midnight-cq:quality-check

Run and Interpret Quality Checks

This skill is for running checks and fixing failures. To set up quality tooling from scratch, use midnight-cq:quality-init.

Command Quick Reference

Check	Command	Scope
Lint + format (changed)	biome ci --changed	Files changed vs default branch
Lint + format (all)	biome ci	Entire project
Lint + format (fix)	biome check --write	Auto-fix
Type check	tsc --noEmit	All TS files
Contract compile	compact-compiler --skip-zk	All .compact files
Unit/contract tests	vitest run	All test suites
E2E tests	npx playwright test	DApp browser tests
Full pre-push suite	biome ci && tsc --noEmit && vitest run	Everything

Run commands from the project root. If biome is not on the path, prefix with npx.

How to Read Results

Biome

Each violation uses this format:

path/to/file.ts:line:col rule/name LEVEL description

Example:

src/index.ts:12:5 style/useConst ERROR This variable is never reassigned.

• rule/name — maps directly to a rule at biomejs.dev/linter/rules/<rule-name>. Open the URL for the rationale and suggested fix.
• LEVEL is always ERROR in Midnight projects (no warnings in CI — see biome.json).
• Format violations say format as the rule and show a unified diff of what Biome expects. Apply with biome check --write.
• Exit code 1 means at least one violation. Exit code 0 means clean.

tsc --noEmit

Each error uses this format:

path/to/file.ts(line,col): error TS#### description

In Midnight projects, tsc errors frequently originate from:

1. Stale Compact compiler output — types in managed/ are regenerated by compact-compiler. If .compact source changed but managed/ was not recompiled, tsc will report phantom type errors. Fix: run compact-compiler --skip-zk first, then re-run tsc --noEmit.
2. Missing or wrong imports from managed/ — the compiler emits named exports; check the generated .d.ts for the exact export name.
3. Strict null / undefined — common when accessing ledger state that may not be initialised yet. Narrow with an explicit guard.

vitest

A failing test shows:

FAIL src/test/MyContract.test.ts
  ● transferOwnership › should fail when called by unauthorized

    Error: Ownable: caller is not the owner

      at ProxyHandler.<anonymous> (node_modules/@openzeppelin-compact/contracts-simulator/dist/...)
      at ...
      at MyContractSimulator.transferOwnership (src/test/simulators/MyContractSimulator.ts:42:5)
      at Object.<anonymous> (src/test/MyContract.test.ts:67:7)

Reading the trace:

• Error message — maps directly to a assert string in the .compact source. Search the contract for the literal message to find the failing assertion.
• Simulator file + line — shows which user-friendly method triggered the circuit.
• Test file + line — the exact expect(...) or method call that failed.
• Ignore the deep ProxyHandler frames in node_modules — they are internal simulator machinery and carry no debugging signal.
• A test that expected a throw but didn't get one reports Received function did not throw. Check whether the circuit path that should reject was actually reached.

Common Quick Fixes

Symptom	Fix
Biome format violations across many files	npx biome check --write — rewrites all auto-fixable issues in one pass
tsc errors about types in managed/	npx compact-compiler --skip-zk && npx tsc --noEmit — recompile contracts first
vitest test throws unexpected error string	Search the .compact source for the error message; the assertion path diverged — update the test or the contract
biome ci --changed passes locally but CI fails	CI runs biome ci (all files); run npx biome ci locally to reproduce
Playwright tests time out on wallet/transaction steps	Increase timeout in playwright.config.ts for blockchain-heavy operations; default 30 s is too short for proof generation

Not For

• Setting up quality tooling from scratch → use midnight-cq:quality-init
• Writing new Compact contract tests → use midnight-cq:compact-testing
• Writing new DApp E2E tests → use midnight-cq:dapp-testing

Reference Files

Topic	Reference
Each Biome rule explained with fix guidance	references/biome-diagnostics.md
Common simulator errors and how to fix them	references/test-failures.md
CI-specific debugging guide	references/ci-troubleshooting.md