Hotfix: bind fetch to globalThis to avoid 'Illegal invocation' - #9
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Storing the native browser fetch as a bare reference on an instance field (VaultClient.fetchImpl) or as a default parameter loses its Window receiver. At call time the browser sees `this !== Window` and throws TypeError: Failed to execute 'fetch' on 'Window': Illegal invocation. jsdom's fetch is permissive and didn't catch this. Bind `fetch` to `globalThis` in all four default paths (VaultClient constructor, discoverAuthServer, registerClient, beginOAuth, completeOAuth). Add a regression test that installs a this-aware fetch shim mimicking the browser's check — instantiates VaultClient without an explicit fetchImpl and confirms vaultInfo() resolves. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Summary
fetchrequiresthis === Window. Storing a barefetchreference onVaultClient.fetchImpl(or as a default param in oauth/discovery helpers) loses that binding — at call-timethisis the VaultClient instance and the browser throwsTypeError: Failed to execute 'fetch' on 'Window': Illegal invocation.fetchis permissive and didn't enforce the invariant, so existing tests passed while the browser broke.fetch.bind(globalThis)in all four default paths —VaultClientconstructor,discoverAuthServer,registerClient,beginOAuth,completeOAuth.this !== globalThis, instantiatesVaultClientwithout an explicitfetchImpl, and assertsvaultInfo()resolves. Verified it fails without the fix.Test plan
bun run lintcleanbun run typecheckcleanbun run test— 101 tests pass (new regression included)bun run buildsucceeds🤖 Generated with Claude Code