当在eslint中启用space-before-blocks时，仅强制执行一个空间而不是几个空间

Question

How can properly configure a rule to enforce that before a code block with braces it only contains one single space instead several spaces or tabs?

So far I have been using:

/* globals isCorrect, aValue callback */
/*eslint space-before-blocks: "error"*/

if (isCorrect)  { // That should be incorrect, more than one space
    callback('correct');
} else if(aValue == 5) { // That should be correct, only one space
    callback('aValue');
} else      { // That is also incorrect, tabs!
    callback('incorrect');
}

Answer 1

You can use no-multi-spaces for that! Add /* no-multi-spaces: "error" */ to your example and try it in the demo :

/* globals isCorrect, aValue callback */
/* eslint space-before-blocks: "error" */
/* eslint no-multi-spaces: "error" */

if (isCorrect)  { // That should be incorrect, more than one space
    callback('correct');
} else if(aValue == 5) { // That should be correct, only one space
    callback('aValue');
} else      { // That is also incorrect, tabs!
    callback('incorrect');
}

That should give you the errors you want:

5:17 - Multiple spaces found before '{'. (no-multi-spaces)
9:13 - Multiple spaces found before '{'. (no-multi-spaces)