preflight-checks

Preflight Checks

Run the project's code quality tools before committing. Catch errors early instead of letting pre-commit hooks catch them.

Tool Detection

Detect available tools from project config files. Check in this order:

Config File	Tool	Check Command	Fix Command
package.json scripts	npm/yarn/pnpm	Look for lint, typecheck, format, check scripts	Run with --fix where available
.eslintrc* / eslint.config.*	ESLint	npx eslint <files>	npx eslint --fix <files>
tsconfig.json	TypeScript	npx tsc --noEmit	Manual fix required
.prettierrc* / prettier in package.json	Prettier	npx prettier --check <files>	npx prettier --write <files>
pyproject.toml with [tool.ruff]	Ruff	ruff check <files>	ruff check --fix <files> && ruff format <files>
pyproject.toml with [tool.mypy] / mypy.ini	mypy	mypy <files>	Manual fix required
pyproject.toml with [tool.black]	Black	black --check <files>	black <files>
.flake8 / setup.cfg with [flake8]	Flake8	flake8 <files>	Manual fix required
go.mod	Go	go vet ./...	gofmt -w <files>
Cargo.toml	Rust	cargo clippy	cargo clippy --fix
.pre-commit-config.yaml	pre-commit	pre-commit run --files <files>	Runs auto-fix internally

Execution Order

Run tools in this order. Each step can change code that later steps check.

1. Formatters (auto-fix): prettier, black, ruff format, gofmt
2. Linters (auto-fix where possible): eslint --fix, ruff check --fix
3. Type checkers (manual fix): tsc, mypy, pyright

Scope

Only check files that are staged or modified. Don't run checks on the entire codebase.

# Staged files
git diff --cached --name-only --diff-filter=ACM

# Unstaged modified files
git diff --name-only --diff-filter=ACM

Filter to relevant extensions for each tool (e.g., only .ts/.tsx for tsc, only .py for ruff).

Auto-Fix Protocol

1. Run the formatter/linter with its fix flag
2. Re-stage any files that were modified: git add <fixed-files>
3. Report what was changed: "Fixed 3 formatting issues in src/auth/login.ts"

When to Run

• Before git commit (used by /ce:commit)
• Before claiming work is complete
• Before creating a PR (used by /ce:pr)

Failure Handling

Distinguish between fixable and non-fixable errors:

Fixable (auto-fix and move on):

• Formatting errors (whitespace, trailing commas, import ordering)
• Simple lint errors with auto-fix support

Needs human decision (report and stop):

• Type errors (wrong types, missing properties)
• Complex lint errors without auto-fix
• Test failures
• Errors you don't understand

Never silently skip a failing check.