Fix: operator-assignment invalid autofix with adjacent tokens

[mdjermanovic]

What is the purpose of this pull request? (put an "X" next to item)

[X] Bug fix

Tell us about your environment

• ESLint Version: 6.5.1
• Node Version: 10.16.0
• npm Version: 6.9.0

What parser (default, Babel-ESLint, etc.) are you using?

default

Please show your full configuration:

Configuration

module.exports = {
  parserOptions: {
    ecmaVersion: 2015,
  }
};

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

Online Demo Link

/* eslint operator-assignment: ["error", "never"]*/

foo+=+bar

What did you expect to happen?

Not a syntax error in autofix.

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

/* eslint operator-assignment: ["error", "never"]*/

foo= foo++bar

What changes did you make? (Give an overview)

Check can the tokens be adjacent.

Is there anything you'd like reviewers to focus on?

[platinumazure]

Looks good, thanks for identifying and fixing this!