TypeScript Type Predicate Generator Helpers

Common Commands

Build: cd generator && npm run build
Check: cd generator && npm run check (typecheck + tests)
Run tests: cd generator && npm test
Run single test: cd generator && npx vitest [pattern]
E2E test: cd tests/e2e && ./test.sh
Generate type guards: npm run --silent build && node dist/index.js [file.ts]

Code Style

Use TypeScript strict mode
Naming: PascalCase for types, camelCase for variables/functions/methods
Prefer explicit types over inferred types in signatures
Use satisfies operator for type safety validation
Follow factory pattern for AST node creation
Use constants for reusable strings/values

Code Structure

Split model from code generation logic
Create intermediate type representation
Each type gets dedicated class with proper inheritance
Group related functionality in well-named classes
Optimize for speed and readability

Error Handling

Use specific error types defined in errors.ts
Focus on early validation to prevent runtime errors
Use assertion functions from helpers.ts