What is @typescript-eslint/typescript-estree?
The @typescript-eslint/typescript-estree package is a parser that converts TypeScript source code into an ESTree-compatible form. It is primarily used in the context of ESLint to enable linting of TypeScript code by converting TypeScript syntax into a format that ESLint can understand and work with.
What are @typescript-eslint/typescript-estree's main functionalities?
Parsing TypeScript code to ESTree
This feature allows you to parse TypeScript code and get an Abstract Syntax Tree (AST) that is compatible with ESTree. This is useful for tools that need to analyze or manipulate the syntax of TypeScript code.
const tsEStree = require('@typescript-eslint/typescript-estree');
const code = 'let x: number = 1;';
const ast = tsEStree.parse(code, { jsx: false });
console.log(ast);
Parsing TypeScript code with JSX
This feature is similar to the previous one but includes support for JSX syntax, which is commonly used in React applications. It allows the parser to correctly interpret JSX elements within TypeScript code.
const tsEStree = require('@typescript-eslint/typescript-estree');
const code = '<div>Hello, TypeScript!</div>';
const ast = tsEStree.parse(code, { jsx: true });
console.log(ast);
Parsing a file
This feature allows you to parse the contents of a TypeScript file by reading the file and then parsing the code. It is useful when you want to analyze or lint a file directly.
const tsEStree = require('@typescript-eslint/typescript-estree');
const fs = require('fs');
const filePath = './example.ts';
const code = fs.readFileSync(filePath, 'utf8');
const ast = tsEStree.parse(code, { filePath });
console.log(ast);
Other packages similar to @typescript-eslint/typescript-estree
typescript-eslint-parser
This package was the predecessor to @typescript-eslint/typescript-estree and has been deprecated in favor of the newer package. It provided similar functionality in terms of parsing TypeScript code for ESLint.
babel-eslint
babel-eslint is a parser that allows ESLint to run on source code that is transpiled with Babel. While it is not TypeScript-specific, it can be used with Babel's TypeScript preset to parse TypeScript code.
espree
Espree is the default parser for ESLint and is built on top of Acorn. It is designed to parse ECMAScript (JavaScript) code. While it does not natively support TypeScript, it serves a similar purpose for JavaScript code as @typescript-eslint/typescript-estree does for TypeScript.