126121 2013-12-21 12:30:48 -0800 The JavaScriptCore API ignores dynamically created protocols 2013-12-30 16:44:22 -0800 1 1 1 Unclassified WebKit JavaScriptCore 528+ (Nightly build) Unspecified Unspecified NEW P2 Normal --- 1 markvjal webkit-unassigned barraclough brandon mhahnenberg sam oldest_to_newest 962264 0 219854 markvjal 2013-12-21 12:30:48 -0800 Created attachment 219854 Example of dynamically generated protocol ignored by JavaScriptCore I would like to use a dynamically generated protocol as my JSExport sub-protocol for interacting with JavaScriptCore. However JavaScriptCore ignores dynamically generated protocols. Attached is a snippet which shows the behaviour when the protocol is statically defined, and when it is dynamically defined. The "hello" method is only called when the protocol is statically defined. I have tracked down the issue to the private Objective-C runtime method _protocol_getMethodTypeEncoding() which returns null if the protocol method has been dynamically defined. Said method is extensively used in the ObjCCallbackFunction.mm file. A solution, if possible, would be to use the method_getTypeEncoding() method which correctly outputs the type encoding for both dynamically and statically generated protocol methods. 963411 1 brandon 2013-12-30 16:44:22 -0800 I've been investigating this bug as well, and it seems that the private _protocol_getMethodTypeEncoding method also emits type strings (e.g. 'v24@0:8@16' vs. 'v24@0:8@"JSValue"16') when the compiler's type information is available. This extended type information is used when invoking Objective-C code, specifically when parseObjCType calls typeOfClass in ObjcRuntimeExtras.h at L197. I made the appropriate changes to use method_getTypeEncoding instead like you suggested and most cases seem to work with the exception of methods that accept a JSValue as a parameter (such as a JS function). These end up getting passed an empty NSDictionary, so there's clearly some problems that occur when the argument type information isn't available to JSC. It may be possible to work around this by also providing protocols for these specific methods and then ignoring them when doing a dynamic export to avoid losing the type information. This is clearly less elegant though. 219854 2013-12-21 12:30:48 -0800 2013-12-21 12:30:48 -0800 Example of dynamically generated protocol ignored by JavaScriptCore JavaScriptCore-example.m application/octet-stream 1116 markvjal I2ltcG9ydCA8Rm91bmRhdGlvbi9Gb3VuZGF0aW9uLmg+CiNpbXBvcnQgPEphdmFTY3JpcHRDb3Jl L0phdmFTY3JpcHRDb3JlLmg+CiNpbXBvcnQgPG9iamMvcnVudGltZS5oPgoKLy9AcHJvdG9jb2wg TXlQcm90b2NvbCA8SlNFeHBvcnQ+Ci8vLSh2b2lkKWhlbGxvOwovL0BlbmQKCkBpbnRlcmZhY2Ug TXlDbGFzcyA6IE5TT2JqZWN0IC8vPE15UHJvdG9jb2w+Ci0odm9pZCloZWxsbzsKQGVuZAoKQGlt cGxlbWVudGF0aW9uIE15Q2xhc3MgOiBOU09iamVjdAotKHZvaWQpaGVsbG8KewogIE5TTG9nKEAi SGVsbG8hIik7Cn0KQGVuZAoKaW50IG1haW4oaW50IGFyZ2MsIGNoYXIgKmFyZ3ZbXSkgewogIEBh dXRvcmVsZWFzZXBvb2wgewogICAgQHByb3RvY29sKEpTRXhwb3J0KTsgLy8gU3R1YiBuZWVkZWQg dG8gbG9jYXRlIHRoZSBwcm90b2NvbCBhdCBydW50aW1lLgogICAgCiAgICBQcm90b2NvbCAqcHJv dCA9IG9iamNfYWxsb2NhdGVQcm90b2NvbCgiTXlQcm90b2NvbCIpOwogICAgcHJvdG9jb2xfYWRk UHJvdG9jb2wocHJvdCwgb2JqY19nZXRQcm90b2NvbCgiSlNDb250ZXh0IikpOwogICAgCiAgICAK ICAgIE1ldGhvZCBtID0gY2xhc3NfZ2V0SW5zdGFuY2VNZXRob2QoTlNDbGFzc0Zyb21TdHJpbmco QCJNeUNsYXNzIiksIE5TU2VsZWN0b3JGcm9tU3RyaW5nKEAiaGVsbG8iKSk7CiAgICBjb25zdCBj aGFyICp0eXBlcyA9IG1ldGhvZF9nZXRUeXBlRW5jb2RpbmcobSk7CiAgICAKICAgIHByb3RvY29s X2FkZE1ldGhvZERlc2NyaXB0aW9uKHByb3QsIE5TU2VsZWN0b3JGcm9tU3RyaW5nKEAiaGVsbG8i KSwgdHlwZXMsIHRydWUsIHRydWUpOwogICAgCiAgICBvYmpjX3JlZ2lzdGVyUHJvdG9jb2wocHJv dCk7CiAgICBjbGFzc19hZGRQcm90b2NvbChOU0NsYXNzRnJvbVN0cmluZyhAIk15Q2xhc3MiKSwg cHJvdCk7CiAgICAKICAgIAogICAgSlNDb250ZXh0ICpjb250ZXh0ID0gW1tKU0NvbnRleHQgYWxs b2NdIGluaXRdOwogICAgTXlDbGFzcyAqbXljbGFzcyA9IFtbTXlDbGFzcyBhbGxvY10gaW5pdF07 CiAgICBjb250ZXh0W0AiTXljbGFzcyJdID0gbXljbGFzczsKICAgIFtjb250ZXh0IGV2YWx1YXRl U2NyaXB0OkAiTXljbGFzcy5oZWxsbygpIl07CiAgfQp9