Error: Cannot read config package for shareable config using global eslint

[kevinoid]

Running the following steps, which currently installs ESLint v1.10.3, results in the following error:

$ npm install -g eslint
$ git clone -b v1.1.0 https://github.com/algolia/instantsearch.js.git
$ cd instantsearch.js
$ npm install
$ eslint index.js 
/usr/local/lib/node_modules/eslint/lib/config/config-file.js:332
            throw e;
            ^

Error: Cannot read config package: eslint-config-algolia
Error: Cannot find module 'eslint-config-algolia'
Referenced from: /tmp/instantsearch.js/.eslintrc
    at Function.Module._resolveFilename (module.js:337:15)
    at Function.Module._load (module.js:287:25)
    at Module.require (module.js:366:17)
    at require (module.js:385:17)
    at loadPackage (/usr/local/lib/node_modules/eslint/lib/config/config-file.js:168:16)
    at loadConfigFile (/usr/local/lib/node_modules/eslint/lib/config/config-file.js:212:18)
    at load (/usr/local/lib/node_modules/eslint/lib/config/config-file.js:385:18)
    at /usr/local/lib/node_modules/eslint/lib/config/config-file.js:326:36
    at Array.reduceRight (native)
    at applyExtends (/usr/local/lib/node_modules/eslint/lib/config/config-file.js:309:28)

If the last command is replaced with ./node_modules/.bin/eslint index.js the command completes without error. The error appears to result from "extends": "algolia" being translated to require("eslint-config-algolia") which fails when run from a global eslint installation because eslint-config-algolia is not installed globally.

This has a few obvious workarounds:

1. eslint-config-algolia can be installed globally. The downside is that now developers must determine which eslint modules a project requires, then install them globally before linting. It's workable, but painful for developers, and especially painful to new project contributors who are more likely to either forgo linting or contributing.
2. The extends declaration can be made relative in .eslintrc (e.g. by changing "extends": "algolia" to "extends": "./node_modules/eslint-config-algolia/index.js" or similar - and recursively for transitive dependencies). This appears to be a common idiom but it is both verbose and requires all transitive dependencies to use this strategy (which may be out of a project's control, and is not currently ubiquitous).
3. eslint can always be invoked through the project-local installation in node_modules. This is both workable and has the added benefit of allowing projects to require a specific version of eslint. But it requires all programs which invoke eslint to comply, which is reasonably difficult to enforce on an ongoing basis. Nearly all programs I checked currently assume eslint is installed in $PATH, which does the right thing when invoked via npm run but the wrong thing when launched by a user (e.g. via editor tools).

There are likely other workarounds that I haven't considered. Even if such workarounds are generally straightforward, the current situation leaves some developers with an error message that they have to investigate and fix. It would be great if this pain could be avoided by a change to ESLint. For example, would it be possible to resolve referenced modules (config, plugin, etc.) relative to the current package and fallback to global resolution only if local resolution fails?

Thanks for considering,
Kevin

Note: There is some overlap with #3458, and a solution to either issue might affect the other.

[eslintbot]

@kevinoid Thanks for the issue! If you're reporting a bug, please be sure to include:

1. The version of ESLint you are using (run eslint -v)
2. What you did (the source code and ESLint configuration)
3. The actual ESLint output complete with numbers
4. What you expected to happen instead

Requesting a new rule? Please see Proposing a New Rule for instructions.

[mysticatea]

Thank you for this issue.

Related issues: #4529, #3293, #1238

eslint-cli might help you.

[nzakas]

This is a known limitation. If you are using a globally installed ESLint, your shareable config must also be globally installed.

[kevinoid]

Thanks @mysticatea, that is very helpful indeed.

@nzakas, if this is a known issue, is it documented anywhere? Perhaps I overlooked it. It seems to be affecting a lot of people and certainly took a while for me to figure out. Would you consider adding an explanation to the error message which is printed when require fails so users are at least pointed in the right direction?