fix(test): close leaked fetch contexts and OAuth callback timers to stop suite hang

[tripodsan]

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Related Issues

N/A — found while investigating a reported hang at the end of npm test.

Summary

npm test (c8 mocha) ran all tests successfully but the process kept running for several extra minutes after mocha reported the final "passing" summary, before finally exiting. Root cause: multiple leaked async resources kept the Node event loop alive.

1. Leaked @adobe/fetch keep-alive contexts

   • getFetch() in src/fetch-utils.js lazily creates and caches a keepAlive() fetch context (an open-socket connection pool). Production code paths always call resetContext() on shutdown, but no test ever did, so the shared context (used across test/server.test.js, test/up-cmd.test.js, test/utils.js) stayed open for the whole run.
   • An ad-hoc h1NoCache() context created per-request inside the http-proxy test in test/server.test.js was never reset.
   • A module-level h1NoCache() context in test/import-cmd.test.js was never reset.

2. Leaked OAuth callback timer

   • waitForToken() in src/content/da-auth.js starts a real 5-minute setTimeout safety timer that is only cleared once a /token callback request arrives on its local HTTP server.
   • Several tests in test/content/da-auth.test.js mocked that HTTP server as a no-op (or raced the real flow against an uncancelled 100ms timeout via Promise.race), so the callback never fired and the 5-minute timer kept running in the background — exactly matching the observed multi-minute delay before process exit.

Fix

• test/setup-env.js: added a global mochaHooks.afterAll hook that calls resetContext() to close the shared getFetch() context after the whole suite runs.
• test/server.test.js: reuse a single h1NoCache() context for the http-proxy test and reset() it in the finally block.
• test/import-cmd.test.js: reset() the module-level fetch context in an after() hook.
• test/content/da-auth.test.js: mock the HTTP callback server to simulate an immediate /token success response so waitForToken() resolves and clears its timer deterministically, instead of leaking it for up to 5 minutes. Removed the now-unnecessary Promise.race/timeout workaround.

Verification

• npx mocha and npm test (c8 mocha) both now exit on their own immediately after reporting results (548 passing), instead of hanging for several extra minutes.
• Confirmed via process._getActiveHandles() / timer-tracing instrumentation inside the actual mocha worker process that all previously-leaked sockets/timers are now properly closed/cleared.
• npx eslint passes on all changed files.

Thanks for contributing!