Allow JS class to extend CLR type

sebastienros · Jan 11, 2022 · 91d119e · 91d119e
1 parent ceee6b2
commit 91d119e
Show file tree

Hide file tree

Showing 2 changed files with 20 additions and 4 deletions.
diff --git a/Jint.Tests/Runtime/InteropTests.cs b/Jint.Tests/Runtime/InteropTests.cs
@@ -787,6 +787,21 @@ public void CanUseDelegateAsFunction()
             ");
         }
 
+        [Fact]
+        public void JavaScriptClassCanExtendClrType()
+        {
+            var engine = new Engine();
+            engine.SetValue("TestClass", TypeReference.CreateTypeReference<TestClass>(engine));
+
+            engine.Execute("class MyExtendedType extends TestClass {}");
+            engine.Evaluate("let obj = new MyExtendedType();");
+
+            engine.Evaluate("obj.setString('Hello World!');");
+            var value = engine.Evaluate("obj.string");
+
+            Assert.Equal("Hello World!", value);
+        }
+
         private struct TestStruct
         {
             public int Value;

diff --git a/Jint/Native/Function/ClassDefinition.cs b/Jint/Native/Function/ClassDefinition.cs
@@ -6,6 +6,7 @@
 using Jint.Runtime;
 using Jint.Runtime.Descriptors;
 using Jint.Runtime.Environments;
+using Jint.Runtime.Interop;
 using Jint.Runtime.Interpreter;
 using Jint.Runtime.Interpreter.Expressions;
 
@@ -81,7 +82,7 @@ static MethodDefinition CreateConstructorMethodDefinition(string source)
                     protoParent = null;
                     constructorParent = engine.Realm.Intrinsics.Function.PrototypeObject;
                 }
-                else if (!superclass!.IsConstructor)
+                else if (!superclass.IsConstructor)
                 {
                     ExceptionHelper.ThrowTypeError(engine.Realm, "super class is not a constructor");
                 }
@@ -92,13 +93,13 @@ static MethodDefinition CreateConstructorMethodDefinition(string source)
                     {
                         protoParent = protoParentObject;
                     }
-                    else if (temp._type == InternalTypes.Null)
+                    else if (temp.IsNull() || superclass is TypeReference)
                     {
                         // OK
                     }
                     else
                     {
-                        ExceptionHelper.ThrowTypeError(engine.Realm);
+                        ExceptionHelper.ThrowTypeError(engine.Realm, "cannot resolve super class prototype chain");
                         return null!;
                     }
 
@@ -209,4 +210,4 @@ static MethodDefinition CreateConstructorMethodDefinition(string source)
             }
         }
     }
-}
+}