SDK download is pinned and verified, not an installed runtime dependency.

contracts/emitter.js owns public assertions, independent of module layout. public-behavior.test.js runs them against the integrity-checked published core and current bundled source. The combined chain/context contract corresponds to BASE-03 EVENT.chain and EVENT.context-arguments; other EVENT IDs retain their baseline names. Exceptions, callback identity, mutation during dispatch and once reentry must not be weakened during migration.

Set ARTPLAYER_TEST_CORE to a built .js, .legacy.js or .mjs core file to add a candidate to the same public-contract run, then execute node --test test/public-behavior.test.js. An invalid path/export fails the run. This is a narrow event contract check, not isolated package installation or complete API compatibility; ENG-07 owns tarball consumption.

When a production module moves, update its loader mapping and its maintenance documentation, preserving the behavioral assertions. New contracts belong in contracts/; test-specific controlled state belongs in helpers/. Do not modify frozen refactor/fixtures or baseline captures just to pass changed behavior. Record historical defects and candidate fixes separately.

ci-summary.test.js exercises the real CLI with success, cancelled and malformed provider data, plus missing groups and metadata/environment files. It is included in test:node. refactor/scripts/ci-workflow.test.mjs parses the actual YAML and rejects broken matrix, cache, install, report and summary requirements; it is included in test:baseline. These local tests do not replace hosted runner or branch-protection evidence. See CI operations before changing a required job or its cache.

Real browser tests

test/utils.test.js compares the published and current utilities, including exact formatting, subtitle text, property/merge behavior, controlled timers and the full utility export surface. It accepts the same ARTPLAYER_TEST_CORE option for all three artifact formats. The merge prototype fix is a candidate assertion alongside a published-only defect observation. test/types/utils-source.ts checks strict internal source inference without changing the still-separate public declaration contract. Browser utility tests exercise actual downloads, Blob URL contents and cleanup when a controlled click fails.

See browser/README.md for yarn test:browser, browser installation, published/current combinations, media fixtures, candidate mapping and failure reports. These tests are separate from the fast Node suite and run in the Browser playback smoke CI job.

test/audio-track.test.js compares source and published Audio Track 1.1.0 in all three formats with a controlled Audio object: timing intent, offsets, source updates, rejection, volume/rate, independent instances and cleanup. Published-only tests retain defect evidence. See audio validation for actual media tests and limitations.

Document PiP: yarn test:dpip runs 48 historical window/DOM/lifecycle cases. Native DOM iframe checks use yarn test:browser test/browser/dpip.spec.js; controlled window APIs do not establish native Document PiP support. See validation notes.