[Bug]: @babel/parser doesn't throw a recoverable error for infer that is outside of conditional types

[sosukesuzuki]

💻

• Would you like to work on a fix?

How are you using Babel?

Programmatic API (babel.transform, babel.parse)

Input code

type X = infer U;

Configuration file name

No response

Configuration

const code = "type X = infer U";

require("@babel/parser").parse(code, { plugins: ["typescript"] });

Current and expected behavior

Current:

No error.

Expected:

'infer' declarations are only permitted in the 'extends' clause of a conditional type. error is thrown.

Environment

System:
    OS: macOS 10.15.7
  Binaries:
    Node: 16.13.2 - ~/.nvm/versions/node/v16.13.2/bin/node
    Yarn: 3.1.1 - ~/.nvm/versions/node/v16.13.2/bin/yarn
    npm: 8.1.2 - ~/.nvm/versions/node/v16.13.2/bin/npm
  Monorepos:
    Yarn Workspaces: 3.1.1
  npmPackages:
    @babel/cli: ^7.17.0 => 7.17.0 
    @babel/core: ^7.17.0 => 7.17.8 
    @babel/eslint-config-internal: workspace:^ => 7.16.1 
    @babel/eslint-parser: workspace:^ => 7.17.0 
    @babel/eslint-plugin-development: workspace:^ => 7.17.7 
    @babel/eslint-plugin-development-internal: workspace:^ => 7.17.7 
    @babel/plugin-proposal-dynamic-import: ^7.16.7 => 7.16.7 
    @babel/plugin-proposal-export-namespace-from: ^7.16.7 => 7.16.7 
    @babel/plugin-proposal-object-rest-spread: ^7.16.7 => 7.16.7 
    @babel/plugin-transform-modules-commonjs: ^7.16.8 => 7.16.8 
    @babel/plugin-transform-runtime: ^7.17.0 => 7.17.0 
    @babel/preset-env: ^7.16.11 => 7.16.11 
    @babel/preset-flow: ^7.16.7 => 7.16.7 
    @babel/preset-typescript: ^7.16.7 => 7.16.7 
    @babel/runtime: ^7.17.0 => 7.17.0 
    babel-plugin-transform-charcodes: ^0.2.0 => 0.2.0 
    eslint: ^8.9.0 => 8.9.0 
    jest: ^27.4.0 => 27.4.0

Possible solution

No response

Additional context

#14476 (comment)

[cap-mfm]

+1, same issue here