test(cli): pin behavior for malformed .svelte files in both passes

[oekazuma]

Summary

Characterization tests only — no behavior change. svelte-vitals handles syntactically broken .svelte files asymmetrically across its two passes, and neither behavior was pinned by a test:

• Component pass (collectComponentFacts): a parse/read failure is swallowed and the file contributes empty facts — analysis continues for the rest of the project.
• Route pass (resolveRoute): no try/catch — one broken +page.svelte/+layout.svelte aborts the entire analysis with exit 2.

This PR pins both behaviors (including the asymmetry) as an intentional contract, so future refactors — notably the planned per-run parse cache — cannot change them unnoticed, and so the hand-maintained empty-facts fallback shape is caught by a strict toEqual when ComponentFacts gains a field.

Tests added (packages/cli/test/malformed-svelte.test.ts)

1. A broken $lib component yields exact empty facts while the well-formed sibling route file is still parsed normally
2. run() on a project with a broken component completes with exit 0/1 — never 2
3. An unreadable file (readFile rejects) takes the same fallback, exercised via an in-memory Runtime
4. A broken route file makes run() exit 2 with a svelte-vitals: error — commented as a known, currently-intentional asymmetry that must be updated deliberately, not silenced

Two new fixtures: malformed-component-project/, malformed-route-project/.

Note

The intentionally-invalid fixtures had to be added to .prettierignore (prettier-plugin-svelte cannot parse them), mirroring the existing eslint fixture exclusion.

Verification

• pnpm typecheck / pnpm lint — clean
• pnpm test — 719 tests pass across all packages (cli 288 incl. the 4 new)
• No changeset (test-only change)

🤖 Generated with Claude Code

Summary by CodeRabbit

• Bug Fixes

  • Improved handling of malformed Svelte files so valid files can still be processed when nearby fixtures contain syntax errors or are unreadable.
  • Route checks now fail cleanly with a clear error when a page component cannot be parsed, instead of producing inconsistent results.

• Tests

  • Added coverage for malformed component and route scenarios to verify parsing, file-read failures, and error reporting.

[coderabbitai]

📝 Walkthrough

Walkthrough

This PR adds two fixture Svelte projects (component and route paths) containing intentionally malformed, unclosed template syntax, updates .prettierignore to exclude these fixtures from formatting, and introduces a Vitest suite validating that parsing failures are handled gracefully without crashing.

Changes

Malformed Svelte fixtures and parser-failure tests

Layer / File(s)	Summary
Malformed fixture projects .prettierignore, packages/cli/test/fixtures/malformed-component-project/*, packages/cli/test/fixtures/malformed-route-project/*	Adds two fixture projects with package.json metadata and Svelte files containing unclosed {#if} blocks; excludes these fixture directories from Prettier formatting.
Parser-failure test suite packages/cli/test/malformed-svelte.test.ts	Adds tests verifying collectComponentFacts returns empty facts (rather than throwing) on parse errors or unreadable files while other files still parse correctly, and that run() exits with code 2 and logs an error when a route file is malformed.

Estimated code review effort: 2 (Simple) | ~12 minutes

Possibly related PRs

• oekazuma/svelte-vitals#112: Overlaps with this PR's fixture/test coverage of parse and read failures, related to parseComponentFacts refactor behavior for handling malformed input.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately summarizes the PR’s main change: characterization tests pinning malformed .svelte behavior in both analysis passes.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch advisor/002-malformed-svelte-characterization

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands.}

[coderabbitai]

🧹 Nitpick comments (1)

packages/cli/test/malformed-svelte.test.ts (1)

38-50: 📐 Maintainability & Code Quality | 🔵 Trivial | 💤 Low value

Optional: extract the shared "empty facts" fixture.

The expected empty-facts object is duplicated verbatim between the two tests. A small shared constant would reduce duplication and keep both assertions in sync if the shape in components.ts changes.

♻️ Proposed consolidation

+const EMPTY_FACTS = {
+  eachBlocks: [],
+  effects: [],
+  htmlTags: [],
+  javascriptUrls: [],
+  loc: 0,
+  propCount: 0,
+  imports: [],
+  namespaceImports: [],
+  constableStates: [],
+  suppressions: []
+};
+
 describe('collectComponentFacts: malformed .svelte files (component path)', () => {
   ...
-    expect(broken).toEqual({
-      file: 'src/lib/Broken.svelte',
-      eachBlocks: [],
-      ...
-    });
+    expect(broken).toEqual({ file: 'src/lib/Broken.svelte', ...EMPTY_FACTS });

Also applies to: 94-106

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@packages/cli/test/malformed-svelte.test.ts` around lines 38 - 50, The
empty-facts expectation is duplicated across the malformed Svelte tests, so
extract it into a shared fixture constant and reuse it in both assertions.
Update the tests around the broken/empty facts checks to reference the shared
object instead of inlining the same shape, keeping the fixture aligned with the
expected structure from components.ts.

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Nitpick comments:
In `@packages/cli/test/malformed-svelte.test.ts`:
- Around line 38-50: The empty-facts expectation is duplicated across the
malformed Svelte tests, so extract it into a shared fixture constant and reuse
it in both assertions. Update the tests around the broken/empty facts checks to
reference the shared object instead of inlining the same shape, keeping the
fixture aligned with the expected structure from components.ts.

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 00d77c0c-0965-45c6-8522-b4d4bb1979c5

📥 Commits

Reviewing files that changed from the base of the PR and between e6747ec and f7f22c2.

📒 Files selected for processing (7)

• .prettierignore
• packages/cli/test/fixtures/malformed-component-project/package.json
• packages/cli/test/fixtures/malformed-component-project/src/lib/Broken.svelte
• packages/cli/test/fixtures/malformed-component-project/src/routes/+page.svelte
• packages/cli/test/fixtures/malformed-route-project/package.json
• packages/cli/test/fixtures/malformed-route-project/src/routes/+page.svelte
• packages/cli/test/malformed-svelte.test.ts