ln-741-linter-configurator
Type: L3 Worker Category: 7XX Project Bootstrap Parent: ln-740-quality-setup
Configures code linting and formatting tools for TypeScript, .NET, and Python projects.
Purpose & Scope
Does:
Detects which linter stack to configure based on project type Checks for existing linter configurations Generates appropriate config files from templates Installs required dependencies Verifies linter runs without errors
Does NOT:
Configure pre-commit hooks (ln-742 does this) Set up test infrastructure (ln-743 does this) Modify source code Supported Stacks Technology Linter Formatter Config Files TypeScript/React ESLint 9+ (flat config) Prettier eslint.config.mjs, .prettierrc .NET Roslyn Analyzers dotnet format .editorconfig, Directory.Build.props Python Ruff Ruff (built-in) ruff.toml or pyproject.toml Phase 1: Check Existing Configuration
Before generating configs, check what already exists.
Files to Check:
Stack Config Files Glob Pattern TypeScript ESLint config eslint.config., .eslintrc TypeScript Prettier config .prettierrc, prettier.config. .NET Editor config .editorconfig .NET Build props Directory.Build.props Python Ruff config ruff.toml, pyproject.toml
Decision Logic:
If config exists and is complete: SKIP (inform user) If config exists but incomplete: ASK user to merge or replace If no config exists: CREATE from template Phase 2: Generate Configuration
Use templates from references/ folder. Customize placeholders based on project.
TypeScript/React:
Copy eslint_template.mjs to project root as eslint.config.mjs Copy prettier_template.json as .prettierrc Add scripts to package.json: "lint": "eslint ." "lint:fix": "eslint . --fix" "format": "prettier --write ." "format:check": "prettier --check ."
.NET:
Copy editorconfig_template.ini as .editorconfig Copy directory_build_props_template.xml as Directory.Build.props Ensure analyzers package reference included
Python:
Copy ruff_template.toml as ruff.toml OR merge into existing pyproject.toml under [tool.ruff] Add scripts to pyproject.toml or document commands Phase 3: Install Dependencies
Install required packages for each stack.
TypeScript/React:
npm install -D eslint @eslint/js typescript-eslint eslint-plugin-react eslint-plugin-react-hooks eslint-config-prettier prettier
CRITICAL: eslint-config-prettier is REQUIRED to prevent ESLint/Prettier conflicts.
.NET:
Analyzers configured via Directory.Build.props No separate install needed
Python:
pip install ruff
OR with uv:
uv add --dev ruff
Phase 4: Verify Setup
After configuration, verify linter works.
TypeScript:
npm run lint npm run format:check
Expected: Exit code 0
.NET:
dotnet format --verify-no-changes
Expected: Exit code 0
Python:
ruff check . ruff format --check .
Expected: Exit code 0
On Failure: Check error output, adjust config, re-verify.
Critical Rules
RULE 1: Always include eslint-config-prettier when using ESLint + Prettier together.
RULE 2: Use ESLint flat config format (eslint.config.mjs), NOT legacy .eslintrc.
RULE 3: Ruff replaces Black, isort, flake8, and many other Python tools. Do NOT install them separately.
RULE 4: Never disable strict TypeScript rules without documented reason.
Definition of Done Appropriate config files created for detected stack Dependencies installed Lint command runs without errors on project source Format command runs without errors No ESLint/Prettier conflicts (eslint-config-prettier installed) User informed of available lint/format commands Reference Files File Purpose eslint_template.mjs ESLint flat config template prettier_template.json Prettier config template editorconfig_template.ini .NET editorconfig template directory_build_props_template.xml .NET analyzers template ruff_template.toml Python Ruff config template linter_guide.md Detailed configuration guide Error Handling Error Cause Resolution ESLint/Prettier conflict Missing eslint-config-prettier Install and add to config TypeScript parse errors Parser version mismatch Align typescript-eslint with TS version Ruff not found Not installed pip install ruff or uv add ruff dotnet format fails Missing SDK Install .NET SDK
Version: 2.0.0 Last Updated: 2026-01-10