Use Promise.withResolvers to simplify promise handling (#11666)

* Use Promise.withResolvers to simplify promise handling changelog: Internal, Code Quality, Simplify code using newly-available JavaScript features * Pass dummy error object to rejected promise
18F · Dec 18, 2024 · 5e546a4 · 5e546a4
1 parent 870e1d8
commit 5e546a4
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Showing 2 changed files with 6 additions and 33 deletions.
diff --git a/app/javascript/packages/analytics/digital-analytics-program.spec.ts b/app/javascript/packages/analytics/digital-analytics-program.spec.ts
@@ -4,12 +4,7 @@ import { pathToFileURL } from 'node:url';
 
 describe('digital analytics program', () => {
   it('parses without syntax error', async () => {
-    // Future: Replace with Promise.withResolvers once supported
-    // See: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise/withResolvers
-    let resolve;
-    const promise = new Promise((_resolve) => {
-      resolve = _resolve;
-    });
+    const { promise, resolve } = Promise.withResolvers<void>();
 
     // Reference: https://github.com/nodejs/node/issues/30682
     const toDataURL = (source: string) =>

diff --git a/spec/javascript/packages/document-capture/hooks/use-async-spec.jsx b/spec/javascript/packages/document-capture/hooks/use-async-spec.jsx
@@ -23,19 +23,8 @@ describe('document-capture/hooks/use-async', () => {
   }
 
   it('returns suspense resource that renders fallback', async () => {
-    let resolve;
-    const createPromise = sinon
-      .stub()
-      .onCall(0)
-      .returns(
-        new Promise((_resolve) => {
-          resolve = () => {
-            _resolve();
-          };
-        }),
-      )
-      .onCall(1)
-      .throws();
+    const { promise, resolve } = Promise.withResolvers();
+    const createPromise = sinon.stub().onCall(0).returns(promise).onCall(1).throws();
 
     const { container, findByText } = render(<Parent createPromise={createPromise} />);
 
@@ -47,25 +36,14 @@ describe('document-capture/hooks/use-async', () => {
   });
 
   it('returns suspense resource that renders error fallback', async () => {
-    let reject;
-    const createPromise = sinon
-      .stub()
-      .onCall(0)
-      .returns(
-        new Promise((_resolve, _reject) => {
-          reject = () => {
-            _reject(new Error());
-          };
-        }),
-      )
-      .onCall(1)
-      .throws();
+    const { promise, reject } = Promise.withResolvers();
+    const createPromise = sinon.stub().onCall(0).returns(promise).onCall(1).throws();
 
     const { container, findByText } = render(<Parent createPromise={createPromise} />);
 
     expect(container.textContent).to.equal('Loading');
 
-    reject();
+    reject(new Error());
 
     expect(await findByText('Error')).to.be.ok();
     expect(console).to.have.loggedError();