test(mock-api): fix error.stack and add currentTestName to error (#38769)

After tests moved to co-location, the `error.stack` logic would fail to
produce any meaningful information for jest to report when an error is
encountered.

In addition to this, the thrown error would not fail the correct test.
To mitigate confusion we'll assert `afterEach` test to ensure there was
no mock `Client` error.

static/app/__mocks__/api.tsx

@@ -56,6 +56,18 @@ function compareRecord(want: Record<string, any>, check: Record<string, any>): b
   return true;
 }
 
+afterEach(() => {
+  // if any errors are caught we console.warn them
+  const errors = Object.values(Client.errors);
+  if (errors.length > 0) {
+    for (const err of errors) {
+      // eslint-disable-next-line no-console
+      console.warn(err);
+    }
+    Client.errors = {};
+  }
+});
+
 class Client implements ApiNamespace.Client {
   static mockResponses: MockResponse[] = [];
 
@@ -202,31 +214,29 @@ class Client implements ApiNamespace.Client {
 
   // XXX(ts): We type the return type for requestPromise and request as `any`. Typically these woul
 
+  static errors: Record<string, Error> = {};
   request(url: string, options: Readonly<ApiNamespace.RequestOptions> = {}): any {
     const [response, mock] = Client.findMockResponse(url, options) || [
       undefined,
       undefined,
     ];
-
     if (!response || !mock) {
+      const methodAndUrl = `${options.method || 'GET'} ${url}`;
       // Endpoints need to be mocked
-      const err = new Error(
-        `No mocked response found for request: ${options.method || 'GET'} ${url}`
-      );
+      const err = new Error(`No mocked response found for request: ${methodAndUrl}`);
 
       // Mutate stack to drop frames since test file so that we know where in the test
       // this needs to be mocked
       const lines = err.stack?.split('\n');
-      const startIndex = lines?.findIndex(line => line.includes('tests/js/spec'));
+      const startIndex = lines?.findIndex(line => line.includes('.spec.'));
       err.stack = ['\n', lines?.[0], ...(lines?.slice(startIndex) ?? [])].join('\n');
 
       // Throwing an error here does not do what we want it to do....
       // Because we are mocking an API client, we generally catch errors to show
       // user-friendly error messages, this means in tests this error gets gobbled
-      // up and developer frustration ensues. Use `setTimeout` to get around this
-      setTimeout(() => {
-        throw err;
-      });
+      // up and developer frustration ensues.
+      // We track the errors on a static member and warn afterEach test.
+      Client.errors[methodAndUrl] = err;
     } else {
       // has mocked response
 

tests/js/throw-on-react-error.js

@@ -32,7 +32,7 @@ jest.spyOn(console, 'error').mockImplementation((message, ...args) => {
     originalConsoleError(message, ...args);
     const err = new Error('Warnings received from console.error()');
     const lines = err.stack?.split('\n');
-    const startIndex = lines?.findIndex(line => line.includes('tests/js/spec'));
+    const startIndex = lines?.findIndex(line => line.includes('.spec.'));
     err.stack = ['\n', lines?.[0], ...lines?.slice(startIndex)].join('\n');
 
     throw err;