If a function does not return anything, it makes no sense to use its output. Specifically, passing it to another function, or assigning its "result" to a variable is probably a bug because such functions return undefined, which is probably not what was intended.

Note that this rule requires Node.js to be available during analysis.

Noncompliant Code Example

function foo() {
  console.log("Hello, World!");
}

a = foo();

Compliant Solution

function foo() {
  console.log("Hello, World!");
}

foo();