     let lastSectionAppearanceMessageHandlerString = "lastSectionAppearanceHandler"
     let lastSectionAppearedMessageString = "lastSectionAppeared"
     let testValueMessageHandlerString = "testValueReceivedHandler"
+    let testValueKeyString = "value"
     var testValueReceivedExpectation: XCTestExpectation?
     var testValue: Any? = nil
     

    
    func evaluateJavaScript(js: String, then: (Any?) -> ()) {
        webVCConfiguredToEmitLastSectionAppearanceEvent.webView?.evaluateJavaScript("""
            window.webkit.messageHandlers.\(self.testValueMessageHandlerString).postMessage({"value": (() => {\(js)})()})
        """) { (result, error) in
            guard let error = error else {
                return

        case let messageString as String where messageString == lastSectionAppearedMessageString && message.name == lastSectionAppearanceMessageHandlerString:
            lastSectionAppearedMessageReceivedExpectation?.fulfill()
        case let messageDict as Dictionary<String, Any>:
            testValue = messageDict[testValueKeyString]
            testValueReceivedExpectation?.fulfill()
        default:
            return
