Add basic Objective-C and JS bridging test (#124)

* Add basic Objective-C and JS bridging test

* Add sending a json representation to JS layer

* Move ObjC and JS bridge testing into it's own file

Author: maicki

Examples/Cocoa/Tests/Objective_CTests/ObjcJSBridgingTests.swift

@@ -0,0 +1,69 @@
+import Foundation
+import JavaScriptCore
+import XCTest
+
+@testable import Objective_C
+
+class ObjcJavaScriptCoreBridgingTestSuite: XCTestCase {
+    
+    static let _context: JSContext = JSContext()!
+    
+    override class func setUp() {
+        super.setUp();
+        injectJSFileIntoContext(fileName: "bundle", context: _context);
+    }
+    
+    // Inject a js file located in plank/Examples/Shared/
+    class func injectJSFileIntoContext(fileName: String, context: JSContext) {
+        let jsFileName = "\(fileName).js"
+        // The currentDirectoryPath is: plank/Examples/Cocoa/
+        let currentPath = FileManager.default.currentDirectoryPath
+        
+        let pathURL = URL(fileURLWithPath: currentPath)
+        let finalPathURL = pathURL.appendingPathComponent("..")
+            .appendingPathComponent("Shared")
+            .appendingPathComponent(jsFileName)
+        do {
+            let bundleContents = try String(contentsOf: finalPathURL, encoding: .utf8)
+            context.evaluateScript(bundleContents)
+        } catch {
+            print("Couldn't inject \(jsFileName) into JSContext")
+        }
+    }
+    
+    var context: JSContext {
+        return ObjcJavaScriptCoreBridgingTestSuite._context
+    }
+    
+    func testImageModelBridgingGetImage() {
+        // Expected modelc dictionary
+        let imageModelDictionary: JSONDict = [
+            "height": 300,
+            "width": 200,
+            "url": "https://picsum.photos/200/300"
+        ]
+        let expectedImage = Image(modelDictionary: imageModelDictionary);
+        let expectedImageDictionaryRepresentation = expectedImage.dictionaryObjectRepresentation()
+        
+        // Get image from js context
+        let getTestImageModelJSONFunction = context.objectForKeyedSubscript("getTestImageModelJSON")!
+        let jsImageModel = getTestImageModelJSONFunction.call(withArguments:[]).toObject() as! JSONDict
+        
+        XCTAssert(expectedImage.isEqual(to: Image(modelDictionary:jsImageModel)))
+        XCTAssert(jsImageModel == expectedImageDictionaryRepresentation)
+    }
+    
+    func testImageModelBridgingSendImage() {
+        // Expected model dictionary
+        let imageModelDictionary: JSONDict = [
+            "height": 300,
+            "width": 200,
+            "url": "https://picsum.photos/200/300"
+        ]
+        let imageModel = Image(modelDictionary: imageModelDictionary);
+        let imageModelDictionaryRepresentation = imageModel.dictionaryObjectRepresentation()
+        
+        let testImageModelJSON = context.objectForKeyedSubscript("sendTestImageModelJSON")!
+        XCTAssert(testImageModelJSON.call(withArguments:[imageModelDictionaryRepresentation]).toBool())
+    }
+}

Examples/Shared/bundle.js

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+'use strict';
+
+// Some helper to throw exceptions within JS
+
+function assert(condition, message) {
+  if (!condition) {
+    message = message || 'Assertion failed';
+    if (typeof Error !== 'undefined') {
+      throw new Error(message);
+    }
+    throw message; // Fallback
+  }
+}
+
+// Testing funtions
+
+function getTestImageModelJSON() {
+  return {
+    height: 300,
+    width: 200,
+    url: 'https://picsum.photos/200/300',
+  };
+}
+
+function sendTestImageModelJSON(passed) {
+  const expected = getTestImageModelJSON();
+
+  return (
+    expected.height === passed.height &&
+    expected.width === passed.width &&
+    expected.url === passed.url
+  );
+}