Improve exceptions when incorrectly instantiating interfaces

runtime/src/main/jni/MetadataNode.cpp

@@ -655,15 +655,10 @@ void MetadataNode::SetInnerTypes(Isolate* isolate, Local<Function>& ctorFunction
     if (treeNode->children != nullptr) {
         const auto& children = *treeNode->children;
 
-//		// prototype of outer class
-//		auto prototypeTemplate2 = ctorFunction->Get(V8StringConstants::GetPrototype(isolate)).As<Object>();
-
         for (auto curChild : children) {
             auto childNode = GetOrCreateInternal(curChild);
 
-            auto type = s_metadataReader.GetNodeType(curChild);
-            auto isStatic = s_metadataReader.IsNodeTypeStatic(type);
-
+            // The call to GetConstructorFunctionTemplate bootstraps the ctor function for the childNode
             auto innerTypeCtorFuncTemplate = childNode->GetConstructorFunctionTemplate(isolate, curChild);
             auto innerTypeCtorFunc = Local<Function>::New(isolate, *GetOrCreateInternal(curChild)->GetPersistentConstructorFunction(isolate));
             auto innerTypeName = ArgConverter::ConvertToV8String(isolate, curChild->name);
@@ -684,6 +679,8 @@ Local<FunctionTemplate> MetadataNode::GetConstructorFunctionTemplate(Isolate* is
     SET_PROFILER_FRAME();
     tns::instrumentation::Frame frame;
 
+    v8::HandleScope handleScope(isolate);
+
     //try get cached "ctorFuncTemplate"
     Local<FunctionTemplate> ctorFuncTemplate;
     auto cache = GetMetadataNodeCache(isolate);
@@ -817,12 +814,16 @@ void MetadataNode::ExtendedClassConstructorCallback(const v8::FunctionCallbackIn
     try {
         SET_PROFILER_FRAME();
 
-        assert(info.IsConstructCall());
+        if (!info.IsConstructCall()) {
+            throw NativeScriptException(string("Incorrectly calling a Java class as a method. Class must be created by invoking its constructor with the `new` keyword."));
+        }
 
         auto isolate = info.GetIsolate();
         auto thiz = info.This();
         auto extData = reinterpret_cast<ExtendedClassCallbackData*>(info.Data().As<External>()->Value());
 
+        v8::HandleScope handleScope(isolate);
+
         auto implementationObject = Local<Object>::New(isolate, *extData->implementationObject);
 
         const auto& extendName = extData->extendedName;
@@ -854,10 +855,16 @@ void MetadataNode::InterfaceConstructorCallback(const v8::FunctionCallbackInfo<v
     try {
         SET_PROFILER_FRAME();
 
+        if (!info.IsConstructCall()) {
+            throw NativeScriptException(string("Interface implementation must be invoked as a constructor with the `new` keyword."));
+        }
+
         auto isolate = info.GetIsolate();
         auto thiz = info.This();
         auto node = reinterpret_cast<MetadataNode*>(info.Data().As<External>()->Value());
 
+        v8::HandleScope handleScope(isolate);
+
         Local<Object> implementationObject;
         Local<String> v8ExtendName;
 

test-app/app/src/main/assets/app/tests/extendedClassesTests.js

@@ -73,4 +73,12 @@ describe("Tests extended classes ", function () {
 
 		expect(labelgetIMAGE_ID_PROP1).toBe(labelgetIMAGE_ID_PROP2);
 	});
+
+	it("should not crash with no exception when incorrectly calling extended class constructor", function () {
+	    let MyObj = java.lang.Object.extend({
+                        toString: () => { return "It's MyObj" }
+                    });
+
+        expect(() => { myObj() }).toThrow();
+	});
 });

test-app/app/src/main/assets/app/tests/testInterfaceImplementation.js

@@ -27,4 +27,8 @@ describe("Tests Java interfaces are implemented correctly", function () {
 
 		expect(callClose).toBe(true);
 	});
+
+	it("should not crash with no exception when calling interface incorrectly", function () {
+	    expect(() => { java.lang.Runnable({ run: () => { android.util.Log.d("Log", ""); } }) }).toThrow();
+	});
 });