From 75140682e74a07561f71bdb2be20b8168c602b0e Mon Sep 17 00:00:00 2001
From: "mergify[bot]" <37929162+mergify[bot]@users.noreply.github.com>
Date: Wed, 19 Apr 2023 11:24:43 -0400
Subject: [PATCH] Bugfix FXIOS-6206 [v112.2] Restore iOS version checks on js
 injection (#14011) (#14016)

* Restore iOS version checks on js injection

* Add a comment for future reference

* Fix swiftlint

(cherry picked from commit d28cd9d0560cfa98d3092e9f87c2bd48bac5e484)

Co-authored-by: OrlaM <omitchell@mozilla.com>
---
 Shared/Extensions/WKWebViewExtensions.swift | 62 ++++++++++++++++-----
 1 file changed, 49 insertions(+), 13 deletions(-)

diff --git a/Shared/Extensions/WKWebViewExtensions.swift b/Shared/Extensions/WKWebViewExtensions.swift
index b8868384c7ab..b47a7a9a4789 100644
--- a/Shared/Extensions/WKWebViewExtensions.swift
+++ b/Shared/Extensions/WKWebViewExtensions.swift
@@ -6,24 +6,40 @@ import Foundation
 import WebKit
 
 extension WKWebView {
-    /// This calls WebKit evaluateJavaScript function
+    /// This calls different WebKit evaluateJavaScript functions depending on iOS version
+    ///  - If iOS14 or higher, evaluates Javascript in a .defaultClient sandboxed content world
+    ///  - If below iOS14, evaluates Javascript without sandboxed environment
     /// - Parameters:
     ///     - javascript: String representing javascript to be evaluated
     public func evaluateJavascriptInDefaultContentWorld(_ javascript: String) {
-        self.evaluateJavaScript(javascript, in: nil, in: .defaultClient, completionHandler: { _ in })
+        // iOS 14.3 is required here because of a webkit bug in lower iOS versions with this API
+        if #available(iOS 14.3, *) {
+            self.evaluateJavaScript(javascript, in: nil, in: .defaultClient, completionHandler: { _ in })
+        } else {
+            self.evaluateJavaScript(javascript)
+        }
     }
 
-    /// This calls WebKit evaluateJavaScript function with a completion that passes a tuple with optional data or an optional error
+    /// This calls different WebKit evaluateJavaScript functions depending on iOS version with a completion that passes a tuple with optional data or an optional error
+    ///  - If iOS14 or higher, evaluates Javascript in a .defaultClient sandboxed content world
+    ///  - If below iOS14, evaluates Javascript without sandboxed environment
     /// - Parameters:
     ///     - javascript: String representing javascript to be evaluated
     ///     - completion: Tuple containing optional data and an optional error
     public func evaluateJavascriptInDefaultContentWorld(_ javascript: String, _ completion: @escaping (Any?, Error?) -> Void) {
-        self.evaluateJavaScript(javascript, in: nil, in: .defaultClient) { result in
-            switch result {
-            case .success(let value):
-                completion(value, nil)
-            case .failure(let error):
-                completion(nil, error)
+        // iOS 14.3 is required here because of a webkit bug in lower iOS versions with this API
+        if #available(iOS 14.3, *) {
+            self.evaluateJavaScript(javascript, in: nil, in: .defaultClient) { result in
+                switch result {
+                case .success(let value):
+                    completion(value, nil)
+                case .failure(let error):
+                    completion(nil, error)
+                }
+            }
+        } else {
+            self.evaluateJavaScript(javascript) { data, error  in
+                completion(data, error)
             }
         }
     }
@@ -31,20 +47,40 @@ extension WKWebView {
 
 extension WKUserContentController {
     public func addInDefaultContentWorld(scriptMessageHandler: WKScriptMessageHandler, name: String) {
-        add(scriptMessageHandler, contentWorld: .defaultClient, name: name)
+        // iOS 14.3 is required here because of a webkit bug in lower iOS versions with this API
+        if #available(iOS 14.3, *) {
+            add(scriptMessageHandler, contentWorld: .defaultClient, name: name)
+        } else {
+            add(scriptMessageHandler, name: name)
+        }
     }
 
     public func addInPageContentWorld(scriptMessageHandler: WKScriptMessageHandler, name: String) {
-        add(scriptMessageHandler, contentWorld: .page, name: name)
+        // iOS 14.3 is required here because of a webkit bug in lower iOS versions with this API
+        if #available(iOS 14.3, *) {
+            add(scriptMessageHandler, contentWorld: .page, name: name)
+        } else {
+            add(scriptMessageHandler, name: name)
+        }
     }
 }
 
 extension WKUserScript {
     public class func createInDefaultContentWorld(source: String, injectionTime: WKUserScriptInjectionTime, forMainFrameOnly: Bool) -> WKUserScript {
-        return WKUserScript(source: source, injectionTime: injectionTime, forMainFrameOnly: forMainFrameOnly, in: .defaultClient)
+        // iOS 14.3 is required here because of a webkit bug in lower iOS versions with this API
+        if #available(iOS 14.3, *) {
+            return WKUserScript(source: source, injectionTime: injectionTime, forMainFrameOnly: forMainFrameOnly, in: .defaultClient)
+        } else {
+            return WKUserScript(source: source, injectionTime: injectionTime, forMainFrameOnly: forMainFrameOnly)
+        }
     }
 
     public class func createInPageContentWorld(source: String, injectionTime: WKUserScriptInjectionTime, forMainFrameOnly: Bool) -> WKUserScript {
-        return WKUserScript(source: source, injectionTime: injectionTime, forMainFrameOnly: forMainFrameOnly, in: .page)
+        // iOS 14.3 is required here because of a webkit bug in lower iOS versions with this API
+        if #available(iOS 14.3, *) {
+            return WKUserScript(source: source, injectionTime: injectionTime, forMainFrameOnly: forMainFrameOnly, in: .page)
+        } else {
+            return WKUserScript(source: source, injectionTime: injectionTime, forMainFrameOnly: forMainFrameOnly)
+        }
     }
 }