typescript is a dependency but only included as a devDependency #770
Description
This issue is with regards to the package @typescript-eslint/typescript-estree.
The compiled version of parser.js contains this line:
const ts = __importStar(require("typescript")); // leave this as * as ts so people using util package don't need syntheticDefaultImportsIf TypeScript isn't present, the package cannot be used.
In my case, I have an eslint plugin that use this package under the hood. The plugin fails to load if TypeScript isn't present (i.e. the plugin is being used to lint a project that doesn't use TypeScript).
$ /path/to/project/node_modules/.bin/eslint .
Error: Failed to load plugin 'someplugin' declared in '.eslintrc': Cannot find module 'typescript'
Require stack:
- /path/to/project/node_modules/@typescript-eslint/typescript-estree/dist/parser.js
- /path/to/project/node_modules/eslint-plugin-someplugin/lib/index.js
- /path/to/project/node_modules/eslint/lib/cli-engine/config-array-factory.js
- /path/to/project/node_modules/eslint/lib/cli-engine/cascading-config-array-factory.js
- /path/to/project/node_modules/eslint/lib/cli-engine/cli-engine.js
- /path/to/project/node_modules/eslint/lib/cli-engine/index.js
- /path/to/project/node_modules/eslint/lib/cli.js
- /path/to/project/node_modules/eslint/bin/eslint.js
Referenced from: /path/to/project/.eslintrc
at Function.Module._resolveFilename (internal/modules/cjs/loader.js:623:15)
at Function.Module._load (internal/modules/cjs/loader.js:527:27)
at Module.require (internal/modules/cjs/loader.js:681:19)
at require (/path/to/project/node_modules/v8-compile-cache/v8-compile-cache.js:161:20)
at Object.<anonymous> (/path/to/project/node_modules/@typescript-eslint/typescript-estree/dist/parser.js:17:25)
at Module._compile (/path/to/project/node_modules/v8-compile-cache/v8-compile-cache.js:192:30)
at Object.Module._extensions..js (internal/modules/cjs/loader.js:785:10)
at Module.load (internal/modules/cjs/loader.js:641:32)
at Function.Module._load (internal/modules/cjs/loader.js:556:12)
at Module.require (internal/modules/cjs/loader.js:681:19)
error Command failed with exit code 2.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.I believe the solution to this issue would be to have @typescript-eslint/typescript-estree declare TypeScript as either a dependency or a peerDependency.