fix(onboarding): prevent duplicate wallet creation tasks

Author: reez

BDKSwiftExampleWallet/View Model/OnboardingViewModel.swift

@@ -128,35 +128,34 @@ class OnboardingViewModel: ObservableObject {
 
     func createWallet() {
         // Check if wallet already exists
-        if let existingBackup = try? bdkClient.getBackupInfo() {
-            Task { @MainActor in
-                self.isOnboarding = false
-            }
+        if (try? bdkClient.getBackupInfo()) != nil {
+            self.isOnboarding = false
             return
         }
 
         guard !isCreatingWallet else {
             return
         }
 
-        Task { @MainActor in
-            self.isCreatingWallet = true
-        }
+        self.isCreatingWallet = true
+        let words = self.words
+        let isDescriptor = self.isDescriptor
+        let isXPub = self.isXPub
 
         Task {
             do {
-                if WifParser.extract(from: self.words) != nil {
+                if WifParser.extract(from: words) != nil {
                     throw AppError.generic(
                         message:
                             "WIF is for sweep, not wallet creation. Open an existing wallet and use Send > Scan/Paste to sweep it."
                     )
                 }
-                if self.isDescriptor {
-                    try self.bdkClient.createWalletFromDescriptor(self.words)
-                } else if self.isXPub {
-                    try self.bdkClient.createWalletFromXPub(self.words)
+                if isDescriptor {
+                    try self.bdkClient.createWalletFromDescriptor(words)
+                } else if isXPub {
+                    try self.bdkClient.createWalletFromXPub(words)
                 } else {
-                    try self.bdkClient.createWalletFromSeed(self.words)
+                    try self.bdkClient.createWalletFromSeed(words)
                 }
                 await MainActor.run {
                     self.isCreatingWallet = false

BDKSwiftExampleWalletTests/View Model/BDKSwiftExampleWalletOnboardingViewModelTests.swift

@@ -0,0 +1,83 @@
+//
+//  BDKSwiftExampleWalletOnboardingViewModelTests.swift
+//  BDKSwiftExampleWalletTests
+//
+//  Created by Codex on 4/9/26.
+//
+
+import Foundation
+import XCTest
+
+@testable import BDKSwiftExampleWallet
+
+final class BDKSwiftExampleWalletOnboardingViewModelTests: XCTestCase {
+    private enum TestOnboardingError: Error {
+        case noBackup
+    }
+
+    private func makeBDKClient(
+        createWalletFromSeed: @escaping (String?) throws -> Void,
+        getBackupInfo: @escaping () throws -> BackupInfo = { throw TestOnboardingError.noBackup }
+    ) -> BDKClient {
+        BDKClient(
+            loadWallet: BDKClient.mock.loadWallet,
+            deleteWallet: BDKClient.mock.deleteWallet,
+            createWalletFromSeed: createWalletFromSeed,
+            createWalletFromDescriptor: BDKClient.mock.createWalletFromDescriptor,
+            createWalletFromXPub: BDKClient.mock.createWalletFromXPub,
+            getBalance: BDKClient.mock.getBalance,
+            transactions: BDKClient.mock.transactions,
+            listUnspent: BDKClient.mock.listUnspent,
+            syncWithInspector: BDKClient.mock.syncWithInspector,
+            fullScanWithInspector: BDKClient.mock.fullScanWithInspector,
+            getAddress: BDKClient.mock.getAddress,
+            send: BDKClient.mock.send,
+            sweepWif: BDKClient.mock.sweepWif,
+            calculateFee: BDKClient.mock.calculateFee,
+            calculateFeeRate: BDKClient.mock.calculateFeeRate,
+            sentAndReceived: BDKClient.mock.sentAndReceived,
+            txDetails: BDKClient.mock.txDetails,
+            buildTransaction: BDKClient.mock.buildTransaction,
+            getBackupInfo: getBackupInfo,
+            needsFullScan: BDKClient.mock.needsFullScan,
+            setNeedsFullScan: BDKClient.mock.setNeedsFullScan,
+            getNetwork: BDKClient.mock.getNetwork,
+            getEsploraURL: BDKClient.mock.getEsploraURL,
+            updateNetwork: BDKClient.mock.updateNetwork,
+            updateEsploraURL: BDKClient.mock.updateEsploraURL,
+            getAddressType: BDKClient.mock.getAddressType,
+            updateAddressType: BDKClient.mock.updateAddressType,
+            getClientType: BDKClient.mock.getClientType,
+            updateClientType: BDKClient.mock.updateClientType
+        )
+    }
+
+    @MainActor
+    func testCreateWalletIgnoresRepeatedCallsWhileCreationInProgress() async {
+        let started = expectation(description: "wallet creation started")
+        let created = XCTNSNotificationExpectation(name: .walletCreated)
+        let unblockCreation = DispatchSemaphore(value: 0)
+        var createCallCount = 0
+
+        let viewModel = OnboardingViewModel(
+            bdkClient: makeBDKClient(createWalletFromSeed: { _ in
+                createCallCount += 1
+                started.fulfill()
+                unblockCreation.wait()
+            })
+        )
+        viewModel.words =
+            "abandon ability able about above absent absorb abstract absurd abuse access accident"
+
+        viewModel.createWallet()
+        await fulfillment(of: [started], timeout: 1.0)
+        viewModel.createWallet()
+
+        XCTAssertTrue(viewModel.isCreatingWallet)
+        XCTAssertEqual(createCallCount, 1)
+
+        unblockCreation.signal()
+        await fulfillment(of: [created], timeout: 1.0)
+        XCTAssertFalse(viewModel.isCreatingWallet)
+    }
+}