v2.20.2 break ` no-extraneous-dependencies` with webpack alias

OS: Microsoft Windows [Version 10.0.18362.720]
Node: v10.14.2
ESLINT: v5.16.0

In my webpack config, I set a alias name for one of our scoped package for short

alias: {
  'fish': '@sdp.nd/fish'
}

In eslint-plugin-import@2.20.1, it works well while I got no-extraneous-dependencies in eslint-plugin-import@2.20.2.

import { Button } from 'fish'

After debug, I found these code make things different

// src/core/importType.js
// Line 31
// v2.20.2
// subPath = 'node_modules'
// path = 'C:\Users\yj\Desktop\test-collection\demo-base\node_modules\@sdp.nd\fish\es\index.js'
function isSubpath(subpath, path) {
  const normPath = path.replace(/\\/g, '/')
  const normSubpath = subpath.replace(/\\/g, '/').replace(/\/$/, '')
  if (normSubpath.length === 0) {
    return false
  }
  const left = normPath.indexOf(normSubpath)
  const right = left + normSubpath.length
  return left !== -1 &&
        (left === 0 || normSubpath[0] !== '/' && normPath[left - 1] === '/') &&
        (right >= normPath.length || normPath[right] === '/')
}

isSubpath return true in v2.20.2 while return false in v2.20.1.

I found both v2.20.1 and v2.20.2 will report no-extraneous-dependencies on ubuntu and I think v2.20.2 is right, it just fix path error in Window.

I found that

// lib\rules\no-extraneous-dependencies.js
// line 124
const resolved = resolve(name, context) // name == 'fish'
if (!resolved) { return } // resolve = 'C:\Users\yj\Desktop\base-demo-0317\node_modules\@sdp.nd\fish\es\index.js'

const splitName = name.split('/')
const packageName = splitName[0][0] === '@'
    ? splitName.slice(0, 2).join('/')
    : splitName[0]

packageName should be @sdp.nd\fish not fish in this case.

[vvanpo]

I’ve had this plugin pinned at v2.20.0 for a long time due to this bug, but tried upgrading to v2.23.2 and that appears to fix it. @githoniel could you confirm whether this bug is still reproducible with the latest version? Otherwise I think we can close this.

[githoniel]

@IShotTheSheriff 2.20.0 will always skip alias detect in window and will report error on other platform. hope this will be fix soon~~~