[PM-8952] Implemented minimum length for pin (#1522)

Author: LRNcardozoWDF

BitwardenShared/Core/Platform/Utilities/Constants.swift

@@ -70,6 +70,9 @@ extension Constants {
     /// A default value for the minimum number of characters required when creating a password.
     static let minimumPasswordCharacters = 12
 
+    /// The minimum length when setting a pin.
+    static let minimumPinLength = 4
+
     /// The minimum number of minutes before allowing the vault to sync again.
     static let minimumSyncInterval: TimeInterval = 30 * 60 // 30 minutes
 

BitwardenShared/UI/Auth/Extensions/Alert+Auth.swift

@@ -1,3 +1,4 @@
+import BitwardenKit
 import Foundation
 
 // MARK: - Alert+Auth
@@ -322,14 +323,20 @@ extension Alert {
     ) -> Alert {
         Alert(
             title: Localizations.enterPIN,
-            message: settingUp ? Localizations.setPINDescription : Localizations.verifyPIN,
+            message: settingUp
+                ? Localizations.yourPINMustBeAtLeastXCharactersDescriptionLong(Constants.minimumPinLength)
+                : Localizations.verifyPIN,
             alertActions: [
                 AlertAction(
                     title: Localizations.submit,
                     style: .default,
                     handler: { _, alertTextFields in
                         guard let pin = alertTextFields.first(where: { $0.id == "pin" })?.text else { return }
                         await completion(pin)
+                    },
+                    shouldEnableAction: { textFields in
+                        guard let pin = textFields.first(where: { $0.id == "pin" })?.text else { return false }
+                        return pin.count >= Constants.minimumPinLength
                     }
                 ),
                 AlertAction(title: Localizations.cancel, style: .cancel, handler: { _, _ in

BitwardenShared/UI/Auth/Extensions/AlertAuthTests.swift

@@ -1,3 +1,4 @@
+import BitwardenKit
 import XCTest
 
 @testable import BitwardenShared
@@ -177,7 +178,33 @@ class AlertAuthTests: BitwardenTestCase {
         XCTAssertEqual(subject.alertActions.count, 2)
         XCTAssertEqual(subject.preferredStyle, .alert)
         XCTAssertEqual(subject.title, Localizations.enterPIN)
-        XCTAssertEqual(subject.message, Localizations.setPINDescription)
+        XCTAssertEqual(subject.message,
+                       Localizations.yourPINMustBeAtLeastXCharactersDescriptionLong(Constants.minimumPinLength))
+    }
+
+    /// `enterPINCode(completion:settingUp:)` disables the "Submit" button when the text field is empty,
+    /// and enables it dynamically when the user enters a pin with the minimum length.
+    @MainActor
+    func test_enterPINCode_enablesSubmitButtonWhenMinimumLengthPinIsEntered() async throws {
+        let alert = Alert.enterPINCode(settingUp: true) { _ in }
+        let controller = alert.createAlertController()
+
+        let pinWithMinimumLength = String(repeating: "1", count: Constants.minimumPinLength)
+
+        let uiTextField = try XCTUnwrap(controller.textFields?.first)
+        let submitAction = try XCTUnwrap(
+            controller.actions.first(where: { $0.title == Localizations.submit })
+        )
+
+        uiTextField.text = String(repeating: "1", count: Constants.minimumPinLength - 1)
+        alert.alertTextFields.first?.textChanged(in: uiTextField)
+
+        XCTAssertFalse(submitAction.isEnabled)
+
+        uiTextField.text = pinWithMinimumLength
+        alert.alertTextFields.first?.textChanged(in: uiTextField)
+
+        XCTAssertTrue(submitAction.isEnabled)
     }
 
     /// `enterPINCode(completion:settingUp:)` constructs an `Alert`

BitwardenShared/UI/Platform/Application/Support/Localizations/en.lproj/Localizable.strings

@@ -435,7 +435,6 @@
 "Unlock" = "Unlock";
 "UnlockVault" = "Unlock vault";
 "ThirtyMinutes" = "30 minutes";
-"SetPINDescription" = "Set your PIN code for unlocking Bitwarden. Your PIN settings will be reset if you ever fully log out of the application.";
 "LoggedInAsOn" = "Logged in as %1$@ on %2$@.";
 "VaultLockedMasterPassword" = "Your vault is locked. Verify your master password to continue.";
 "VaultLockedPIN" = "Your vault is locked. Verify your PIN code to continue.";
@@ -1167,3 +1166,4 @@
 "ExpiresInXDays" = "Expires in %1$@ days";
 "DateRangeXToY" = "%1$@ to %2$@";
 "SelfHostServerURL" = "Self-host server URL";
+"YourPINMustBeAtLeastXCharactersDescriptionLong" = "Your PIN must be at least %1$@ characters. Your PIN settings will be reset if you ever fully log out of the application.";