Pass along style config from MPE to FC

Example/FinancialConnections Example/FinancialConnections Example/Playground/PlaygroundViewModel.swift

@@ -648,6 +648,12 @@ private func PresentPaymentSheet(
     configuration.defaultBillingDetails.email = config.email
     configuration.defaultBillingDetails.phone = config.phone
 
+    switch config.style {
+    case .automatic: configuration.style = .automatic
+    case .alwaysLight: configuration.style = .alwaysLight
+    case .alwaysDark: configuration.style = .alwaysDark
+    }
+
     let isUITest = (ProcessInfo.processInfo.environment["UITesting"] != nil)
     // disable app-to-app for UI tests
     configuration.returnURL = isUITest ? nil : "financial-connections-example://redirect"

StripeCore/StripeCore/Source/Connections Bindings/ElementsSessionContext.swift

@@ -44,13 +44,22 @@ import Foundation
         }
     }
 
+    /// Intermediary object between `PaymentSheet.Configuration.UserInterfaceStyle`
+    /// and `FinancialConnectionsSheet.Configuration.UserInterfaceStyle`.
+    @_spi(STP) @frozen public enum StyleConfig {
+        case automatic
+        case alwaysLight
+        case alwaysDark
+    }
+
     @_spi(STP) public let amount: Int?
     @_spi(STP) public let currency: String?
     @_spi(STP) public let prefillDetails: PrefillDetails?
     @_spi(STP) public let intentId: IntentID?
     @_spi(STP) public let linkMode: LinkMode?
     @_spi(STP) public let billingDetails: BillingDetails?
     @_spi(STP) public let eligibleForIncentive: Bool
+    @_spi(STP) public let styleConfig: StyleConfig?
 
     @_spi(STP) public var billingAddress: BillingAddress? {
         BillingAddress(from: billingDetails)
@@ -70,7 +79,8 @@ import Foundation
         intentId: IntentID? = nil,
         linkMode: LinkMode? = nil,
         billingDetails: BillingDetails? = nil,
-        eligibleForIncentive: Bool = false
+        eligibleForIncentive: Bool = false,
+        styleConfig: StyleConfig? = nil
     ) {
         self.amount = amount
         self.currency = currency
@@ -79,6 +89,7 @@ import Foundation
         self.linkMode = linkMode
         self.billingDetails = billingDetails
         self.eligibleForIncentive = eligibleForIncentive
+        self.styleConfig = styleConfig
     }
 }
 

StripeFinancialConnections/StripeFinancialConnections/Source/FinancialConnectionsSDK/FinancialConnectionsSDKImplementation.swift

@@ -32,6 +32,16 @@ public class FinancialConnectionsSDKImplementation: FinancialConnectionsSDKInter
         financialConnectionsSheet.apiClient = apiClient
         financialConnectionsSheet.elementsSessionContext = elementsSessionContext
         financialConnectionsSheet.onEvent = onEvent
+
+        var configuration = FinancialConnectionsSheet.Configuration()
+        if let styleConfig = elementsSessionContext?.styleConfig {
+            switch styleConfig {
+            case .automatic: configuration.style = .automatic
+            case .alwaysLight: configuration.style = .alwaysLight
+            case .alwaysDark: configuration.style = .alwaysDark
+            }
+        }
+        financialConnectionsSheet.configuration = configuration
         // Captures self explicitly until the callback is invoked
         financialConnectionsSheet.present(
             from: presentingViewController,

StripeFinancialConnections/StripeFinancialConnections/Source/FinancialConnectionsSheet.swift

@@ -48,19 +48,21 @@ final public class FinancialConnectionsSheet {
     @_spi(STP) public struct Configuration {
         /// Style options for colors in Financial Connections.
         @_spi(STP) @frozen public enum UserInterfaceStyle {
-            /// (default) Financial Connections will automatically switch between light and dark mode compatible colors based on device settings.
+            /// Financial Connections will automatically switch between light and dark mode compatible colors based on device settings.
             case automatic
-            /// Financial Connections will always use colors appropriate for light mode UI.
+
+            /// (default) Financial Connections will always use colors appropriate for light mode UI.
             case alwaysLight
+
             /// Financial Connections will always use colors appropriate for dark mode UI.
             case alwaysDark
 
             /// Applies the specified user interface style to the given view controller.
             func configure(_ viewController: UIViewController?) {
-                guard let viewController else { return }
                 guard ExperimentStore.shared.supportsDynamicStyle else {
                     return
                 }
+                guard let viewController else { return }
 
                 switch self {
                 case .automatic:

StripeFinancialConnections/StripeFinancialConnections/Source/Native/NativeFlowController.swift

@@ -1698,6 +1698,7 @@ private func CreatePaneViewController(
             )
     }
 
+    // Applies the style configuration to each view controller.
     dataManager.configuration.style.configure(viewController)
     return viewController
 }

StripeFinancialConnections/StripeFinancialConnections/Source/Native/Shared/ExperimentStore.swift

@@ -7,7 +7,8 @@
 
 import Foundation
 
-/// Internal store to access exoerimental features,
+/// Internal singleton store to access experimental features.
+/// Enabling any of these might result in unexpected behavior.
 @_spi(STP) public class ExperimentStore {
     @_spi(STP) public static let shared = ExperimentStore()
 

StripeFinancialConnections/StripeFinancialConnectionsTests/FinancialConnectionsSheetTests.swift

@@ -52,8 +52,9 @@ class FinancialConnectionsSheetTests: XCTestCase {
             apiClient: mockApiClient,
             analyticsClientV1: mockAnalyticsClient,
             clientSecret: "test",
-            elementsSessionContext: nil,
             returnURL: nil,
+            configuration: .init(),
+            elementsSessionContext: nil,
             publishableKey: "test",
             stripeAccount: nil
         )

StripePaymentSheet/StripePaymentSheet/Source/PaymentSheet/Link/LinkPaymentController.swift

@@ -314,14 +314,23 @@ import UIKit
             )
         )
 
+        let styleConfig: ElementsSessionContext.StyleConfig = {
+            switch configuration.style {
+            case .automatic: return .automatic
+            case .alwaysLight: return .alwaysLight
+            case .alwaysDark: return .alwaysDark
+            }
+        }()
+
         return ElementsSessionContext(
             amount: mode.amount,
             currency: mode.currency,
             prefillDetails: makePrefillDetails(),
             intentId: nil,
             linkMode: nil,
             billingDetails: billingDetails,
-            eligibleForIncentive: false
+            eligibleForIncentive: false,
+            styleConfig: styleConfig
         )
     }
 

StripePaymentSheet/StripePaymentSheet/Source/PaymentSheet/ViewControllers/PaymentMethodFormViewController.swift

@@ -275,6 +275,13 @@ extension PaymentMethodFormViewController {
         )
         let linkMode = elementsSession.linkSettings?.linkMode
         let billingDetails = instantDebitsFormElement?.billingDetails
+        let styleConfig: ElementsSessionContext.StyleConfig = {
+            switch configuration.style {
+            case .automatic: return .automatic
+            case .alwaysLight: return .alwaysLight
+            case .alwaysDark: return .alwaysDark
+            }
+        }()
 
         return ElementsSessionContext(
             amount: intent.amount,
@@ -283,7 +290,8 @@ extension PaymentMethodFormViewController {
             intentId: intentId,
             linkMode: linkMode,
             billingDetails: billingDetails,
-            eligibleForIncentive: instantDebitsFormElement?.displayableIncentive != nil
+            eligibleForIncentive: instantDebitsFormElement?.displayableIncentive != nil,
+            styleConfig: styleConfig
         )
     }