Passwordless

[wti806]

Hey there! So you want to contribute to a Firebase SDK?
Before you file this pull request, please read these guidelines:

Discussion

• Read the contribution guidelines (CONTRIBUTING.md).
• If this has been discussed in an issue, make sure to link to the issue here.
  If not, go file an issue about this before creating a pull request to discuss.

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• Make sure all existing tests in the repository pass after your change.
• If you fixed a bug or added a feature, add a new test to cover your code.

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[bojeil-google]

Just one typing issue. Can you also add the demo app changes to test this?

[bojeil-google]

emailLink is optional here. Change to:
signInWithEmailLink(email: string, emailLink?: string): Promise<any>;

[Splaktar]

This PR should have also updated

firebase-js-sdk/packages/firebase/app/index.d.ts

Lines 204 to 206 in d59b724

	interface AuthCredential {
	providerId: string;
	}

to add the signInMethod: string; field, right?

[bojeil-google]

Yes that is correct. Thanks for reporting this.