fix(auth): preserve phone identity when step payload carries bound email

tests/auto-run-step6-restart.test.js

@@ -83,6 +83,65 @@ const defaultStepDefinitions = {
   10: { key: 'platform-verify' },
 };
 
+const PHONE_IDENTITY_STATE_KEYS = [
+  'phoneNumber',
+  'signupPhoneNumber',
+  'signupPhoneActivation',
+  'signupPhoneCompletedActivation',
+  'signupPhoneVerificationRequestedAt',
+  'signupPhoneVerificationPurpose',
+  'accountIdentifierType',
+  'accountIdentifier',
+];
+
+function createDownstreamResetHarness(stepKey = '') {
+  return new Function(`
+function getStepExecutionKeyForState() {
+  return ${JSON.stringify(stepKey)};
+}
+${extractFunction('getDownstreamStateResets')}
+return { getDownstreamStateResets };
+`)();
+}
+
+test('downstream restarts after account creation preserve phone signup identity fields', () => {
+  const numericResetHarness = createDownstreamResetHarness('');
+  const stepKeyResetHarnesses = [
+    createDownstreamResetHarness('oauth-login'),
+    createDownstreamResetHarness('fetch-login-code'),
+    createDownstreamResetHarness('confirm-oauth'),
+  ];
+  const phoneState = {
+    accountIdentifierType: 'phone',
+    accountIdentifier: '+447780579093',
+    signupPhoneNumber: '+447780579093',
+    signupPhoneActivation: { activationId: 'active', phoneNumber: '+447780579093' },
+    signupPhoneCompletedActivation: { activationId: 'done', phoneNumber: '+447780579093' },
+  };
+
+  for (const step of [5, 6, 7, 8, 9]) {
+    const resets = numericResetHarness.getDownstreamStateResets(step, phoneState);
+    for (const key of PHONE_IDENTITY_STATE_KEYS) {
+      assert.equal(
+        Object.prototype.hasOwnProperty.call(resets, key),
+        false,
+        `step ${step} reset must not clear ${key}`
+      );
+    }
+  }
+
+  for (const harness of stepKeyResetHarnesses) {
+    const resets = harness.getDownstreamStateResets(10, phoneState);
+    for (const key of PHONE_IDENTITY_STATE_KEYS) {
+      assert.equal(
+        Object.prototype.hasOwnProperty.call(resets, key),
+        false,
+        `${key} must not be cleared by step-key reset`
+      );
+    }
+  }
+});
+
 function createHarness(options = {}) {
   const {
     startStep = 7,

tests/background-message-router-step2-skip.test.js

@@ -14,6 +14,7 @@ function createRouter(overrides = {}) {
     broadcasts: [],
     balanceRefreshes: [],
     emailStates: [],
+    persistedRegistrationEmails: [],
     signupPhoneStates: [],
     signupPhoneSilentStates: [],
     finalizePayloads: [],
@@ -123,6 +124,9 @@ function createRouter(overrides = {}) {
       events.emailStates.push(email);
     },
     setEmailStateSilently: async () => {},
+    persistRegistrationEmailState: async (state, email, options) => {
+      events.persistedRegistrationEmails.push({ state, email, options });
+    },
     setSignupPhoneState: async (phoneNumber) => {
       events.signupPhoneStates.push(phoneNumber);
     },
@@ -206,14 +210,38 @@ test('message router clears stale signup phone runtime when step 2 resolves emai
   });
 
   assert.deepStrictEqual(events.emailStates, ['user@example.com']);
-  assert.deepStrictEqual(events.signupPhoneSilentStates, [null]);
-  assert.ok(events.stateUpdates.some((updates) => (
-    updates.accountIdentifierType === 'email'
-    && updates.accountIdentifier === 'user@example.com'
-    && updates.signupPhoneNumber === ''
-    && updates.signupPhoneActivation === null
-    && updates.signupPhoneCompletedActivation === null
-  )));
+  assert.deepStrictEqual(events.signupPhoneSilentStates, []);
+  assert.deepStrictEqual(events.stateUpdates, []);
+});
+
+test('message router preserves phone signup identity when step payload only reports registration email', async () => {
+  const { router, events } = createRouter({
+    state: {
+      stepStatuses: { 3: 'pending' },
+      accountIdentifierType: 'phone',
+      accountIdentifier: '+66959916439',
+      signupPhoneNumber: '+66959916439',
+      signupPhoneActivation: { activationId: 'active', phoneNumber: '+66959916439' },
+    },
+  });
+
+  await router.handleStepData(3, {
+    email: 'bound@example.com',
+    signupVerificationRequestedAt: 123456,
+  });
+
+  assert.deepStrictEqual(events.emailStates, []);
+  assert.equal(events.persistedRegistrationEmails.length, 1);
+  assert.equal(events.persistedRegistrationEmails[0].email, 'bound@example.com');
+  assert.deepStrictEqual(events.persistedRegistrationEmails[0].options, {
+    source: 'step_identity',
+    preserveAccountIdentity: true,
+  });
+  assert.equal(events.persistedRegistrationEmails[0].state.signupPhoneNumber, '+66959916439');
+  assert.equal(events.persistedRegistrationEmails[0].state.accountIdentifierType, 'phone');
+  assert.equal(events.signupPhoneSilentStates.length, 0);
+  assert.ok(!events.stateUpdates.some((updates) => updates.signupPhoneNumber === ''));
+  assert.ok(events.stateUpdates.some((updates) => updates.signupVerificationRequestedAt === 123456));
 });
 
 test('message router does not overwrite a completed step 3 when step 2 is replayed', async () => {