chore(auth): Completed unit tests for AuthenticatorViewModel's signIn region (#194)

Co-authored-by: Edison Zhang <edisonzz@amazon.com>

Author: edisooon

authenticator/src/test/java/com/amplifyframework/ui/authenticator/AuthenticatorViewModelTest.kt

@@ -220,6 +220,73 @@ class AuthenticatorViewModelTest {
         viewModel.currentStep shouldBe AuthenticatorStep.SignInConfirmTotpCode
     }
 
+    @Test
+    fun `SMS MFA Code next step shows the SignInConfirmMfa screen`() = runTest {
+        coEvery { authProvider.fetchAuthSession() } returns Success(mockAuthSession(isSignedIn = false))
+        coEvery { authProvider.signIn(any(), any()) } returns Success(
+            mockSignInResult(signInStep = AuthSignInStep.CONFIRM_SIGN_IN_WITH_SMS_MFA_CODE)
+        )
+
+        viewModel.start(mockAuthenticatorConfiguration(initialStep = AuthenticatorStep.SignIn))
+
+        viewModel.signIn("username", "password")
+        viewModel.currentStep shouldBe AuthenticatorStep.SignInConfirmMfa
+    }
+
+    @Test
+    fun `Custom Challenge next step shows the SignInConfirmCustomAuth screen`() = runTest {
+        coEvery { authProvider.fetchAuthSession() } returns Success(mockAuthSession(isSignedIn = false))
+        coEvery { authProvider.signIn(any(), any()) } returns Success(
+            mockSignInResult(signInStep = AuthSignInStep.CONFIRM_SIGN_IN_WITH_CUSTOM_CHALLENGE)
+        )
+
+        viewModel.start(mockAuthenticatorConfiguration(initialStep = AuthenticatorStep.SignIn))
+
+        viewModel.signIn("username", "password")
+        viewModel.currentStep shouldBe AuthenticatorStep.SignInConfirmCustomAuth
+    }
+
+    @Test
+    fun `New Password next step shows the SignInConfirmNewPassword screen`() = runTest {
+        coEvery { authProvider.fetchAuthSession() } returns Success(mockAuthSession(isSignedIn = false))
+        coEvery { authProvider.signIn(any(), any()) } returns Success(
+            mockSignInResult(signInStep = AuthSignInStep.CONFIRM_SIGN_IN_WITH_NEW_PASSWORD)
+        )
+
+        viewModel.start(mockAuthenticatorConfiguration(initialStep = AuthenticatorStep.SignIn))
+
+        viewModel.signIn("username", "password")
+        viewModel.currentStep shouldBe AuthenticatorStep.SignInConfirmNewPassword
+    }
+
+    @Test
+    fun `Confirm SignUp next step, get error from resendSignUpCode, stays in SignIn screen`() = runTest {
+        coEvery { authProvider.fetchAuthSession() } returns Success(mockAuthSession(isSignedIn = false))
+        coEvery { authProvider.signIn(any(), any()) } returns Success(
+            mockSignInResult(signInStep = AuthSignInStep.CONFIRM_SIGN_UP)
+        )
+        coEvery { authProvider.resendSignUpCode(any()) } returns AmplifyResult.Error(mockAuthException())
+
+        viewModel.start(mockAuthenticatorConfiguration(initialStep = AuthenticatorStep.SignIn))
+
+        viewModel.signIn("username", "password")
+        viewModel.currentStep shouldBe AuthenticatorStep.SignIn
+    }
+
+    @Test
+    fun `Confirm SignUp next step shows the SignUpConfirm screen`() = runTest {
+        coEvery { authProvider.fetchAuthSession() } returns Success(mockAuthSession(isSignedIn = false))
+        coEvery { authProvider.signIn(any(), any()) } returns Success(
+            mockSignInResult(signInStep = AuthSignInStep.CONFIRM_SIGN_UP)
+        )
+        coEvery { authProvider.resendSignUpCode(any()) } returns Success(mockk())
+
+        viewModel.start(mockAuthenticatorConfiguration(initialStep = AuthenticatorStep.SignIn))
+
+        viewModel.signIn("username", "password")
+        viewModel.currentStep shouldBe AuthenticatorStep.SignUpConfirm
+    }
+
     @Test
     fun `MFA selection next step shows error if allowedMFATypes is null`() = runTest {
         coEvery { authProvider.fetchAuthSession() } returns Success(mockAuthSession(isSignedIn = false))