Merge pull request #148 from playwright-community/fix-await

fix: Fewer false negatives for `no-useless-await`

Author: mskelton

src/rules/no-useless-await.ts

@@ -1,29 +1,33 @@
 import { Rule } from 'eslint';
-import { getStringValue } from '../utils/ast';
+import * as ESTree from 'estree';
+import { getStringValue, isPageMethod } from '../utils/ast';
 
-const methods = new Set([
+const locatorMethods = new Set([
   'and',
-  'childFrames',
   'first',
-  'frame',
-  'frameLocator',
-  'frames',
   'getByAltText',
   'getByLabel',
   'getByPlaceholder',
   'getByRole',
   'getByTestId',
   'getByText',
   'getByTitle',
-  'isClosed',
-  'isDetached',
   'last',
   'locator',
+  'nth',
+  'or',
+]);
+
+const pageMethods = new Set([
+  'childFrames',
+  'frame',
+  'frameLocator',
+  'frames',
+  'isClosed',
+  'isDetached',
   'mainFrame',
   'name',
-  'nth',
   'on',
-  'or',
   'page',
   'parentFrame',
   'setDefaultNavigationTimeout',
@@ -34,6 +38,16 @@ const methods = new Set([
   'workers',
 ]);
 
+function isSupportedMethod(node: ESTree.CallExpression) {
+  if (node.callee.type !== 'MemberExpression') return false;
+
+  const name = getStringValue(node.callee.property);
+  return (
+    locatorMethods.has(name) ||
+    (pageMethods.has(name) && isPageMethod(node, name))
+  );
+}
+
 export default {
   create(context) {
     return {
@@ -46,8 +60,7 @@ export default {
         if (callee.type !== 'MemberExpression') return;
 
         // Must be a method we care about
-        const { property } = callee;
-        if (!methods.has(getStringValue(property))) return;
+        if (!isSupportedMethod(node.argument)) return;
 
         const start = node.loc!.start;
         const range = node.range!;

test/spec/no-useless-await.spec.ts

@@ -187,6 +187,7 @@ runRuleTester('no-useless-await', rule, {
     'await foo(".my-element")',
     'await foo.bar()',
     'await foo.bar(".my-element")',
+    'await foo.isClosed(".my-selector")',
 
     'page.getByRole(".my-element")',
     'page.locator(".my-element")',