Remove unnecessary leading digits in phone number.

2026-07-30 01:43:46 +01:00 · 2026-07-22 12:47:56 -04:00
parent dfe6ae812d
commit 7a2c084b49
2 changed files with 99 additions and 3 deletions
@@ -117,7 +117,8 @@ class PhoneNumberEntryViewModel(
        stateEmitter(applyPhoneNumberChanged(state, event.oldValue, event.newValue))
      }
      is PhoneNumberEntryScreenEvents.NextClicked -> {
-        stateEmitter(state.copy(dialogs = state.dialogs.copy(confirmNumber = true)))
+        val normalized = state.withNormalizedNationalNumber()
+        stateEmitter(normalized.copy(dialogs = normalized.dialogs.copy(confirmNumber = true)))
      }
      is PhoneNumberEntryScreenEvents.PhoneNumberCancelled -> {
        stateEmitter(state.copy(dialogs = state.dialogs.copy(confirmNumber = false)))
@@ -275,8 +276,8 @@ class PhoneNumberEntryViewModel(
    inputState: PhoneNumberEntryState,
    parentEventEmitter: (RegistrationFlowEvent) -> Unit
  ): PhoneNumberEntryState {
-    val e164 = "+${inputState.countryCode}${inputState.nationalNumber}"
-    var state = inputState.copy()
+    var state = inputState.withNormalizedNationalNumber()
+    val e164 = "+${state.countryCode}${state.nationalNumber}"

    // If the user selected a restore option before entering their phone number, navigate to the restore flow
    if (state.pendingRestoreOption != null) {
@@ -891,6 +892,34 @@ class PhoneNumberEntryViewModel(
    return (new.length - prefix - suffix).coerceAtLeast(0)
  }

+  /**
+   * Strips a redundant national trunk prefix from the national number (e.g. the leading 0 a Dutch user habitually
+   * types in "0612345678"), which would otherwise produce a wrong E164 when naively concatenated with the country
+   * code (+310612345678 instead of +31612345678). Leading zeros that are a significant part of the number (e.g.
+   * Italian landlines) are preserved.
+   */
+  private fun PhoneNumberEntryState.withNormalizedNationalNumber(): PhoneNumberEntryState {
+    if (countryCode.isEmpty() || nationalNumber.isEmpty()) {
+      return this
+    }
+
+    val parsedNumber = try {
+      phoneNumberUtil.parse("+$countryCode$nationalNumber", null)
+    } catch (_: NumberParseException) {
+      return this
+    }
+
+    val significantNumber = phoneNumberUtil.getNationalSignificantNumber(parsedNumber)
+    if (significantNumber == nationalNumber || parsedNumber.countryCode.toString() != countryCode) {
+      return this
+    }
+
+    return copy(
+      nationalNumber = significantNumber,
+      formattedNumber = formatNumber(significantNumber)
+    ).withNumberValidity()
+  }
+
  /**
   * Recomputes [PhoneNumberEntryState.isNumberPossible] and [PhoneNumberEntryState.isNumberInvalid] from the current
   * country code and national number. Should be applied to any state that changes either of those fields.
@@ -485,6 +485,73 @@ class PhoneNumberEntryViewModelTest {
    assertThat(state.nationalNumber).isEqualTo("15123456789")
  }

+  // ==================== Trunk Prefix Normalization Tests ====================
+
+  @Test
+  fun `NextClicked strips a redundant leading trunk prefix before showing the confirmation dialog`() = runTest {
+    // Dutch users habitually type their number with the leading national '0' (e.g. 0612345678), which must not end
+    // up in the E164 (+31612345678, not +310612345678).
+    val initialState = PhoneNumberEntryState(regionCode = "NL", countryCode = "31", nationalNumber = "0612345678", formattedNumber = "06 12345678")
+
+    viewModel.applyEvent(initialState, PhoneNumberEntryScreenEvents.NextClicked, parentEventEmitter, stateEmitter)
+
+    assertThat(emittedStates).hasSize(1)
+    val result = emittedStates.last()
+    assertThat(result.nationalNumber).isEqualTo("612345678")
+    assertThat(result.countryCode).isEqualTo("31")
+    assertThat(result.isNumberPossible).isTrue()
+    assertThat(result.dialogs.confirmNumber).isTrue()
+  }
+
+  @Test
+  fun `NextClicked leaves a number without a trunk prefix unchanged`() = runTest {
+    val initialState = PhoneNumberEntryState(regionCode = "US", countryCode = "1", nationalNumber = "5551234567", formattedNumber = "(555) 123-4567")
+
+    viewModel.applyEvent(initialState, PhoneNumberEntryScreenEvents.NextClicked, parentEventEmitter, stateEmitter)
+
+    assertThat(emittedStates).hasSize(1)
+    val result = emittedStates.last()
+    assertThat(result.nationalNumber).isEqualTo("5551234567")
+    assertThat(result.formattedNumber).isEqualTo("(555) 123-4567")
+    assertThat(result.dialogs.confirmNumber).isTrue()
+  }
+
+  @Test
+  fun `NextClicked preserves a leading zero that is a significant part of the number`() = runTest {
+    // Italian landlines include the leading zero as part of the number itself, so it must not be stripped.
+    val initialState = PhoneNumberEntryState(regionCode = "IT", countryCode = "39", nationalNumber = "0612345678", formattedNumber = "06 1234 5678")
+
+    viewModel.applyEvent(initialState, PhoneNumberEntryScreenEvents.NextClicked, parentEventEmitter, stateEmitter)
+
+    assertThat(emittedStates).hasSize(1)
+    val result = emittedStates.last()
+    assertThat(result.nationalNumber).isEqualTo("0612345678")
+    assertThat(result.dialogs.confirmNumber).isTrue()
+  }
+
+  @Test
+  fun `PhoneNumberConfirmed submits the E164 without a redundant leading trunk prefix`() = runTest {
+    val sessionMetadata = createSessionMetadata(requestedInformation = emptyList())
+
+    coEvery { mockRepository.createSession(any()) } returns
+      RequestResult.Success(sessionMetadata)
+    coEvery { mockRepository.requestVerificationCode(any(), any(), any()) } returns
+      RequestResult.Success(sessionMetadata)
+
+    val initialState = PhoneNumberEntryState(
+      regionCode = "NL",
+      countryCode = "31",
+      nationalNumber = "0612345678"
+    )
+
+    viewModel.applyEvent(initialState, PhoneNumberEntryScreenEvents.PhoneNumberConfirmed, parentEventEmitter, stateEmitter)
+
+    coVerify(exactly = 1) { mockRepository.createSession("+31612345678") }
+    assertThat(emittedStates.last().nationalNumber).isEqualTo("612345678")
+    assertThat(emittedEvents.filterIsInstance<RegistrationFlowEvent.E164Chosen>())
+      .isEqualTo(listOf(RegistrationFlowEvent.E164Chosen("+31612345678")))
+  }
+
  // ==================== FullPhoneNumberEntered Tests ====================

  @Test