Thank you for your help. I mostly understand what you're saying, but I'm not quite clear on what I'm doing that's making holder != this. Are there any common/semi-common things you can do while wrapping a c++ object in a JS Object's internalfield that causes this to happen?
When I say new MyType(), that calls into a FunctionTemplate that takes info.This() and puts a C++ object in its internal field. The "new MyType()" FunctionTemplate can have a bunch of stuff on it's Instance/Prototype templates including accessors, data members, etc, though I thought I filtered most of that out in my test cases. Is anything I said or maybe something I'm probably doing and didn't say going to cause the holder != this? Thank you so much. --Zac On Monday, October 31, 2016 at 1:39:29 AM UTC-7, Toon Verwaest wrote: > > It just follows JS property access semantics. And that's complicated. > > If you're trying to set a property, but it doesn't exist on the receiver, > we need check whether the property exists on the prototype chain. If it > does and has a setter, we need to call the setter. If it does and is > read-only, we need to throw. If it exists and isn't either of those, that > would mask a property up the prototype chain. Hence if we see an > interceptor that's not on the receiver, we need to check whether it has the > property. If it does, that would mask a non-writable/settable property > further up the prototype chain. > > So we basically get the attributes to see whether it exists and whether > it's writable. That can either be returned through the query callback, or > through the getter. > > Now for your specific problem; it seems like your simple example must > mismatch the actual code you're having. If you don't see your setter being > called at all, that just means that you put the setter on Point.prototype, > not on instances of Point. Setters for "native data properties"; which > includes interceptors; are only invoked on the receiver directly. Only real > JS accessors are called through the prototype chain. This again follows the > spec. > > On Mon, Oct 31, 2016 at 2:10 AM Zac Hansen <xax...@gmail.com <javascript:>> > wrote: > >> Stack traces for the working and non-working versions: >> >> https://gist.github.com/xaxxon/5eabcc079a3103abd0f7b3239b2cf3b2 >> >> >> my v8 source is at commit: >> >> a05f85a3db33860f7f9651d904fd4193ee757848 >> >> On Saturday, October 29, 2016 at 3:33:14 AM UTC-7, Zac Hansen wrote: >> >>> I run the following javascript: >>> >>> var p = new Point(); p.foo = 5; >>> >>> where Point creates an object from an ObjectTemplate that has >>> had SetHandler called on it. However, this calls my getter callback. >>> Everything I've tried from javascript calls my getter callback. >>> >>> object_template->SetHandler(v8::NamedPropertyHandlerConfiguration( >>> // Getter >>> [](v8::Local<v8::Name> property_name, >>> v8::PropertyCallbackInfo<v8::Value> const & info){ >>> printf("IN GETTER CALLBACK111 %s\n", >>> *v8::String::Utf8Value(property_name)); >>> }, >>> // setter >>> [](v8::Local<v8::Name> property_name, >>> v8::Local<v8::Value> new_property_value, >>> v8::PropertyCallbackInfo<v8::Value> const & info){ >>> printf("IN SETTER CALLBACK222 %s\n", >>> *v8::String::Utf8Value(property_name)); >>> }, >>> nullptr, // query >>> nullptr, // deleter >>> nullptr, // enumerator >>> v8::External::New(this->isolate, (void *)data), >>> v8::PropertyHandlerFlags::kNonMasking)); // <== >>> Tried with and without this >>> }; >>> >>> >>> and prints out: IN GETTER CALLBACK111 foo >>> >>> I originally tried with the older API for string-only property names and >>> had the same results. >>> >>> #define V8_MAJOR_VERSION 5 >>> #define V8_MINOR_VERSION 6 >>> #define V8_BUILD_NUMBER 0 >>> #define V8_PATCH_LEVEL 0 >>> >>> on os x 10.11 clang 3.9 >>> >> -- >> -- >> v8-users mailing list >> v8-u...@googlegroups.com <javascript:> >> http://groups.google.com/group/v8-users >> --- >> You received this message because you are subscribed to the Google Groups >> "v8-users" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to v8-users+u...@googlegroups.com <javascript:>. >> For more options, visit https://groups.google.com/d/optout. >> > -- -- v8-users mailing list v8-users@googlegroups.com http://groups.google.com/group/v8-users --- You received this message because you are subscribed to the Google Groups "v8-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to v8-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
