fix(eslint-plugin): require-named-effect does not allow to use void operator (#135)

fix: require-named-effect does not allow to use void operator

Author: AntoineThibi

example-app/eslint-breaking-examples/break-require-named-effect.tsx

@@ -7,12 +7,18 @@ import { useEffect } from "react";
 
 const MyComponent = () => {
   const doAThing = (t: number) => t;
+  const doNothing = () => {};
+  const initializeStuff = () => Promise.resolve();
 
   useEffect(() => {
     const abc = 1;
     doAThing(abc);
   }, []);
 
+  // Does not trigger an error:
+  useEffect(() => doNothing(), []);
+  useEffect(() => void initializeStuff(), []);
+
   return <></>;
 };
 

packages/eslint-plugin/docs/rules/require-named-effect.md

@@ -33,6 +33,10 @@ useEffect(theNameOfAFunction(), []);
 useEffect(() => theNameOfAFunction(), []);
 ```
 
+```jsx
+useEffect(() => void theNameOfAFunction(), []);
+```
+
 ```jsx
 useEffect(() => {
   theOnlyChildIsAFunctionCall();

packages/eslint-plugin/lib/rules/require-named-effect.ts

@@ -52,6 +52,14 @@ export const requireNamedEffectRule: Rule.RuleModule = {
         return true;
       }
 
+      // It's a unary expression that contains a function call:
+      //   `useEffect(() => void theNameOfAFunction(), []);`
+      if (body.type === "UnaryExpression") {
+        if (body.argument.type === "CallExpression") {
+          return true;
+        }
+      }
+
       // There's a function body, but it just calls another function:
       //   `useEffect(() => {
       //     theOnlyChildIsAFunctionCall();