test(network-details): Add integration tests for completion handler swizzling

Verify that the swizzled dataTaskWithRequest:completionHandler:
and dataTaskWithURL:completionHandler: actually fire and populate
network details on breadcrumbs using real HTTP requests to
postman-echo.com.

Author: 43jay

Tests/SentryTests/Integrations/Performance/Network/SentryNetworkDetailSwizzlingTests.swift

@@ -0,0 +1,148 @@
+#if os(iOS) || os(tvOS)
+
+@_spi(Private) @testable import Sentry
+@_spi(Private) import SentryTestUtils
+import XCTest
+
+/// Integration tests that verify the completion-handler swizzling for replay's
+/// network detail capture actually works end-to-end.
+///
+/// Unlike the unit tests in SentryNetworkTrackerTests (which call tracker
+/// methods directly), these tests start the SDK, make real HTTP requests,
+/// and assert that the swizzled completion handler fires and populates
+/// network details on the resulting breadcrumb.
+///
+/// Uses postman-echo.com so no local test server is required.
+class SentryNetworkDetailSwizzlingTests: XCTestCase {
+
+    private let echoURL = URL(string: "https://postman-echo.com/get")!
+
+    override func setUp() {
+        super.setUp()
+
+        let options = Options()
+        options.dsn = TestConstants.dsnAsString(username: "SentryNetworkDetailSwizzlingTests")
+        options.tracesSampleRate = 1.0
+        options.enableNetworkBreadcrumbs = true
+        options.sessionReplay.networkDetailAllowUrls = ["postman-echo.com"]
+        options.sessionReplay.networkCaptureBodies = true
+        SentrySDK.start(options: options)
+    }
+
+    override func tearDown() {
+        super.tearDown()
+        clearTestState()
+    }
+
+    // MARK: - Tests
+
+    /// Verifies the swizzle of `-[NSURLSession dataTaskWithRequest:completionHandler:]`
+    /// captures response details into the breadcrumb.
+    func testDataTaskWithRequest_completionHandler_capturesNetworkDetails() throws {
+        let transaction = SentrySDK.startTransaction(
+            name: "Test", operation: "test", bindToScope: true
+        )
+
+        let expect = expectation(description: "Request completed")
+        expect.assertForOverFulfill = false
+
+        let session = URLSession(configuration: .default)
+        let request = URLRequest(url: echoURL)
+
+        var receivedData: Data?
+        var receivedResponse: URLResponse?
+        var receivedError: Error?
+
+        let task = session.dataTask(with: request) { data, response, error in
+            receivedData = data
+            receivedResponse = response
+            receivedError = error
+            expect.fulfill()
+        }
+        defer { task.cancel() }
+
+        task.resume()
+        wait(for: [expect], timeout: 5)
+
+        transaction.finish()
+
+        // Original completion handler received valid data
+        XCTAssertNil(receivedError, "Request should succeed")
+        XCTAssertNotNil(receivedData, "Should receive response data")
+        let httpResponse = try XCTUnwrap(receivedResponse as? HTTPURLResponse)
+        XCTAssertEqual(httpResponse.statusCode, 200)
+
+        // Network details were captured via the swizzled completion handler
+        let breadcrumb = try lastHTTPBreadcrumb(for: echoURL)
+        let details = try XCTUnwrap(
+            breadcrumb.data?[SentryReplayNetworkDetails.replayNetworkDetailsKey] as? SentryReplayNetworkDetails,
+            "Swizzled completion handler should have populated network details on the breadcrumb"
+        )
+        let serialized = details.serialize()
+        XCTAssertEqual(serialized["statusCode"] as? Int, 200)
+        XCTAssertNotNil(serialized["response"], "Response details should be captured")
+    }
+
+    /// Verifies the swizzle of `-[NSURLSession dataTaskWithURL:completionHandler:]`
+    /// captures response details into the breadcrumb.
+    func testDataTaskWithURL_completionHandler_capturesNetworkDetails() throws {
+        let transaction = SentrySDK.startTransaction(
+            name: "Test", operation: "test", bindToScope: true
+        )
+
+        let expect = expectation(description: "Request completed")
+        expect.assertForOverFulfill = false
+
+        let session = URLSession(configuration: .default)
+
+        var receivedData: Data?
+        var receivedResponse: URLResponse?
+        var receivedError: Error?
+
+        let task = session.dataTask(with: echoURL) { data, response, error in
+            receivedData = data
+            receivedResponse = response
+            receivedError = error
+            expect.fulfill()
+        }
+        defer { task.cancel() }
+
+        task.resume()
+        wait(for: [expect], timeout: 5)
+
+        transaction.finish()
+
+        // Original completion handler received valid data
+        XCTAssertNil(receivedError, "Request should succeed")
+        XCTAssertNotNil(receivedData, "Should receive response data")
+        let httpResponse = try XCTUnwrap(receivedResponse as? HTTPURLResponse)
+        XCTAssertEqual(httpResponse.statusCode, 200)
+
+        // Network details were captured via the swizzled completion handler
+        let breadcrumb = try lastHTTPBreadcrumb(for: echoURL)
+        let details = try XCTUnwrap(
+            breadcrumb.data?[SentryReplayNetworkDetails.replayNetworkDetailsKey] as? SentryReplayNetworkDetails,
+            "Swizzled completion handler should have populated network details on the breadcrumb"
+        )
+        let serialized = details.serialize()
+        XCTAssertEqual(serialized["statusCode"] as? Int, 200)
+        XCTAssertNotNil(serialized["response"], "Response details should be captured")
+    }
+
+    // MARK: - Helpers
+
+    /// Finds the most recent HTTP breadcrumb whose URL matches the given URL.
+    private func lastHTTPBreadcrumb(for url: URL) throws -> Breadcrumb {
+        let scope = SentrySDKInternal.currentHub().scope
+        let breadcrumbs = try XCTUnwrap(
+            Dynamic(scope).breadcrumbArray as [Breadcrumb]?,
+            "Scope should contain breadcrumbs"
+        )
+        let matching = breadcrumbs.filter {
+            $0.category == "http" && ($0.data?["url"] as? String)?.contains(url.host ?? "") == true
+        }
+        return try XCTUnwrap(matching.last, "Should find an HTTP breadcrumb for \(url)")
+    }
+}
+
+#endif // os(iOS) || os(tvOS)