apps/me coverage discrepancy: local vs CI branch % (35.41 vs 35.03) causes false-negative CI failures

[taterhead247]

Summary

apps/me branch coverage differs between local and GitHub Actions for the same test target, causing threshold failures in CI.

Observed values:

• Local (pnpm test -F f3-me): branch coverage reports 35.41%.
• CI (test-coverage job on GitHub Actions): branch coverage reports 35.03%.

This discrepancy is enough to fail when the threshold is calibrated from local runs.

Impact

• CI can fail even when local runs pass.
• autoUpdate-driven thresholds recorded locally can become incompatible with CI.
• Developers lose confidence in local reproducibility for coverage gates.

Evidence

From failing Actions logs:

• ERROR: Coverage for branches (35.03%) does not meet global threshold (35.41%)

Local CI-mode repro:

• Running with CI=true locally reproduces the lower CI number (35.03%) and failure against 35.41.

Reproduction

1. Ensure Node version from .nvmrc.
2. Run locally:
   • pnpm test -F f3-me
   • Note branch coverage (commonly 35.41% in non-CI env).
3. Run with CI flag:
   • CI=true pnpm test -F f3-me
   • Branch coverage drops to 35.03% (matches GitHub Actions).
4. Compare against configured threshold in apps/me/vitest.config.ts.

Likely Root Cause

Coverage denominator/branch map differs when CI=true.

apps/me/src/env.ts has CI-sensitive logic:

• skipValidation: !!process.env.CI || ...

This introduces different branch execution/coverage behavior between local default runs and CI runs.

Suggested Resolution

• Calibrate apps/me thresholds using CI-mode runs (CI=true) rather than default local runs.
• Prefer stable thresholds for this package (avoid auto drift), e.g. set autoUpdate: false once CI-aligned values are chosen.
• Optionally document a repo convention: coverage threshold updates must be generated under CI-equivalent env.

Follow-ups (optional)

• Add a small script/target for standardized coverage recalibration under CI=true.
• Add a short testing guide note explaining why CI-mode coverage can differ.