--fix leaves trailing spaces

[rchl]

Tell us about your environment

• ESLint Version: 5.6.0
• eslint-plugin-vue Version: 4.0.0
• Node Version: 8.11.3

Please show your full configuration:

.eslintrc.yaml

---
env:
    node: true
parserOptions:
    parser: 'babel-eslint'
    ecmaVersion: 2018
    sourceType: module
plugins:
    - vue
extends:
    - 'eslint:recommended'
    - 'plugin:vue/recommended'
rules:
    indent:
        - error
        - 4
    linebreak-style: error
    no-var: error
    prefer-const: error
    quotes:
        - error
        - single
    semi: error
    no-console:
        - error
        - allow: [warn, error, info]
    vue/html-indent:
        - error
        - 4

What did you do? Please include the actual source code causing the issue.

Triggered formatting of code using eslint --fix

<template>
    <div a b>Foo</div>
</template>

What did you expect to happen?

Template to be formatted without leaving trailing spaces.

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

Formatted code includes spaces (denoted by <space>) in places where line-break was added.

<template>
    <div<space>
        a<space>
        b>Foo</div>
</template>

[michalsnik]

Hey @rchl Thanks for posting this issue.

Can you confirm whether you have the same issue with eslint-plugin-vue@next?

[rchl]

1. eslint-plugin-vue@next doesn't fix the problem. In fact it makes things worse because formatting ends up like this:

<template>
    <div 
a="1" 
b="2"
>Foo</div>
</template>

Tried on 5.0.0-beta.3.

2. I have found a workaround for this. I've added no-trailing-spaces: error rule. I imagine this gets rid of the problem because with this rule eslint is applying fix for trailing spaces so it cleans up after the plugin.

[ota-meshi]

I've added no-trailing-spaces: error rule.

You need to add no-trailing-spaces rule as you say.

If you do not add it, the same issue may remain with eslint other rules.
For example, trailing spaces remain in autofix of array-bracket-newline.

[rchl]

It fixes the problem but it's a workaround. Ideally none of the rules would introduce trailing spaces.

[mysticatea]

Thank you for this issue.

However, this is a philosophy of ESLint. Each rule is standalone and does one thing well. This means a rule which handles line breaks doesn't handle other than line breaks. You need a combination of some rules to get the result you want.