'loc' of null error when using babel-eslint as a custom parser

[Robula]

• Node Version: 8.9.1
• eslint Version: 4.10.0
• vue-eslint-parser Version: 2.0.1-beta.2
• babel-eslint Version: 8.0.2

This is directly related to the issue I created here vuejs/eslint-plugin-vue#189.

I have discovered that the above issue is not resident in eslint-plugin-vue and that the issue likely lies with the interactions between babel-eslint and vue-eslint-parser.

As described in vuejs/eslint-plugin-vue#189 the combination of vue-eslint-parser and babel-eslint produces a error when running the linter.

Example

[mysticatea]

Thank you for the report.

Hmmm, but I still cannot reproduce it. I'm seeing no errors.

[Robula]

@mysticatea Could you try changing @Component() to

@Component({
    mounted: {}
})

and rerun the linter please?

[mysticatea]

Sure, but I got the same result.

Could you run npm ls and share the result?

[mysticatea]

This is mine

[email protected] C:\Users\t-nagashima.MSS\dev\sandbox
+-- [email protected]
| +-- @babel/[email protected]
| | +-- [email protected] deduped
| | +-- [email protected] deduped
| | `-- [email protected]
| +-- @babel/[email protected]
| | +-- @babel/[email protected] deduped
| | +-- @babel/[email protected]
| | | +-- @babel/[email protected]
| | | | `-- @babel/[email protected] deduped
| | | +-- @babel/[email protected]
| | | | +-- @babel/[email protected] deduped
| | | | +-- @babel/[email protected] deduped
| | | | +-- [email protected] deduped
| | | | `-- [email protected] deduped
| | | +-- @babel/[email protected] deduped
| | | `-- @babel/[email protected] deduped
| | +-- @babel/[email protected] deduped
| | +-- [email protected] deduped
| | +-- [email protected] deduped
| | +-- [email protected]
| | +-- [email protected]
| | | `-- [email protected]
| | |   `-- [email protected] deduped
| | `-- [email protected] deduped
| +-- @babel/[email protected]
| | +-- [email protected] deduped
| | +-- [email protected] deduped
| | `-- [email protected]
| `-- [email protected]
+-- [email protected]
| +-- [email protected]
| | +-- [email protected]
| | +-- [email protected]
| | +-- [email protected]
| | `-- [email protected]
| +-- [email protected]
| | +-- [email protected]
| | | +-- [email protected]
| | | +-- [email protected] deduped
| | | +-- [email protected]
| | | | `-- [email protected] deduped
| | | +-- [email protected]
| | | | `-- [email protected]
| | | `-- [email protected]
| | +-- [email protected] deduped
| | `-- [email protected] deduped
| +-- [email protected]
| | +-- [email protected]
| | | `-- [email protected]
| | |   `-- [email protected]
| | +-- [email protected]
| | `-- [email protected]
| |   `-- [email protected]
| +-- [email protected]
| | +-- [email protected]
| | +-- [email protected]
| | | +-- [email protected]
| | | +-- [email protected] deduped
| | | +-- [email protected] deduped
| | | +-- [email protected]
| | | +-- [email protected]
| | | +-- [email protected]
| | | | `-- [email protected] deduped
| | | `-- [email protected]
| | `-- [email protected]
| +-- [email protected]
| | +-- [email protected]
| | | +-- [email protected]
| | | `-- [email protected]
| | +-- [email protected]
| | | `-- [email protected]
| | `-- [email protected]
| |   `-- [email protected]
| +-- [email protected]
| | `-- [email protected]
| +-- [email protected]
| | +-- [email protected] deduped
| | `-- [email protected]
| +-- [email protected]
| | +-- [email protected]
| | | +-- [email protected] deduped
| | | `-- [email protected] deduped
| | `-- [email protected] deduped
| +-- [email protected]
| | +-- [email protected]
| | `-- [email protected]
| |   `-- [email protected]
| +-- [email protected]
| | `-- [email protected] deduped
| +-- [email protected]
| +-- [email protected]
| +-- [email protected]
| | +-- [email protected]
| | | +-- [email protected]
| | | +-- [email protected]
| | | | +-- [email protected]
| | | | | +-- [email protected]
| | | | | | `-- [email protected]
| | | | | +-- [email protected]
| | | | | +-- [email protected] deduped
| | | | | +-- [email protected] deduped
| | | | | +-- [email protected] deduped
| | | | | `-- [email protected] deduped
| | | | +-- [email protected]
| | | | +-- [email protected]
| | | | | `-- [email protected]
| | | | |   `-- [email protected] deduped
| | | | +-- [email protected] deduped
| | | | +-- [email protected]
| | | | +-- [email protected]
| | | | | `-- [email protected]
| | | | `-- [email protected]
| | | |   `-- [email protected] deduped
| | | +-- [email protected]
| | | `-- [email protected]
| | |   `-- [email protected] deduped
| | `-- [email protected]
| +-- [email protected]
| +-- [email protected]
| | +-- [email protected]
| | +-- [email protected]
| | | +-- [email protected] deduped
| | | `-- [email protected]
| | +-- [email protected] deduped
| | +-- [email protected] deduped
| | +-- [email protected]
| | | `-- [email protected] deduped
| | `-- [email protected]
| +-- [email protected]
| +-- [email protected]
| +-- [email protected]
| +-- [email protected]
| | +-- [email protected]
| | +-- [email protected] deduped
| | +-- [email protected]
| | | `-- [email protected]
| | |   +-- [email protected]
| | |   | `-- [email protected]
| | |   `-- [email protected]
| | +-- [email protected]
| | +-- [email protected]
| | | +-- [email protected]
| | | +-- [email protected]
| | | `-- [email protected]
| | |   `-- [email protected]
| | +-- [email protected]
| | | `-- [email protected] deduped
| | +-- [email protected] deduped
| | +-- [email protected]
| | +-- [email protected]
| | | `-- [email protected]
| | +-- [email protected]
| | +-- [email protected]
| | | `-- [email protected] deduped
| | +-- [email protected]
| | | +-- [email protected]
| | | `-- [email protected] deduped
| | +-- [email protected] deduped
| | `-- [email protected]
| +-- [email protected]
| | `-- [email protected]
| +-- [email protected]
| | +-- [email protected]
| | | `-- [email protected]
| | `-- [email protected]
| +-- [email protected]
| +-- [email protected]
| | +-- [email protected]
| | `-- [email protected]
| |   `-- [email protected] deduped
| +-- [email protected]
| +-- [email protected]
| | `-- [email protected]
| |   +-- [email protected]
| |   `-- [email protected]
| +-- [email protected]
| | `-- [email protected]
| +-- [email protected]
| +-- [email protected]
| | +-- [email protected]
| | +-- [email protected]
| | +-- [email protected] deduped
| | +-- [email protected] deduped
| | +-- [email protected] deduped
| | `-- [email protected]
| +-- [email protected]
| +-- [email protected]
| +-- [email protected]
| +-- [email protected]
| | +-- [email protected]
| | | `-- [email protected]
| | `-- [email protected]
| +-- [email protected]
| +-- [email protected]
| | `-- [email protected]
| +-- [email protected]
| +-- [email protected]
| | +-- [email protected] deduped
| | +-- [email protected]
| | +-- [email protected] deduped
| | +-- [email protected] deduped
| | +-- [email protected]
| | | `-- [email protected] deduped
| | `-- [email protected] deduped
| `-- [email protected]
`-- [email protected]
  +-- [email protected] deduped
  +-- [email protected] deduped
  +-- [email protected] deduped
  +-- [email protected] deduped
  `-- [email protected] deduped

[Robula]

Sure, here you go

Robs-MBP:vep-issue robfinbow$ npm ls
/Users/robfinbow/DEV/vep-issue
├─┬ [email protected]
│ ├─┬ @babel/[email protected]
│ │ ├── [email protected] deduped
│ │ ├── [email protected] deduped
│ │ └── [email protected]
│ ├─┬ @babel/[email protected]
│ │ ├── @babel/[email protected] deduped
│ │ ├─┬ @babel/[email protected]
│ │ │ ├─┬ @babel/[email protected]
│ │ │ │ └── @babel/[email protected] deduped
│ │ │ ├─┬ @babel/[email protected]
│ │ │ │ ├── @babel/[email protected] deduped
│ │ │ │ ├── @babel/[email protected] deduped
│ │ │ │ ├── [email protected] deduped
│ │ │ │ └── [email protected] deduped
│ │ │ ├── @babel/[email protected] deduped
│ │ │ └── @babel/[email protected] deduped
│ │ ├── @babel/[email protected] deduped
│ │ ├── [email protected] deduped
│ │ ├── [email protected] deduped
│ │ ├── [email protected]
│ │ ├─┬ [email protected]
│ │ │ └─┬ [email protected]
│ │ │   └── [email protected] deduped
│ │ └── [email protected] deduped
│ ├─┬ @babel/[email protected]
│ │ ├── [email protected] deduped
│ │ ├── [email protected] deduped
│ │ └── [email protected]
│ └── [email protected]
├─┬ [email protected]
│ ├─┬ [email protected]
│ │ ├── [email protected]
│ │ ├── [email protected]
│ │ ├── [email protected]
│ │ └── [email protected]
│ ├─┬ [email protected]
│ │ ├─┬ [email protected]
│ │ │ ├── [email protected]
│ │ │ ├── [email protected] deduped
│ │ │ ├─┬ [email protected]
│ │ │ │ └── [email protected] deduped
│ │ │ ├─┬ [email protected]
│ │ │ │ └── [email protected]
│ │ │ └── [email protected]
│ │ ├── [email protected] deduped
│ │ └── [email protected] deduped
│ ├─┬ [email protected]
│ │ ├─┬ [email protected]
│ │ │ └─┬ [email protected]
│ │ │   └── [email protected]
│ │ ├── [email protected]
│ │ └─┬ [email protected]
│ │   └── [email protected]
│ ├─┬ [email protected]
│ │ ├── [email protected]
│ │ ├─┬ [email protected]
│ │ │ ├── [email protected]
│ │ │ ├── [email protected] deduped
│ │ │ ├── [email protected] deduped
│ │ │ ├── [email protected]
│ │ │ ├── [email protected]
│ │ │ ├─┬ [email protected]
│ │ │ │ └── [email protected] deduped
│ │ │ └── [email protected]
│ │ └── [email protected]
│ ├─┬ [email protected]
│ │ ├─┬ [email protected]
│ │ │ ├── [email protected]
│ │ │ └── [email protected]
│ │ ├─┬ [email protected]
│ │ │ └── [email protected]
│ │ └─┬ [email protected]
│ │   └── [email protected]
│ ├─┬ [email protected]
│ │ └── [email protected]
│ ├─┬ [email protected]
│ │ ├── [email protected] deduped
│ │ └── [email protected]
│ ├─┬ [email protected]
│ │ ├─┬ [email protected]
│ │ │ ├── [email protected] deduped
│ │ │ └── [email protected] deduped
│ │ └── [email protected] deduped
│ ├─┬ [email protected]
│ │ ├── [email protected]
│ │ └─┬ [email protected]
│ │   └── [email protected]
│ ├─┬ [email protected]
│ │ └── [email protected] deduped
│ ├── [email protected]
│ ├── [email protected]
│ ├─┬ [email protected]
│ │ ├─┬ [email protected]
│ │ │ ├── [email protected]
│ │ │ ├─┬ [email protected]
│ │ │ │ ├─┬ [email protected]
│ │ │ │ │ ├─┬ [email protected]
│ │ │ │ │ │ └── [email protected]
│ │ │ │ │ ├── [email protected]
│ │ │ │ │ ├── [email protected] deduped
│ │ │ │ │ ├── [email protected] deduped
│ │ │ │ │ ├── [email protected] deduped
│ │ │ │ │ └── [email protected] deduped
│ │ │ │ ├── [email protected]
│ │ │ │ ├─┬ [email protected]
│ │ │ │ │ └─┬ [email protected]
│ │ │ │ │   └── [email protected] deduped
│ │ │ │ ├── [email protected] deduped
│ │ │ │ ├── [email protected]
│ │ │ │ ├─┬ [email protected]
│ │ │ │ │ └── [email protected]
│ │ │ │ └─┬ [email protected]
│ │ │ │   └── [email protected] deduped
│ │ │ ├── [email protected]
│ │ │ └─┬ [email protected]
│ │ │   └── [email protected] deduped
│ │ └── [email protected]
│ ├── [email protected]
│ ├─┬ [email protected]
│ │ ├── [email protected]
│ │ ├─┬ [email protected]
│ │ │ ├── [email protected] deduped
│ │ │ └── [email protected]
│ │ ├── [email protected] deduped
│ │ ├── [email protected] deduped
│ │ ├─┬ [email protected]
│ │ │ └── [email protected] deduped
│ │ └── [email protected]
│ ├── [email protected]
│ ├── [email protected]
│ ├── [email protected]
│ ├─┬ [email protected]
│ │ ├── [email protected]
│ │ ├── [email protected] deduped
│ │ ├─┬ [email protected]
│ │ │ └─┬ [email protected]
│ │ │   ├─┬ [email protected]
│ │ │   │ └── [email protected]
│ │ │   └── [email protected]
│ │ ├── [email protected]
│ │ ├─┬ [email protected]
│ │ │ ├── [email protected]
│ │ │ ├── [email protected]
│ │ │ └─┬ [email protected]
│ │ │   └── [email protected]
│ │ ├─┬ [email protected]
│ │ │ └── [email protected] deduped
│ │ ├── [email protected] deduped
│ │ ├── [email protected]
│ │ ├─┬ [email protected]
│ │ │ └── [email protected]
│ │ ├── [email protected]
│ │ ├─┬ [email protected]
│ │ │ └── [email protected] deduped
│ │ ├─┬ [email protected]
│ │ │ ├── [email protected]
│ │ │ └── [email protected] deduped
│ │ ├── [email protected] deduped
│ │ └── [email protected]
│ ├─┬ [email protected]
│ │ └── [email protected]
│ ├─┬ [email protected]
│ │ ├─┬ [email protected]
│ │ │ └── [email protected]
│ │ └── [email protected]
│ ├─┬ [email protected]
│ │ └── [email protected]
│ ├─┬ [email protected]
│ │ ├── [email protected]
│ │ └─┬ [email protected]
│ │   └── [email protected] deduped
│ ├── [email protected]
│ ├─┬ [email protected]
│ │ └─┬ [email protected]
│ │   ├── [email protected]
│ │   └── [email protected]
│ ├─┬ [email protected]
│ │ └── [email protected]
│ ├── [email protected]
│ ├─┬ [email protected]
│ │ ├── [email protected]
│ │ ├── [email protected]
│ │ ├── [email protected] deduped
│ │ ├── [email protected] deduped
│ │ ├── [email protected] deduped
│ │ └── [email protected]
│ ├── [email protected]
│ ├── [email protected]
│ ├── [email protected]
│ ├─┬ [email protected]
│ │ ├─┬ [email protected]
│ │ │ └── [email protected]
│ │ └── [email protected]
│ ├── [email protected]
│ ├─┬ [email protected]
│ │ └── [email protected]
│ ├── [email protected]
│ ├─┬ [email protected]
│ │ ├── [email protected] deduped
│ │ ├── [email protected]
│ │ ├── [email protected] deduped
│ │ ├── [email protected] deduped
│ │ ├─┬ [email protected]
│ │ │ └── [email protected] deduped
│ │ └── [email protected] deduped
│ └── [email protected]
├── [email protected]
├── [email protected]
└─┬ [email protected]
  ├── [email protected] deduped
  ├── [email protected] deduped
  ├── [email protected] deduped
  ├── [email protected] deduped
  └── [email protected] deduped

I can't see much difference except that you have eslint-plugin-react (what treachery! 😄)

[mysticatea]

Thank you.

But sorry, I didn't find meaningful different.... (I checked estraverse, babel-eslint, eslint-scope. The babel-eslint is finding eslint-scope and estraverse in order to monkey-patching. If there is different dedupe situation, I guessed it's the cause. But no...)

I realized your screenshot has yarn.lock, so I tried to use yarn, but I got the same result (no errors)...

[mysticatea]

Maybe I got it.

[cmizzi]

I've got the same bug here (my configuration seems to be the same as @Robula)

[mysticatea]

Yes. This happens when a code is using stage 0-3 syntaxes or type annotations. I'm working on this, but I need more time.

The cause is that vue-eslint-parser does not get the monkey patching of babel-eslint. The monkey patching affects to ESLint core, but does not to this parser. I'm working to remove the monkey patching on the new feature of ESLint core.

[Robula]

Thank you for the explanation and your efforts to resolve this @mysticatea.

[mysticatea]

Thank you for your patience.

I'm still working in progress, but I have gotten that eslint/eslint#8755 is accepted at the last ESLint TSC Meeting and can advance babel/babel-eslint#542 to remove the monkey patching.

[mysticatea]

[email protected] has been released. It includes the enhancement and I removed the monkeypatch from babel-eslint. I'll advance to fix this issue.