Update the linkWithCredential API to call the signUp endpoint

.changeset/tiny-items-grin.md

@@ -0,0 +1,5 @@
+---
+'@firebase/auth': patch
+---
+
+Fixes https://github.com/firebase/firebase-js-sdk/issues/7675

packages/auth/src/api/account_management/email_and_password.test.ts

@@ -27,6 +27,7 @@ import * as mockFetch from '../../../test/helpers/mock_fetch';
 import { ServerError } from '../errors';
 import {
   applyActionCode,
+  linkEmailPassword,
   resetPassword,
   updateEmailPassword
 } from './email_and_password';
@@ -91,6 +92,65 @@ describe('api/account_management/resetPassword', () => {
   });
 });
 
+describe('api/account_management/linkEmailPassword', () => {
+  const request = {
+    idToken: 'id-token',
+    returnSecureToken: true,
+    email: '[email protected]',
+    password: 'new-password'
+  };
+
+  let auth: TestAuth;
+
+  beforeEach(async () => {
+    auth = await testAuth();
+    mockFetch.setUp();
+  });
+
+  afterEach(mockFetch.tearDown);
+
+  it('should POST to the correct endpoint', async () => {
+    const mock = mockEndpoint(Endpoint.SIGN_UP, {
+      idToken: 'id-token'
+    });
+
+    const response = await linkEmailPassword(auth, request);
+    expect(response.idToken).to.eq('id-token');
+    expect(mock.calls[0].request).to.eql(request);
+    expect(mock.calls[0].method).to.eq('POST');
+    expect(mock.calls[0].headers!.get(HttpHeader.CONTENT_TYPE)).to.eq(
+      'application/json'
+    );
+    expect(mock.calls[0].headers!.get(HttpHeader.X_CLIENT_VERSION)).to.eq(
+      'testSDK/0.0.0'
+    );
+  });
+
+  it('should handle errors', async () => {
+    const mock = mockEndpoint(
+      Endpoint.SIGN_UP,
+      {
+        error: {
+          code: 400,
+          message: ServerError.INVALID_EMAIL,
+          errors: [
+            {
+              message: ServerError.INVALID_EMAIL
+            }
+          ]
+        }
+      },
+      400
+    );
+
+    await expect(linkEmailPassword(auth, request)).to.be.rejectedWith(
+      FirebaseError,
+      'Firebase: The email address is badly formatted. (auth/invalid-email).'
+    );
+    expect(mock.calls[0].request).to.eql(request);
+  });
+});
+
 describe('api/account_management/updateEmailPassword', () => {
   const request = {
     idToken: 'id-token',

packages/auth/src/api/account_management/email_and_password.ts

@@ -25,6 +25,7 @@ import {
 } from '../index';
 import { IdTokenResponse } from '../../model/id_token';
 import { MfaEnrollment } from './mfa';
+import { SignUpRequest, SignUpResponse } from '../authentication/sign_up';
 
 export interface ResetPasswordRequest {
   oobCode: string;
@@ -69,6 +70,20 @@ export async function updateEmailPassword(
   >(auth, HttpMethod.POST, Endpoint.SET_ACCOUNT_INFO, request);
 }
 
+// Used for linking an email/password account to an existing idToken. Uses the same request/response
+// format as updateEmailPassword.
+export async function linkEmailPassword(
+  auth: Auth,
+  request: SignUpRequest
+): Promise<SignUpResponse> {
+  return _performApiRequest<SignUpRequest, SignUpResponse>(
+    auth,
+    HttpMethod.POST,
+    Endpoint.SIGN_UP,
+    request
+  );
+}
+
 export interface ApplyActionCodeRequest {
   oobCode: string;
   tenantId?: string;

packages/auth/src/api/authentication/sign_up.ts

@@ -27,6 +27,7 @@ import { IdTokenResponse } from '../../model/id_token';
 import { Auth } from '../../model/public_types';
 
 export interface SignUpRequest {
+  idToken?: string;
   returnSecureToken?: boolean;
   email?: string;
   password?: string;