Route post-merge NewRegistration to the registration form instead of register/wallet

lib/screens/kyc/steps/email/cubits/email_verification/kyc_email_verification_cubit.dart

@@ -3,6 +3,7 @@ import 'dart:developer' as developer;
 import 'package:equatable/equatable.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:realunit_wallet/packages/service/dfx/dfx_auth_service.dart';
+import 'package:realunit_wallet/packages/service/dfx/models/wallet/real_unit_registration_state.dart';
 import 'package:realunit_wallet/packages/service/dfx/real_unit_registration_service.dart';
 import 'package:realunit_wallet/packages/utils/jwt_decoder.dart';
 
@@ -70,23 +71,32 @@ class KycEmailVerificationCubit extends Cubit<KycEmailVerificationState> {
     // open and the user can retry without the failure being papered over.
   }
 
-  /// Returns `true` when the wallet was successfully registered with the
-  /// (now-merged) user account. On failure the cubit is already in
-  /// [KycEmailVerificationRegistrationFailure] so the listener can show the
+  /// Returns `true` when the merge can proceed — either the wallet was
+  /// registered (`addWallet` / `alreadyRegistered`), or the account has no
+  /// prior RealUnit registration (`newRegistration`) and is handed back to the
+  /// KYC flow for the full registration form. On failure the cubit is already
+  /// in [KycEmailVerificationRegistrationFailure] so the listener can show the
   /// error to the user.
   Future<bool> _completeRegistration(int generation) async {
     try {
       final info = await _registrationService.getRegistrationInfo();
       if (isClosed || generation != _runGeneration) return false;
+
+      // `registerWallet` (POST /register/wallet) only ADDS a wallet to an
+      // already-existing RealUnit registration, reusing its prior signed data.
+      // When the merged account has no prior registration the API returns
+      // `newRegistration`, and calling register/wallet would fail with
+      // "No RealUnit registration found" (400). The merge is already confirmed
+      // here (the JWT account changed), so hand back to the KYC flow: `KycCubit`
+      // routes `newRegistration` to the full registration form (register/complete).
+      if (info.state == RealUnitRegistrationState.newRegistration) {
+        return true;
+      }
+
+      // For addWallet / alreadyRegistered the API always provides userData; a
+      // null here is a genuine anomaly the user should retry / report.
       if (info.realUnitUserDataDto == null) {
-        // Backend race: the auth service reports the merged account while the
-        // user-data service hasn't propagated yet. Surface as a recoverable
-        // failure so the user can retry by tapping the confirmation button
-        // again — by then propagation will usually have completed, and the
-        // retry path skips the auth-side check thanks to `_mergeDetected`.
-        developer.log(
-          'getRegistrationInfo returned null realUnitUserDataDto after merge',
-        );
+        developer.log('Unexpected null userData for registration state ${info.state}');
         emit(const KycEmailVerificationRegistrationFailure());
         return false;
       }

lib/screens/kyc/steps/email/kyc_email_page.dart

@@ -80,12 +80,11 @@ class _KycEmailFormState extends State<KycEmailForm> {
               ),
             );
             if (isConfirmed == true && context.mounted) {
-              // A successful merge confirmation already registered this
-              // wallet via `KycEmailVerificationCubit._completeRegistration`
-              // → `RealUnitRegistrationService.registerWallet`. The next
-              // `checkKyc()` re-fetches `getRegistrationInfo`, sees
-              // `AlreadyRegistered`, and routes forward — no local sign-gate
-              // flag needed.
+              // The merge is confirmed. `checkKyc()` re-fetches
+              // `getRegistrationInfo` and routes by state: AddWallet /
+              // AlreadyRegistered were already registered inline by
+              // `KycEmailVerificationCubit`; NewRegistration (no prior RealUnit
+              // registration) is routed to the full registration form here.
               context.read<KycCubit>().checkKyc();
             }
           }

test/screens/kyc/steps/email/kyc_email_verification_cubit_test.dart

@@ -4,9 +4,9 @@ import 'package:bloc_test/bloc_test.dart';
 import 'package:flutter_test/flutter_test.dart';
 import 'package:mocktail/mocktail.dart';
 import 'package:realunit_wallet/packages/service/dfx/dfx_auth_service.dart';
+import 'package:realunit_wallet/packages/service/dfx/models/registration/kyc/kyc_personal_data.dart';
 import 'package:realunit_wallet/packages/service/dfx/models/registration/registration_status.dart';
 import 'package:realunit_wallet/packages/service/dfx/models/user/dto/real_unit_user_data_dto.dart';
-import 'package:realunit_wallet/packages/service/dfx/models/registration/kyc/kyc_personal_data.dart';
 import 'package:realunit_wallet/packages/service/dfx/models/wallet/real_unit_registration_info_dto.dart';
 import 'package:realunit_wallet/packages/service/dfx/models/wallet/real_unit_registration_state.dart';
 import 'package:realunit_wallet/packages/service/dfx/real_unit_registration_service.dart';
@@ -124,8 +124,9 @@ void main() {
     );
 
     blocTest<KycEmailVerificationCubit, KycEmailVerificationState>(
-      'changed account id but no userData → RegistrationFailure, no Success '
-      '(propagation race: user can retry by tapping the confirm button again)',
+      'changed account id + NewRegistration → Success (hands off to the KYC flow), '
+      'no registerWallet — the merged account has no prior RealUnit registration '
+      'so register/wallet would 400 "No RealUnit registration found"',
       setUp: () {
         final tokens = [_fakeJwt(1), _fakeJwt(2)];
         var i = 0;
@@ -141,7 +142,33 @@ void main() {
       act: (c) => c.checkEmailVerification(),
       expect: () => [
         isA<KycEmailVerificationLoading>(),
-        isA<KycEmailVerificationRegistrationFailure>(),
+        isA<KycEmailVerificationSuccess>(),
+      ],
+      verify: (_) {
+        verifyNever(() => registrationService.registerWallet(any()));
+      },
+    );
+
+    blocTest<KycEmailVerificationCubit, KycEmailVerificationState>(
+      'NewRegistration WITH userData present still hands off (Success), no '
+      'registerWallet — reproduces the real bug: existing KYC data makes '
+      'userData non-null while the account still has no RealUnit registration',
+      setUp: () {
+        final tokens = [_fakeJwt(1), _fakeJwt(2)];
+        var i = 0;
+        when(() => auth.getAuthToken()).thenAnswer((_) async => tokens[i++]);
+        when(() => registrationService.getRegistrationInfo()).thenAnswer(
+          (_) async => RealUnitRegistrationInfoDto(
+            state: RealUnitRegistrationState.newRegistration,
+            realUnitUserDataDto: _userData,
+          ),
+        );
+      },
+      build: build,
+      act: (c) => c.checkEmailVerification(),
+      expect: () => [
+        isA<KycEmailVerificationLoading>(),
+        isA<KycEmailVerificationSuccess>(),
       ],
       verify: (_) {
         verifyNever(() => registrationService.registerWallet(any()));
@@ -175,32 +202,29 @@ void main() {
     );
 
     blocTest<KycEmailVerificationCubit, KycEmailVerificationState>(
-      'retry after null-userData race: second call skips account-id check '
-      '(propagation completed → registerWallet succeeds → Success)',
+      'retry after a transient registerWallet failure (AddWallet): the second '
+      'call skips the account-id check via _mergeDetected → registerWallet '
+      'succeeds → Success',
       setUp: () {
-        // First call: account-id changes, userData not yet propagated.
-        // Second call: same account-id (already merged), userData now present.
-        // Without the `_mergeDetected` short-circuit the second call would
-        // hit the same-account-id guard and emit Failure ("email not yet
-        // confirmed") — verifying the retry path works.
-        final tokens = [_fakeJwt(1), _fakeJwt(2), _fakeJwt(2), _fakeJwt(2)];
+        // First call detects the merge (account 1 → 2). The second call must
+        // skip the same-account-id guard (which would otherwise emit Failure,
+        // "email not yet confirmed") thanks to `_mergeDetected`, and retry the
+        // AddWallet registration.
+        final tokens = [_fakeJwt(1), _fakeJwt(2)];
         var i = 0;
         when(() => auth.getAuthToken()).thenAnswer((_) async => tokens[i++]);
-        var walletStatusCallCount = 0;
-        when(() => registrationService.getRegistrationInfo()).thenAnswer((_) async {
-          walletStatusCallCount++;
-          return walletStatusCallCount == 1
-              ? RealUnitRegistrationInfoDto(
-                  state: RealUnitRegistrationState.newRegistration,
-                  realUnitUserDataDto: null,
-                )
-              : RealUnitRegistrationInfoDto(
-                  state: RealUnitRegistrationState.addWallet,
-                  realUnitUserDataDto: _userData,
-                );
+        when(() => registrationService.getRegistrationInfo()).thenAnswer(
+          (_) async => RealUnitRegistrationInfoDto(
+            state: RealUnitRegistrationState.addWallet,
+            realUnitUserDataDto: _userData,
+          ),
+        );
+        var calls = 0;
+        when(() => registrationService.registerWallet(any())).thenAnswer((_) async {
+          calls++;
+          if (calls == 1) throw Exception('transient');
+          return RegistrationStatus.completed;
         });
-        when(() => registrationService.registerWallet(any()))
-            .thenAnswer((_) async => RegistrationStatus.completed);
       },
       build: build,
       act: (c) async {
@@ -214,7 +238,7 @@ void main() {
         isA<KycEmailVerificationSuccess>(),
       ],
       verify: (_) {
-        verify(() => registrationService.registerWallet(_userData)).called(1);
+        verify(() => registrationService.registerWallet(_userData)).called(2);
       },
     );
   });