Rule proposal: JavaScript Expression spacing

[neciu]

This rule should force adding/removing of spaces in JavaScript Expressions.

Given the value of the rule is always:

1. Is wrong

...
  return (
    <div>
      {children}
    </div>
  );
...

2. Is ok

...
  return (
    <div>
      { children }
    </div>
  );
...

Given the value of the rule is never:

1. Is ok

...
  return (
    <div>
      {children}
    </div>
  );
...

2. Is wrong

...
  return (
    <div>
      { children }
    </div>
  );
...

[ljharb]

This is a duplicate of #857 (comment)

[fatfisz]

This is fixed in #1177.