yield-star-spacing 
Rule Details 
This rule enforces spacing around the * in yield* expressions.
Options 
The rule takes one option, an object, which has two keys before and after having boolean values true or false.
- beforeenforces spacing between the- yieldand the- *. If- true, a space is required, otherwise spaces are disallowed.
- afterenforces spacing between the- *and the argument. If it is- true, a space is required, otherwise spaces are disallowed.
The default is {"before": false, "after": true}.
"yield-star-spacing": ["error", {"before": true, "after": false}]The option also has a string shorthand:
- {"before": false, "after": true}→- "after"
- {"before": true, "after": false}→- "before"
- {"before": true, "after": true}→- "both"
- {"before": false, "after": false}→- "neither"
"yield-star-spacing": ["error", "after"]Examples 
after 
Examples of correct code for this rule with the default "after" option:
/*eslint @stylistic/js/yield-star-spacing: ["error", "after"]*/
/*eslint-env es6*/
function* generator() {
  yield* other();
}before 
Examples of correct code for this rule with the "before" option:
/*eslint @stylistic/js/yield-star-spacing: ["error", "before"]*/
/*eslint-env es6*/
function *generator() {
  yield *other();
}both 
Examples of correct code for this rule with the "both" option:
/*eslint @stylistic/js/yield-star-spacing: ["error", "both"]*/
/*eslint-env es6*/
function * generator() {
  yield * other();
}neither 
Examples of correct code for this rule with the "neither" option:
/*eslint @stylistic/js/yield-star-spacing: ["error", "neither"]*/
/*eslint-env es6*/
function*generator() {
  yield*other();
}When Not To Use It 
If your project will not be using generators or you are not concerned with spacing consistency, you do not need this rule.