fix: don't fail tarball bundling on modules that don't exist if they are optional or caught

[pieh]

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Summary

Fixes https://linear.app/netlify/issue/FRB-2118/bundling-fails-on-caught-missing-dynamic-import

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No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: 67a9f1be-b99c-4fe9-b36a-fa578c29cf72

📥 Commits

Reviewing files that changed from the base of the PR and between a92d700 and 87cadf9.

📒 Files selected for processing (1)

• packages/edge-bundler/node/bundler.test.ts

🚧 Files skipped from review as they are similar to previous changes (1)

• packages/edge-bundler/node/bundler.test.ts

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📝 Walkthrough

Summary by CodeRabbit

• Bug Fixes

  • Fixed an issue where the bundler would incorrectly track and report unresolved module dependencies when edge functions attempted to import non-existent modules within try/catch blocks, causing bundling errors even when imports were gracefully handled.

• Tests

  • Added comprehensive test coverage validating correct bundler behavior when edge functions gracefully handle non-existent module imports during initialization.

Walkthrough

The tarball bundler now avoids including local file:// module paths in getRequiredSourceFiles when those modules have a "Module not found" error. A new fixture edge function attempts a dynamic import of a nonexistent module inside a try/catch and returns a response. A test was added that runs the bundler with tarball output, asserts no dependency-tracking error was logged, verifies manifest.json includes bundling_timing.tarball_ms, checks tarball contents, and executes both the tarball and eszip artifacts; it calls cleanup() after running.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~12 minutes

🚥 Pre-merge checks | ✅ 1 | ❌ 2

❌ Failed checks (1 warning, 1 inconclusive)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 50.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.
Description check	❓ Inconclusive	The description includes a reference to the linear issue (FRB-2118) but lacks explanations of motivation and how the fix solves the problem.	Add a detailed explanation of the motivation and how the fix prevents bundling failures for optional or caught missing dynamic imports.

✅ Passed checks (1 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly describes the main change: preventing tarball bundling failures for modules that don't exist when they are optional or caught.

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• Commit unit tests in branch michalpiechowiak/frb-2118-bundling-fails-on-caught-missing-dynamic-import

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[pieh]

If this was critical error that prevents code to run - we wouldn't get to this point and would crash hard at Inline Config extraction which does load the bundle and return config export.

So if we get here and we get Module not found errored modules in module graph - this should be case of optional modules (try/catch) OR "virtual" modules (like Next.js Node middleware setup before workaround applied in opennextjs/opennextjs-netlify#3448 )

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Actionable comments posted: 1

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Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@packages/edge-bundler/node/bundler.test.ts`:
- Around line 1268-1272: The test passes extra optional options that reference
non-existent files—remove the configPath and importMapPaths entries from the
bundle(...) call in bundler.test.ts so the test only provides basePath,
featureFlags, and declarations; specifically edit the bundle invocation (the
call to bundle([...], distPath, declarations, {...})) to delete the configPath
and importMapPaths properties and leave the rest unchanged.

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: f723daad-ef3f-4584-aadd-d5f57f454e29

📥 Commits

Reviewing files that changed from the base of the PR and between 238ed96 and a92d700.

📒 Files selected for processing (3)

• packages/edge-bundler/node/bundler.test.ts
• packages/edge-bundler/node/formats/tarball.ts
• packages/edge-bundler/test/fixtures/caught-module-not-found-import/netlify/edge-functions/func1.ts