eslint-config-standard-with-typescript/readme.md

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An [ESLint shareable config](https://eslint.org/docs/developer-guide/shareable-configs) for TypeScript that is based on [eslint-config-standard](https://github.com/standard/eslint-config-standard) and has TypeScript specific rules from [@typescript-eslint/eslint-plugin](https://www.npmjs.com/package/@typescript-eslint/eslint-plugin).

# Peer dependencies 

This package specifies the following `peerDependencies`:

- TypeScript, which you may already have installed
- [ESLint](https://github.com/eslint/eslint)
- 3 Peer dependencies of [eslint-config-standard](https://github.com/standard/eslint-config-standard)
- [@typescript-eslint/eslint-plugin](https://www.npmjs.com/package/@typescript-eslint/eslint-plugin); ESLint rules for TypeScript.

Yes, this is a large number of `peerDependencies`.
This is due to [a known limitation in ESLint](https://github.com/eslint/eslint/issues/3458).

# @typescript-eslint dependencies

This package has `@typescript-eslint/parser` in `dependencies`.  
And it has `@typescript-eslint/eslint-plugin` in `peerDependencies`.  
Both are specified as ranges.
It's probably safest for the installed versions of these packages to be the same.
This can be achieved by:

1. Pin (exact version) the `@typescript-eslint/eslint-plugin` in `package.json`.
1. Have a `package-lock.json` which locks the version of the `@typescript-eslint/parser` sub-dependency.

And both pin/lock to the same version.

# Yarn

Yarn does not automatically install `peerDependencies`,
so if that's what you're using, install them manually.
Here is an example, but use it only for reference,
because your decisions regarding version ranges and range specifiers may vary.

```
yarn add --dev \
  typescript@\* \
  eslint@^8.0.1 \
  eslint-plugin-promise@^6.0.0 \
  eslint-plugin-import@^2.25.2 \
  eslint-plugin-n@^15.0.0 \
  @typescript-eslint/eslint-plugin@^6.4.0 \
  eslint-config-standard-with-typescript@latest
```

# Example config

Here is an example `.eslintrc.js`.
Pay close attention to the `files` property, because it [determines which files are linted][specifying-target-files-to-lint].

```js
module.exports = {
  overrides: [
    {
      files: ['*.js', '*.jsx', '*.ts', '*.tsx'],
      extends: 'standard-with-typescript'
    }
  ],
}
```

Note: the config exported by this package sets `parserOptions.project = true`.
Read about the `project` option [here](https://github.com/typescript-eslint/typescript-eslint/blob/master/packages/parser/README.md#configuration).

There are [some more `parserOptions`](https://github.com/typescript-eslint/typescript-eslint/blob/master/packages/parser/README.md#configuration) you may care about.

[specifying-target-files-to-lint]: https://eslint.org/docs/latest/use/configure/configuration-files#specifying-target-files-to-lint

# Example command line usage:

```
$ npx eslint .
```