Google TypeScript Style

To use gts as a hook in the pre-commit framework, add the following to your .pre-commit-config.yaml file. Ensure you specify a valid rev (tag or SHA).

repos:
  - repo: https://github.com/google/gts
    rev: '' # Use the sha / tag you want to point at
    hooks:
      - id: gts

To set up Google TypeScript Style in your project, run the init command. This will:

• Add an opinionated tsconfig.json file.
• Add necessary devDependencies to your package.json.
• Add the following scripts to your package.json:
  • lint: Lints and checks for formatting problems.
  • fix: Automatically fixes formatting and linting problems.
  • clean: Removes output files.
  • compile: Compiles source code using the TypeScript compiler.
  • pretest, posttest, and prepare: Convenience integrations.
• Add a default template project if no source folder is present.

npx gts init

You can use gts as a shared configuration for ESLint. Create an eslint.config.js file in your project directory and extend the shared config using require('gts').

module.exports = [
  ...require('gts'),
];

The gts package exports a pre-configured ESLint configuration using defineConfig. It provides a comprehensive set of rules for JavaScript and TypeScript, including integration with Prettier, eslint-plugin-n, and typescript-eslint.

When you require gts in your eslint.config.js, it applies:

• ESLint recommended rules.
• Prettier configuration to avoid conflicts.
• Strict rules for variable scoping (no-var, prefer-const), equality (eqeqeq), and formatting.
• Restrictions on using .only in describe or it blocks.
• TypeScript-specific rules for .ts and .tsx files, including parser settings for tsconfig.json and recommended @typescript-eslint rules.

To use gts with ESLint, use the defineConfig utility from eslint/config to merge the gts configuration with your project's specific ignores. The gts configuration is imported from ./src/index.js and is spread into the configuration array.

'use strict';
const config = require('./src/index.js');
const ignores = require('./eslint.ignores.js');
const defineConfig = require('eslint/config').defineConfig;

module.exports = defineConfig([{ignores}, ...config]);

The gts lint command can be scoped to specific files or patterns rather than the entire project directory.

gts lint index.ts
gts lint one.ts two.ts three.ts
gts lint *.ts

The clean function removes files generated by the build process. It identifies the directory to delete by reading the compilerOptions.outDir setting from the tsconfig.json file located in the project's target root directory.

Requirements:

• The tsconfig.json must have compilerOptions.outDir explicitly defined.
• The outDir value cannot be . (the current directory), as this would attempt to delete all source files.

If outDir is not defined or is set to ., the function will log an error and return false. Otherwise, it recursively removes the directory and returns true.

The installDefaultTemplate function populates a src/ directory with a default project structure.

Constraint: The template is only installed if the target src/ directory does not already contain any .ts files. If .ts files are detected, the installation is skipped to prevent overwriting existing work.

When running gts commands, you can use the following options to modify behavior:

--help
-y, --yes
-n, --no
--dry-run
--yarn

When using addScripts, gts ensures your package.json contains the following standard scripts:

The <pkg-manager> is determined by your configuration (e.g., yarn if enabled).