LibJS+LibWeb: Add JS::Object::inherits(class_name)

To allow implementing the DOM class hierarchy in JS bindings, this
patch adds an inherits() function that can be used to ask an Object
if it inherits from a specific C++ class (by name).

The necessary overrides are baked into each Object subclass by the
new JS_OBJECT macro, which works similarly to C_OBJECT in LibCore.

Thanks to @Dexesttp for suggesting this approach. :^)

1 files changed, 2 insertions, 1 deletions

diff --git a/Libraries/LibJS/Runtime/Function.h b/Libraries/LibJS/Runtime/Function.h
index 9e254f4bf6..8e19472fcc 100644
--- a/Libraries/LibJS/Runtime/Function.h
+++ b/Libraries/LibJS/Runtime/Function.h
@@ -32,6 +32,8 @@
 namespace JS {
 
 class Function : public Object {
+    JS_OBJECT(Function, Object);
+
 public:
     virtual ~Function();
     virtual void initialize(Interpreter&, GlobalObject&) override { }
@@ -60,7 +62,6 @@ public:
 protected:
     explicit Function(Object& prototype);
     Function(Object& prototype, Value bound_this, Vector<Value> bound_arguments);
-    virtual const char* class_name() const override { return "Function"; }
 
 private:
     virtual bool is_function() const final { return true; }