Merge pull request #40 from cybozu/fix-memory-leak

Prevent memory leaks

Sources/WebUI/WebView+Extension.swift

@@ -20,7 +20,7 @@ extension WebView: View {
         @MainActor
         private func makeView() -> Remakeable<EnhancedWKWebView> {
             let webView = Remakeable<EnhancedWKWebView> {
-                let wrappedView = EnhancedWKWebView(frame: .zero, configuration: parent.configuration)
+                let wrappedView = EnhancedWKWebView(frame: .zero, configuration: parent.configuration ?? .init())
                 parent.applyModifiers(to: wrappedView)
                 return wrappedView
             }

Sources/WebUI/WebView.swift

@@ -13,12 +13,12 @@ import WebKit
 /// ```
 @available(iOS 16.4, macOS 13.3, *)
 public struct WebView {
-    let configuration: WKWebViewConfiguration
+    weak var configuration: WKWebViewConfiguration?
 
     private let initialRequest: URLRequest?
 
-    private var uiDelegate: (any WKUIDelegate)?
-    private var navigationDelegate: (any WKNavigationDelegate)?
+    private weak var uiDelegate: (any WKUIDelegate)?
+    private weak var navigationDelegate: (any WKNavigationDelegate)?
     private var isInspectable = false
     private var allowsBackForwardNavigationGestures = false
     private var allowsLinkPreview = true
@@ -30,7 +30,7 @@ public struct WebView {
     ///   - request: The initial request specifying the URL to load.
     ///   - configuration: The configuration for the new web view.
     @MainActor
-    public init(request: URLRequest? = nil, configuration: WKWebViewConfiguration = .init()) {
+    public init(request: URLRequest? = nil, configuration: WKWebViewConfiguration? = nil) {
         self.initialRequest = request
         self.configuration = configuration
     }

Tests/WebUITests/WebViewTests.swift

@@ -2,6 +2,14 @@
 import XCTest
 
 final class WebViewTests: XCTestCase {
+    @MainActor
+    func test_configuration_is_weakly_referenced() {
+        var configuration: WebViewConfigurationMock? = .init()
+        let sut = WebView(configuration: configuration)
+        configuration = nil
+        XCTAssertNil(sut.configuration)
+    }
+
     @MainActor
     func test_applyModifiers_uiDelegate() {
         let uiDelegateMock = UIDelegateMock()
@@ -11,6 +19,15 @@ final class WebViewTests: XCTestCase {
         XCTAssertTrue(uiDelegateMock === webViewMock.uiDelegate)
     }
 
+    @MainActor
+    func test_uiDelegate_is_weakly_referenced() {
+        var sut = WebView()
+        let actual = weaklyScope(UIDelegateMock()) {
+            sut = sut.uiDelegate($0)
+        }
+        XCTAssertNil(actual)
+    }
+
     @MainActor
     func test_applyModifiers_navigationDelegate() {
         let navigationDelegateMock = NavigationDelegateMock()
@@ -20,6 +37,15 @@ final class WebViewTests: XCTestCase {
         XCTAssertTrue(navigationDelegateMock === webViewMock.navigationDelegateProxy.delegate)
     }
 
+    @MainActor
+    func test_navigationDelegate_is_weakly_referenced() {
+        var sut = WebView()
+        let actual = weaklyScope(NavigationDelegateMock()) {
+            sut = sut.navigationDelegate($0)
+        }
+        XCTAssertNil(actual)
+    }
+
     @MainActor
     func test_applyModifiers_isInspectable() {
         let sut = WebView().allowsInspectable(true)

Tests/WebUITests/XCTestCase+Extension.swift

@@ -0,0 +1,15 @@
+import XCTest
+
+extension XCTestCase {
+    func weaklyScope<T: AnyObject>(
+        _ instance: @autoclosure () -> T,
+        perform action: (T) -> ()
+    ) -> T? {
+        weak var weakValue = {
+            let value = instance()
+            action(value)
+            return value
+        }()
+        return weakValue
+    }
+}