eslint-plugin-no-type-assertion

eslint-plugin-no-type-assertion

Disallow type assertions in TypeScript code. The rule will forbid both as operator, as well as angle-bracketed syntax, unlessused for const assertions.

The following code becomes invalid:

const foo: unknown = 42;

const bar = <number>foo;
const baz = foo as number;

Installation

Ensure you have ESLint and @typescript-eslint/parser installed:

$ yarn add eslint @typescript-eslint/parser -D

Next, install this plugin:

$ yarn add eslint-plugin-no-type-assertion -D

Configuration

In your ESLint configuratio, ensure you're using @typescript-eslint/parser as a parser and it's set up correctly:

{
  "parser": "@typescript-eslint/parser",
  "parserOptions": {
    "ecmaVersion": 2018
  }
}

Add eslint-plugin-no-type-assertion to the plugin list:

{
  "plugins": ["no-type-assertion"]
}

Enable the rule:

{
  "rules": {
    "no-type-assertion/no-type-assertion": "error"
  }
}

Changelog

1.1.0

• Add support for angle-bracketed assertion syntax

1.0.1

• Fix rule name

1.0.0

• Initial version