"ESLint couldn't find the plugin" notice loses a last character

Tell us about your environment

• ESLint Version: 6.8.0
• Node Version: 12.0.0
• npm Version: 6.14.4

What parser (default, Babel-ESLint, etc.) are you using?

Not relevant, but "@typescript-eslint/parser"

Please show your full configuration:

Configuration

module.exports = {
  extends: [
    "plugin:eslint-config-prettier",
  ],
};

What did you do? Please include the actual source code causing the issue, as well as the command that you used to run ESLint.

eslint --print-config ./eslintrc.js

What did you expect to happen?

The module name being reported as not existing should be … eslint-config-prettier, I’m guessing?

What actually happened? Please include the actual, raw output from ESLint.

Oops! Something went wrong! :(

ESLint: 6.8.0.

ESLint couldn't find the plugin "eslint-plugin-eslint-config-prettie".

(The package "eslint-plugin-eslint-config-prettie" was not found when loaded as a Node module from the directory "C:\Code\tslinttest".)

It's likely that the plugin isn't installed correctly. Try reinstalling by running the following:

    npm install eslint-plugin-eslint-config-prettie@latest --save-dev

The plugin "eslint-plugin-eslint-config-prettie" was referenced from the config file in ".eslintrc.js".

If you still can't figure out the problem, please stop by https://gitter.im/eslint/eslint to chat with the team.

This issue split from: https://github.com/typescript-eslint/tslint-to-eslint-config/issues/439.

Are you willing to submit a pull request to fix this bug?

I’d love to! 🤗

[yeonjuan]

Hi @JoshuaKGoldberg 😃 Thanks for the reporting. 😀

It seems a bug to me; I agree that the error message should be improved

The module name being reported as not existing should be … eslint-config-prettier, I’m guessing?

Maybe not, 🤔 because the actual reason is incorrect configuration.

"plugin:eslint-config-prettier",

The “plugin:xxx” means the use of exported configuration from other plugins. so it should be consists of "plugin:" + {package name} + "/" + {configuration name}

• Using the configuration from a plugin

The extends property value can consist of:

• plugin:
• the package name (from which you can omit the prefix, for example, react)
• /
• the configuration name (for example, recommended)

---

https://github.com/eslint/eslint/blob/015edf6467e33c67b904db037a674d71957a6865/lib/cli-engine/config-array-factory.js#L804

the problem is here. there is no ‘/’ character in extendName so lastIndexOf return -1;

[eslint-deprecated[bot]]

Unfortunately, it looks like there wasn’t enough interest from the team or community to implement this change. While we wish we’d be able to accommodate everyone’s requests, we do need to prioritize. We’ve found that issues failing to reach accepted status after 21 days tend to never be accepted, and as such, we close those issues. This doesn’t mean the idea isn’t interesting or useful, just that it’s not something the team can commit to.

Thanks for contributing to ESLint and we appreciate your understanding.