[question] Enforce internal/parent import order with alias

[andreafspeziale]

Hello!
I can't find a way to enforce import order to internal / parent using aliases. Maybe it is just not possible.

Example:

--- src
     |--- folderA
           |--- fileA1.ts
           |--- fileA2.ts
     |--- folderB
           |--- folderC
                 |--- fileC1.ts
           |--- fileB1.ts
           |--- fileB2.ts

Set an alias in my tsconfig.json

{
  "compilerOptions": {
    ...
    "baseUrl": "./",
    "paths": {
      "@src/*": ["src/*"],
    }
  }
}

In fileC1.ts

import { foo } from '@src/folderA/fileA1'
import { bar } from '@src/folderB/fileB1'

I would really love to be able to enforce the import from B (parent) to happen after import A (internal) but I'm not sure it is possible since I believe that alias would "hide" it.

Thanks in advance!

[ljharb]

I'm unclear on what you're asking. Wouldn't folderA and folderB both be internal?

[andreafspeziale]

Maybe I'm just totally wrong but based on my understanding being in fileC1.ts, file fileB1 is a parent and fileA1.ts is internal. So given a configuration like

'import/order': [
      2,
      {
        groups: ['builtin', 'external', 'internal', 'parent', 'sibling', 'index'],
        'newlines-between': 'never'
      },
    ],

I would like to enforce

import { bar } from '@src/folderB/fileB1' after import { foo } from '@src/folderA/fileA1'

With the above given config and (I believe) since I'm using alias the linter doesn't care about the order so:

import { bar } from '@src/folderB/fileB1'
import { foo } from '@src/folderA/fileA1'

is still valid.

[ljharb]

oh right, you're in fileC at that point. Yes, folderB would be a parent and folderA would be internal.

So what you're saying is, you WANT them to be sorted so that folderA comes first (because it's internal), but because it's using a TS alias, it's recognizing it as a parent?

Can you share your eslint config? Hopefully you're using the TS eslint resolver.

[andreafspeziale]

You got it! (btw I don't really know if it's folderA recognize as parent or is it viceversa - so it's folderB recognize as internal, what I know is that switching their order would not trigger any error)

eslintrc.js

module.exports = {
  parser: '@typescript-eslint/parser',
  parserOptions: {
    project: 'tsconfig.json',
    sourceType: 'module',
    tsconfigRootDir: __dirname,
  },
  plugins: ['@typescript-eslint/eslint-plugin', 'unused-imports'],
  extends: [
    'plugin:@typescript-eslint/recommended',
    'plugin:import/recommended',
    'plugin:import/typescript',
    'plugin:prettier/recommended',
    "plugin:@dword-design/import-alias/recommended",
  ],
  root: true,
  env: {
    node: true,
    jest: true,
  },
  ignorePatterns: ['.eslintrc.js'],
  rules: {
    '@typescript-eslint/explicit-function-return-type': 1,
    '@typescript-eslint/explicit-module-boundary-types': 0,
    '@typescript-eslint/no-explicit-any': 0,
    '@typescript-eslint/no-inferrable-types': 0,
    '@typescript-eslint/no-shadow': 1,
    '@typescript-eslint/no-unused-vars': [1, { ignoreRestSiblings: true }],
    'import/namespace': 0,
    'import/no-extraneous-dependencies': [2, { devDependencies: ['**/test/**'] }],
    'import/order': [
      2,
      {
        groups: ['builtin', 'external', 'internal', 'parent', 'sibling', 'index'],
        'newlines-between': 'never'
      },
    ],
    'lines-between-class-members': [2, 'always', { exceptAfterSingleLine: true }],
    'unused-imports/no-unused-imports': 2,
  },
  overrides: [
    {
      files: ['*.decorator.ts'],
      rules: {
        '@typescript-eslint/explicit-function-return-type': 0,
      },
    },
  ],
  settings: {
    'import/parsers': {
      '@typescript-eslint/parser': ['.ts', '.tsx'],
    },
    'import/resolver': {
      typescript: {
        alwaysTryTypes: true,
      },
    },
  },
};

[ljharb]

cc @JounQin if the TS resolver is reporting @src/folderB/fileB1 as a parent instead of internal, there's not much the plugin can do, I think.

[JounQin]

cc @JounQin if the TS resolver is reporting @src/folderB/fileB1 as a parent instead of internal, there's not much the plugin can do, I think.

@ljharb Sorry I didn't notice the mention previously, but I'm not quite sure to understand why it's related to the TS resolver, does it resolve a incorrect absolute path?

[ljharb]

I'm not certain, but it seems like it's resolving it as a relative path (a parent) rather than a bare specifier (in node_modules).

[JounQin]

@ljharb

I'm not certain, but it seems like it's resolving it as a relative path (a parent) rather than a bare specifier (in node_modules).

I'm still confused, it's using TS alias, and @src is not a bare specifier (in node_modules).

Besides, @andreafspeziale can you please provide a minimal reproduction?

[ljharb]

Right, but a TS alias should still report as if it's npm linked in, i assume?

[JounQin]

@andreafspeziale Can you try DEBUG=eslint-import-resolver-typescript first to see what absolute paths are resolved?

Right, but a TS alias should still report as if it's npm linked in, i assume?

@ljharb I don't think that's possible, ts resolver returns absolute paths, it's not npm linked, is it?

[andreafspeziale]

@JounQin Sure I'll try to ship a sample ASAP

[andreafspeziale]

@JounQin @ljharb As promised.
https://github.com/andreafspeziale/eslint-issue-sample

So we can also be sure that the issue is not me messing-up something or just not understanding that it's simply not possible since aliases are "flattening" everything ^^