The linkWithCredential function is sending the request to the wrong endpoint.

[minjunkyeong]

Operating System

macOS 14.1.1

Browser Version

Chrome/120.0.6099.234

Firebase SDK Version

10.7.1

Firebase SDK Product:

Auth

Describe your project's tooling

Traditional Web Development Tools(html, javascript), vite

Describe the problem

During the process of linking accounts, I encountered an issue where, after successfully signing up with the Google account abc@gmail.com, attempting to link this Google account with an existing email/password account (also abc@gmail.com) leads to unexpected behavior. Instead of linking the two accounts, the sdk appears to be treating the operation as a new account creation. The linkWithCredential function, which is expected to send a request to the 'setAccountInfo' endpoint for linking accounts, seems to be sending the request to the 'signupNewUser' endpoint instead.

Steps and code to reproduce issue

Scenario

1. Sign up through Google using the account abc@gmail.com.
2. Attempt to sign up again using the same email abc@gmail.com, but this time with the email/password authentication method.
3. Since the account has already been used for registration, attempt to link the accounts.
4. Use linkWithCredential function to link email and password credentials to a user account.

But Internally in the sdk, the linkWithCredential function is sending a link request to the wrong endpoint.

Code snippet

const googleProvider = new GoogleAuthProvider({});

const credential = await signInWithPopup(auth, googleProvider);

const emailCredential = EmailAuthProvider.credential(
    'abc@gmail.com',
    '123qwe!!',
);

const result = await linkWithCredential(credential.user, emailCredential);

Running the linkWithCredential function sends a request to the "https://identitytoolkit.googleapis.com/v1/accounts:signUp?key=[API_KEY]" endpoint, which is used to create accounts. (not expected)

It sholud sends a request to "https://identitytoolkit.googleapis.com/v1/accounts:update?key=[API_KEY]" (expected)
[rest api doc]

This problem occurs in firebase sdk v10.7.1

I found that sdk v10.0.0 doesn't have this problem.

[pragatimodi]

Hi, thanks for reporting this issue.
This seems to be the expected behavior. Please let us know in case there is an issue with the functionality here.