Restore Node.js test registration in ESM

[dahlia]

On 2.0-maintenance, @fedify/fixture swallows the missing require() error in ESM, so Node.js reports passing files without running their tests. This ports the createRequire() fix from fab1c07, removes the catch, and keeps Workers on its test-collection path without changing the maintenance branch's test API.

Regression tests load the built ESM/CJS exports in separate Node.js processes, so the adapter cannot silently skip its own tests. The newly running actor tests use public IP literals to avoid DNS lookups before mocked fetches, and await rejects() so failures reach the runner.

Affected Node/Deno/Bun suites, mise run check, and a local Workers smoke test pass. The full Node.js run still has unrelated ansi-escapes dependency failures in @fedify/init, @fedify/create, and @fedify/cli.

Fixes #1036.

[coderabbitai]

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ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Repository UI

Review profile: ASSERTIVE

Plan: Advanced

Run ID: 7c3b239f-ba6b-4e2a-aaf3-1c884d5c287b

📥 Commits

Reviewing files that changed from the base of the PR and between d863a12 and cd3a6cc.

📒 Files selected for processing (3)

• packages/fixture/src/test.test.ts
• packages/fixture/src/test.ts
• packages/vocab/src/actor.test.ts

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📝 Walkthrough

Walkthrough

The fixture harness now loads node:test only in supported Node environments. New probes cover ESM, CommonJS, failure behavior, ignored tests, registration errors, and Workers collection. The actor handle test uses IP-based WebFinger mocks and awaits its rejection assertion.

Changes

Fixture Node registration

Layer / File(s)	Summary
Guarded Node test loading packages/fixture/src/test.ts	The harness uses createRequire to load node:test when running on Node outside Cloudflare Workers. Other runtimes skip test execution and retain definitions in testDefinitions.
Fixture runtime probes packages/fixture/src/test.test.ts	Isolated ESM and CommonJS probes verify registration, execution, failure propagation, ignored callbacks, registration failures, and Workers collection.

WebFinger test stability

Layer / File(s)	Summary
WebFinger mock and assertion updates packages/vocab/src/actor.test.ts	WebFinger mocks use 1.1.1.1 and 8.8.8.8. Expected handles and actor identifiers use the new hosts. The no-WebFinger rejection assertion is awaited.

Priority: ➖ Normal

Estimated code review effort: 3 (Moderate) | ~25 minutes

Change: Bug fix · Severity of issue fixed: Medium

Sequence Diagram(s)

sequenceDiagram
  participant ProbeProcess
  participant FixtureHarness
  participant NodeTest
  participant TestDefinitions
  ProbeProcess->>FixtureHarness: Load fixture and register tests
  FixtureHarness->>NodeTest: Register tests in supported Node
  NodeTest-->>ProbeProcess: Emit test results and diagnostics
  FixtureHarness->>TestDefinitions: Collect definitions in Workers
  TestDefinitions-->>ProbeProcess: Expose collected definitions without execution

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Merge Risk: ⚪ Minimal · up to cd3a6

The Node registration fix preserves the supported Workers configuration and is ready to merge after normal checks.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 2 functions across 3 files.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly identifies the main change: restoring Node.js test registration for ESM builds.
Description check	✅ Passed	The description directly explains the Node.js ESM registration failure, the createRequire() fix, preserved Workers behavior, regression tests, and validation results.
Linked Issues check	✅ Passed	Issue #1036 requires Node.js registration for fixture tests, preserved Workers collection, preserved maintenance-branch API, and regression coverage. packages/fixture/src/test.ts now uses `createReq…
Out of Scope Changes check	✅ Passed	The actor-test changes use public IP literals and await rejects() so the newly active Node.js tests do not fail because of DNS resolution or an unobserved promise. These changes support the registra…

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ All tests successful. No failed tests found.
see 1 file with indirect coverage changes

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