fix: limit feedback message length

CHANGELOG.md

@@ -89,6 +89,9 @@
 ### Internal
 
 - Fix `SentrySDK.internal.replay.replayId` returning nil for buffered replays (#8976)
+- Mark the fabricated `mach` and `signal` crash mechanisms as `synthetic` so an Apple crash groups with the identical crash reported by the other Sentry SDKs, and so a mach-caught and a signal-caught report of the same bug no longer split into two issues (#8919)
+- Set `mechanism.handled` to `false` on crash reports that carry no mach context, which previously left it unset (#8919)
+- Prevent managed user feedback from submitting messages longer than 4096 Unicode scalars, and show the limit in the feedback form. (#8973)
 
 ## 9.27.0
 

Sources/Swift/Integrations/UserFeedback/SentryUserFeedbackFormController.swift

@@ -229,14 +229,18 @@ extension SentryUserFeedbackFormController: SentryUserFeedbackFormViewModelDeleg
                 }
             }
 
-            guard case let SentryUserFeedbackFormViewModel.InputError.validationError(missing, _) = error,
-                let errorDescription = error.errorDescription else {
+            guard let errorDescription = error.errorDescription else {
                 SentrySDKLog.warning("Unexpected error type.")
                 presentAlert(message: config.formConfig.unexpectedErrorText, errorCode: 2, info: [NSLocalizedDescriptionKey: "Client error: ."])
                 return
             }
 
-            presentAlert(message: errorDescription, errorCode: 1, info: ["missing_fields": missing, NSLocalizedDescriptionKey: "The user did not complete the feedback form."])
+            switch error {
+            case .validationError(let missing, _):
+                presentAlert(message: errorDescription, errorCode: 1, info: ["missing_fields": missing, NSLocalizedDescriptionKey: "The user did not complete the feedback form."])
+            case .messageTooLong:
+                presentAlert(message: errorDescription, errorCode: 1, info: [NSLocalizedDescriptionKey: errorDescription])
+            }
         }
     }
 
@@ -313,6 +317,7 @@ extension SentryUserFeedbackFormController: UITextViewDelegate {
     /// Updates validation state when the feedback message changes.
     public func textViewDidChange(_ textView: UITextView) {
         viewModel.messageTextViewPlaceholder.isHidden = textView.text != ""
+        viewModel.updateMessageCharacterCount()
         viewModel.updateSubmitButtonAccessibilityHint()
     }
 }

Sources/Swift/Integrations/UserFeedback/SentryUserFeedbackFormViewModel.swift

@@ -13,6 +13,9 @@ protocol SentryUserFeedbackFormViewModelDelegate: NSObjectProtocol {
 
 @objcMembers
 @_spi(Private) public class SentryUserFeedbackFormViewModel: NSObject {
+    // The backend uses Python code-point length, which matches Swift Unicode scalars.
+    static let maxMessageLength = 4_096
+
     let config: SentryUserFeedbackConfiguration
     unowned let controller: SentryUserFeedbackFormController
     weak var delegate: SentryUserFeedbackFormViewModelDelegate?
@@ -126,6 +129,17 @@ protocol SentryUserFeedbackFormViewModelDelegate: NSObjectProtocol {
         textView.accessibilityIdentifier = "io.sentry.feedback.form.message"
         return textView
     }()
+
+    lazy var messageCharacterCountLabel = {
+        let label = UILabel(frame: .zero)
+        label.font = config.theme.scaledFont(style: .caption1)
+        label.adjustsFontForContentSizeCategory = true
+        label.textAlignment = .right
+        label.accessibilityIdentifier = "io.sentry.feedback.form.message-character-count"
+        label.accessibilityTraits.insert(.updatesFrequently)
+        updateMessageCharacterCount(label: label)
+        return label
+    }()
 
     lazy var screenshotImageView = {
         let iv = UIImageView()
@@ -227,6 +241,7 @@ protocol SentryUserFeedbackFormViewModelDelegate: NSObjectProtocol {
 
         let messageAndScreenshotStack = UIStackView(arrangedSubviews: [
             self.messageTextView,
+            self.messageCharacterCountLabel,
             self.addScreenshotButton,
             self.removeScreenshotStack
         ])
@@ -399,6 +414,17 @@ extension SentryUserFeedbackFormViewModel {
         case .failure(let error): submitButton.accessibilityHint = error.errorDescription
         }
     }
+
+    func updateMessageCharacterCount() {
+        updateMessageCharacterCount(label: messageCharacterCountLabel)
+    }
+
+    private func updateMessageCharacterCount(label: UILabel) {
+        let count = messageTextView.text?.unicodeScalars.count ?? 0
+        label.text = "\(count) / \(Self.maxMessageLength)"
+        label.accessibilityLabel = "\(count) of \(Self.maxMessageLength) characters used"
+        label.textColor = count > Self.maxMessageLength ? config.theme.errorColor : config.theme.foreground
+    }
 
     func themeElements() {
         [fullNameTextField, emailTextField].forEach {
@@ -499,7 +525,9 @@ extension SentryUserFeedbackFormViewModel {
         }
 
         // include the message they'll submit
+        var messageLength = 0
         if let message = messageTextView.textOrNil {
+            messageLength = message.unicodeScalars.count
             hint.append("with message: \(message)")
         } else {
             missing.append(config.formConfig.messageLabel.lowercased())
@@ -510,17 +538,24 @@ extension SentryUserFeedbackFormViewModel {
             let result = SentryUserFeedbackFormValidation.failure(InputError.validationError(missingFields: missing, localizedError: localizedError))
             return result
         }
+
+        guard messageLength <= Self.maxMessageLength else {
+            return .failure(.messageTooLong(maximumLength: Self.maxMessageLength))
+        }
 
         return SentryUserFeedbackFormValidation.success(hint.joined(separator: " ").appending("."))
     }
 
     enum InputError: LocalizedError {
         case validationError(missingFields: [String], localizedError: String)
+        case messageTooLong(maximumLength: Int)
 
         var description: String {
             switch self {
             case .validationError(_, let localizedError):
                 return localizedError
+            case .messageTooLong(let maximumLength):
+                return "The description must not exceed \(maximumLength) characters."
             }
         }
 

Tests/SentryTests/Integrations/Feedback/SentryFeedbackTests.swift

@@ -456,6 +456,164 @@ class SentryFeedbackTests: XCTestCase {
         XCTAssertEqual(attachments[2].contentType, "video/mp4")
     }
 
+    func testValidate_whenMessageExceedsMaximumLength_shouldReturnSpecificError() throws {
+        // -- Arrange --
+        let config = SentryUserFeedbackConfiguration()
+        let sut = SentryUserFeedbackFormController(preparedConfig: config, screenshot: nil)
+        sut.viewModel.messageTextView.text = String(repeating: "a", count: 4_097)
+
+        // -- Act --
+        let result = sut.viewModel.validate()
+
+        // -- Assert --
+        guard case .failure(let error) = result else {
+            return XCTFail("Expected an over-limit message to fail validation.")
+        }
+        XCTAssertEqual(error.errorDescription, "The description must not exceed 4096 characters.")
+    }
+
+    func testValidate_whenMessageIsAtMaximumLength_shouldSucceed() {
+        // -- Arrange --
+        let config = SentryUserFeedbackConfiguration()
+        let sut = SentryUserFeedbackFormController(preparedConfig: config, screenshot: nil)
+        sut.viewModel.messageTextView.text = String(repeating: "a", count: 4_096)
+
+        // -- Act --
+        let result = sut.viewModel.validate()
+
+        // -- Assert --
+        guard case .success = result else {
+            return XCTFail("Expected a message at the limit to validate.")
+        }
+    }
+
+    func testValidate_whenDecomposedMessageIsAtMaximumScalarLength_shouldSucceed() {
+        // -- Arrange --
+        let config = SentryUserFeedbackConfiguration()
+        let sut = SentryUserFeedbackFormController(preparedConfig: config, screenshot: nil)
+        sut.viewModel.messageTextView.text = String(repeating: "e\u{301}", count: 2_048)
+
+        // -- Act --
+        let result = sut.viewModel.validate()
+
+        // -- Assert --
+        guard case .success = result else {
+            return XCTFail("Expected 4096 Unicode scalars to validate.")
+        }
+    }
+
+    func testValidate_whenDecomposedMessageExceedsMaximumScalarLength_shouldFail() throws {
+        // -- Arrange --
+        let config = SentryUserFeedbackConfiguration()
+        let sut = SentryUserFeedbackFormController(preparedConfig: config, screenshot: nil)
+        sut.viewModel.messageTextView.text = String(repeating: "e\u{301}", count: 2_048) + "a"
+
+        // -- Act --
+        let result = sut.viewModel.validate()
+
+        // -- Assert --
+        guard case .failure(let error) = result else {
+            return XCTFail("Expected 4097 Unicode scalars to fail validation.")
+        }
+        XCTAssertEqual(error.errorDescription, "The description must not exceed 4096 characters.")
+    }
+
+    func testValidate_whenRequiredFieldsAreMissingAndMessageIsTooLong_shouldReportMissingFields() throws {
+        // -- Arrange --
+        let config = SentryUserFeedbackConfiguration()
+        config.formConfig.isNameRequired = true
+        config.formConfig.isEmailRequired = true
+        let sut = SentryUserFeedbackFormController(preparedConfig: config, screenshot: nil)
+        sut.viewModel.messageTextView.text = String(repeating: "a", count: 4_097)
+
+        // -- Act --
+        let result = sut.viewModel.validate()
+
+        // -- Assert --
+        guard case .failure(let error) = result else {
+            return XCTFail("Expected missing required fields to fail validation.")
+        }
+        XCTAssertEqual(error.errorDescription, "You must provide all required information before submitting. Please check the following fields: name and email.")
+    }
+
+    func testMessageCharacterCount_whenTextChanges_shouldCountUnicodeScalars() {
+        // -- Arrange --
+        let config = SentryUserFeedbackConfiguration()
+        let sut = SentryUserFeedbackFormController(preparedConfig: config, screenshot: nil)
+        sut.viewModel.messageTextView.text = "e\u{301}"
+
+        // -- Act --
+        sut.textViewDidChange(sut.viewModel.messageTextView)
+
+        // -- Assert --
+        XCTAssertEqual(sut.viewModel.messageCharacterCountLabel.text, "2 / 4096")
+        XCTAssertEqual(sut.viewModel.messageCharacterCountLabel.accessibilityLabel, "2 of 4096 characters used")
+        XCTAssertTrue(sut.viewModel.messageCharacterCountLabel.accessibilityTraits.contains(.updatesFrequently))
+        XCTAssertEqual(sut.viewModel.messageCharacterCountLabel.textColor, config.theme.foreground)
+    }
+
+    func testMessageCharacterCount_whenMessageExceedsMaximumLength_shouldUseErrorColor() {
+        // -- Arrange --
+        let config = SentryUserFeedbackConfiguration()
+        let sut = SentryUserFeedbackFormController(preparedConfig: config, screenshot: nil)
+        sut.viewModel.messageTextView.text = String(repeating: "a", count: 4_097)
+
+        // -- Act --
+        sut.textViewDidChange(sut.viewModel.messageTextView)
+
+        // -- Assert --
+        XCTAssertEqual(sut.viewModel.messageCharacterCountLabel.text, "4097 / 4096")
+        XCTAssertEqual(sut.viewModel.messageCharacterCountLabel.textColor, config.theme.errorColor)
+    }
+
+    func testMessageCharacterCount_whenTextIsNil_shouldShowZero() {
+        // -- Arrange --
+        let config = SentryUserFeedbackConfiguration()
+        let sut = SentryUserFeedbackFormController(preparedConfig: config, screenshot: nil)
+        sut.viewModel.messageTextView.text = nil
+
+        // -- Act --
+        sut.viewModel.updateMessageCharacterCount()
+
+        // -- Assert --
+        XCTAssertEqual(sut.viewModel.messageCharacterCountLabel.text, "0 / 4096")
+    }
+
+    func testMessageCharacterCount_whenFontFamilyConfigured_shouldUseThemeFont() {
+        // -- Arrange --
+        let config = SentryUserFeedbackConfiguration()
+        config.theme.fontFamily = "Helvetica"
+
+        // -- Act --
+        let sut = SentryUserFeedbackFormController(preparedConfig: config, screenshot: nil)
+
+        // -- Assert --
+        XCTAssertEqual(sut.viewModel.messageCharacterCountLabel.font.familyName, "Helvetica")
+    }
+
+#if !targetEnvironment(macCatalyst)
+    func testSubmitFeedback_whenMessageExceedsMaximumLength_shouldPresentSpecificError() throws {
+        // -- Arrange --
+        let config = SentryUserFeedbackConfiguration()
+        config.animations = false
+        let sut = SentryUserFeedbackFormController(preparedConfig: config, screenshot: nil)
+        sut.viewModel.messageTextView.text = String(repeating: "a", count: 4_097)
+        let window = UIWindow(windowScene: Self.mockWindowScene)
+        window.rootViewController = sut
+        window.makeKeyAndVisible()
+        addTeardownBlock { [window] in
+            window.isHidden = true
+        }
+
+        // -- Act --
+        sut.submitFeedback()
+
+        // -- Assert --
+        let alert = try XCTUnwrap(sut.presentedViewController as? UIAlertController)
+        XCTAssertEqual(alert.message, "The description must not exceed 4096 characters.")
+    }
+#endif
+
     private let inputCombinations: [FeedbackTestCase] = [
         // base case: don't require name or email, don't input a name or email, don't input a message or screenshot
         (config: (requiresName: false, requiresEmail: false, nameInput: nil, emailInput: nil, messageInput: nil, includeScreenshot: false), shouldValidate: false, expectedSubmitButtonAccessibilityHint: "You must provide all required information before submitting. Please check the following field: description."),