Keep test-only source out of the published build

[timon0305]

Closes #217

The tsconfig exclude pointed at a stale path (src/server/tools/test-helpers.ts), but the file lives at src/core/server/tools/test-helpers.ts. Because the glob never matched, tsc compiled it into dist/. Scoping that out surfaced a second leak: config-branding.compile-test.ts also shipped, since its -test.ts name is not caught by **/*.test.ts.

What changed

Split the build config from the typecheck config. tsconfig.build.json excludes all test code by pattern (**/*.test.ts, **/*.compile-test.ts, **/test-helpers.ts, **/__tests__/**), so it stays correct if files move. The base tsconfig.json still type-checks the .compile-test.ts brand guards, which is their whole purpose. build and build:watch now run -p tsconfig.build.json.

Added a regression test that asks tsc which files the build config compiles (--listFilesOnly) and fails if any test module survives. It also asserts a real source file is present so it cannot pass on an empty program.

Verification

• Clean build: 50 source JS files, zero test artifacts in dist/.
• Typecheck still covers the compile-test guards.
• Lint, format:check, and the full suite (367 tests) pass.

Summary by CodeRabbit

• Build Improvements

  • Updated production builds to use a dedicated TypeScript build configuration and clean dist before compiling.
  • Ensured test-only files and development helpers are excluded from production build output.
  • Updated build watch mode to track the production build TypeScript configuration.

• Tests

  • Added an automated check that verifies test-only modules are not compiled into the production build, while confirming the main app entry point is included.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 176001ac-3894-43b6-8cbe-9ee0afc43e86

📥 Commits

Reviewing files that changed from the base of the PR and between 56dda47 and 7c653f9.

📒 Files selected for processing (2)

• src/__tests__/build-excludes-test-code.test.ts
• tsconfig.build.json

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

• tsconfig.build.json

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📝 Walkthrough

Walkthrough

The PR adds tsconfig.build.json with test-source exclusions, updates build scripts to use it, removes an incorrect base-config exclusion, and adds a Vitest check for test-file leakage.

Changes

Build configuration and validation

Layer / File(s)	Summary
Dedicated build configuration and scripts tsconfig.json, tsconfig.build.json, package.json	Build and watch commands now use tsconfig.build.json, which excludes test-only sources and build artifacts.
Test-source exclusion verification src/__tests__/build-excludes-test-code.test.ts	The test lists compiled files, confirms src/index.ts is included, and rejects test-only modules from the build input set.

Estimated code review effort: 2 (Simple) | ~10 minutes

Suggested reviewers: wpak-ai

🚥 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 clearly summarizes the main change: keeping test-only source out of the published build.
Linked Issues check	✅ Passed	The changes address #217 by adding build-specific exclusions and a regression test that prevents test-only files from entering dist.
Out of Scope Changes check	✅ Passed	The diff stays focused on build exclusion fixes and verification, with no obvious unrelated code changes.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
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Additional details and impacted files

@@           Coverage Diff           @@
##             main     #218   +/-   ##
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  Coverage        ?   85.07%           
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  Files           ?       46           
  Lines           ?     2399           
  Branches        ?      826           
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  Hits            ?     2041           
  Misses          ?      357           
  Partials        ?        1           

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