Fix resume response handling.

Author: antrix1989

IdentityCore/src/webview/operations/ios/MSIDSwitchBrowserOperation.m

@@ -102,6 +102,7 @@ - (void)invokeWithRequestParameters:(nonnull MSIDInteractiveTokenRequestParamete
 
         NSError *localError;
         __auto_type response = [webRequestConfiguration responseWithResultURL:callbackURL factory:oauthFactory.webviewFactory context:requestParameters error:&localError];
+        response.parentResponse = self.switchBrowserResponse;
 
         if (localError)
         {

IdentityCore/src/webview/operations/ios/MSIDSwitchBrowserResumeOperation.m

@@ -62,6 +62,19 @@ - (nullable instancetype)initWithResponse:(MSIDWebviewResponse *)response
         }
 
         _switchBrowserResumeResponse = (MSIDSwitchBrowserResumeResponse *)response;
+        
+        __auto_type parentResponse = _switchBrowserResumeResponse.parentResponse;
+        if (![parentResponse isKindOfClass:MSIDSwitchBrowserResponse.class])
+        {
+            NSString *errorMsg = [NSString stringWithFormat:@"Parent response of type %@ is required for creating %@", MSIDSwitchBrowserResponse.class, self.class];
+            MSID_LOG_WITH_CTX(MSIDLogLevelError, nil, @"%@", errorMsg);
+            if (error)
+            {
+                *error = MSIDCreateError(MSIDErrorDomain, MSIDErrorInternal, errorMsg, nil, nil, nil, nil, nil, NO);
+            }
+            
+            return nil;
+        }
     }
 
     return self;

IdentityCore/src/webview/response/MSIDWebviewResponse.h

@@ -35,6 +35,11 @@
 @property (atomic, readonly) NSURL *url;
 @property (nonatomic, class, readonly) NSString *operation;
 
+/// Enables tracking of web response chains.
+/// For example, it is used in DUNA CBA flow to check that "swich_browser_resume" response
+/// was created as a result of "switch_browser" response.
+@property (nonatomic) MSIDWebviewResponse *parentResponse;
+
 - (instancetype)initWithURL:(NSURL *)url
                     context:(id<MSIDRequestContext>)context
                       error:(NSError *__autoreleasing*)error;

IdentityCore/tests/MSIDSwitchBrowserResumeOperationTest.swift

@@ -28,8 +28,15 @@ import XCTest
 final class MSIDSwitchBrowserResumeOperationTest: XCTestCase 
 {
     lazy var validSwitchBrowserResumeResponse: MSIDSwitchBrowserResumeResponse? = {
-        let url = URL(string: "msauth.com.microsoft.msaltestapp://auth/switch_browser_resume?action_uri=some_uri&code=some_code")!
-        return try? MSIDSwitchBrowserResumeResponse(url: url, redirectUri: "msauth.com.microsoft.msaltestapp://auth", context: nil)
+        
+        let switchUrl = URL(string: "msauth.com.microsoft.msaltestapp://auth/switch_browser?action_uri=some_uri&code=some_code")!
+        let switchBrowserResponse = try? MSIDSwitchBrowserResponse(url: switchUrl, redirectUri: "msauth.com.microsoft.msaltestapp://auth",  context: nil)
+        
+        let resumeUrl = URL(string: "msauth.com.microsoft.msaltestapp://auth/switch_browser_resume?action_uri=some_uri&code=some_code")!
+        let resumeResponse = try? MSIDSwitchBrowserResumeResponse(url: resumeUrl, redirectUri: "msauth.com.microsoft.msaltestapp://auth", context: nil)
+        resumeResponse?.parent = switchBrowserResponse
+        
+        return resumeResponse
     }()
 
     override func setUpWithError() throws
@@ -51,6 +58,19 @@ final class MSIDSwitchBrowserResumeOperationTest: XCTestCase
 
         XCTAssertNotNil(operation)
     }
+    
+    func testInit_whenNoParentResponse_shouldReturnNil() throws
+    {
+        XCTAssertNotNil(self.validSwitchBrowserResumeResponse)
+        guard let response = self.validSwitchBrowserResumeResponse else { return }
+        response.parent = nil
+        
+        XCTAssertThrowsError(try MSIDSwitchBrowserResumeOperation(response: response)) { error in
+            XCTAssertEqual((error as NSError).code, MSIDErrorCode.internal.rawValue)
+            XCTAssertEqual((error as NSError).domain, MSIDErrorDomain)
+            XCTAssertEqual((error as NSError).userInfo["MSIDErrorDescriptionKey"] as? String, "Parent response of type MSIDSwitchBrowserResponse is required for creating MSIDSwitchBrowserResumeOperation")
+        }
+    }
 
     func testInit_withInValidResponse_shouldReturnNil() throws
     {