@kilcekru/ts-basics

Provides basic configuration for typescript and eslint.

• Setup
• tsconfig
• eslint

Setup

npm i -D @kilcekru/ts-basics

ts-basics has a peer dependency on typescript >= 4.3
npm i -D typescript@latest

tsconfig

There are four flavours available:

• tsconfig-node-app: for node >=16; use this for nodejs apps
• tsconfig-node-library: for node >=16; use this for libraries (enables declaration files)
• tsconfig-react-app: for browser; use this for react apps (es2021 is used, support for older browsers not given)
• tsconfig-react-library: for browser, use this for libraries (enables declaration files)

To use one of those flavours, just extend your tsconfig from it:
This will give you the basic configuration, but does not specify any paths.
You still have to add include, outDir,...

Example:

{
    "extends": "@kilcekru/ts-basics/tsconfig-node-app.json",
    "compilerOptions": {
        "outDir": "dist",
    },
    "include": [
        "src/**/*"
    ]
}

eslint

The base config for eslint is available at .eslintrc.js.
To use it just extend your eslintrc from this file.

Example:

module.exports = {
    env: {
        node: true,
        browser: true,
        es2020: true,
    },
    parserOptions: {
        tsconfigRootDir: __dirname,
        project: ["./tsconfig.json"],
    },
    extends: [require.resolve("@kilcekru/ts-basics/.eslintrc.js")],
};

Don't forget to add a file called .eslintignore in your project root.
Specify all files that don't need linting (like node_modules and build artifacts)

Eslint and typescript
@typescript-eslint/parser is used for all typescript files.
For this to work it is necessary that all typescript file are included in a tsconfig.json file
and this tsconfig files need to be set in parserOptions.project. Eslint will throw an error, if a file is not referenced correctly.

If you have typescript files, that are not part of your build (config, tests),
you can create a tsconfig.eslint.json which just includes those files (don't forget to add this file to parserOptions.project in the .eslintrc.js).

{
    "extends": "@kilcekru/ts-basics/tsconfig-node-app.json",
    "include": ["config/**/*", "tests/**/*"]
}

Performance
Eslint gets exponential slower on bigger projects.
If you use it in a monorepo, create a separate .eslintrc.js for each package.
Linting each package will be faster and use less memory than linting everything at once.