diff --git a/docs/usage/api-reference.md b/docs/usage/api-reference.md index d110a3637..a1dcc79ff 100644 --- a/docs/usage/api-reference.md +++ b/docs/usage/api-reference.md @@ -22,6 +22,8 @@ Backward compatibility of the API is not guaranteed at this point. pyodide.console.repr_shorten pyodide.console.displayhook pyodide.webloop.WebLoop + pyodide.create_proxy + pyodide.create_once_callable ``` diff --git a/src/core/hiwire.c b/src/core/hiwire.c index 13bc1f4c2..90faac1b5 100644 --- a/src/core/hiwire.c +++ b/src/core/hiwire.c @@ -388,17 +388,37 @@ EM_JS_REF(JsRef, hiwire_dir, (JsRef idobj), { return Module.hiwire.new_value(result); }); +static JsRef +convert_va_args(va_list args) +{ + JsRef idargs = hiwire_array(); + while (true) { + JsRef idarg = va_arg(args, JsRef); + if (idarg == NULL) { + break; + } + hiwire_push_array(idargs, idarg); + } + va_end(args); + return idargs; +} + EM_JS_REF(JsRef, hiwire_call, (JsRef idfunc, JsRef idargs), { let jsfunc = Module.hiwire.get_value(idfunc); let jsargs = Module.hiwire.get_value(idargs); return Module.hiwire.new_value(jsfunc(... jsargs)); }); -EM_JS_REF(JsRef, hiwire_call_OneArg, (JsRef idfunc, JsRef idarg), { - let jsfunc = Module.hiwire.get_value(idfunc); - let jsarg = Module.hiwire.get_value(idarg); - return Module.hiwire.new_value(jsfunc(jsarg)); -}); +JsRef +hiwire_call_va(JsRef idobj, ...) +{ + va_list args; + va_start(args, idobj); + JsRef idargs = convert_va_args(args); + JsRef idresult = hiwire_call(idobj, idargs); + hiwire_decref(idargs); + return idresult; +} EM_JS_REF(JsRef, hiwire_call_bound, @@ -427,6 +447,17 @@ EM_JS_REF(JsRef, return Module.hiwire.new_value(jsobj[jsname](... jsargs)); }); +JsRef +hiwire_call_member_va(JsRef idobj, const char* ptrname, ...) +{ + va_list args; + va_start(args, ptrname); + JsRef idargs = convert_va_args(args); + JsRef idresult = hiwire_call_member(idobj, ptrname, idargs); + hiwire_decref(idargs); + return idresult; +} + EM_JS_REF(JsRef, hiwire_new, (JsRef idobj, JsRef idargs), { let jsobj = Module.hiwire.get_value(idobj); let jsargs = Module.hiwire.get_value(idargs); diff --git a/src/core/hiwire.h b/src/core/hiwire.h index f5ea87cd8..3dea9b25c 100644 --- a/src/core/hiwire.h +++ b/src/core/hiwire.h @@ -364,13 +364,19 @@ hiwire_dir(JsRef idobj); * * idargs is a hiwire Array containing the arguments. * - * Returns: New reference */ JsRef hiwire_call(JsRef idobj, JsRef idargs); +/** + * Call a function + * + * Arguments are specified as a NULL-terminated variable arguments list of + * JsRefs. + * + */ JsRef -hiwire_call_OneArg(JsRef idfunc, JsRef idarg); +hiwire_call_va(JsRef idobj, ...); JsRef hiwire_call_bound(JsRef idfunc, JsRef idthis, JsRef idargs); @@ -378,15 +384,26 @@ hiwire_call_bound(JsRef idfunc, JsRef idthis, JsRef idargs); /** * Call a member function. * - * ptrname is the member name, as a char * to null-terminated UTF8. + * ptrname is the member name, as a null-terminated UTF8. * * idargs is a hiwire Array containing the arguments. * - * Returns: New reference */ JsRef hiwire_call_member(JsRef idobj, const char* ptrname, JsRef idargs); +/** + * Call a member function. + * + * ptrname is the member name, as a null-terminated UTF8. + * + * Arguments are specified as a NULL-terminated variable arguments list of + * JsRefs. + * + */ +JsRef +hiwire_call_member_va(JsRef idobj, const char* ptrname, ...); + /** * Calls the constructor of a class object. * diff --git a/src/core/jsproxy.c b/src/core/jsproxy.c index 2602c2d30..48fb35304 100644 --- a/src/core/jsproxy.c +++ b/src/core/jsproxy.c @@ -34,6 +34,7 @@ #include "hiwire.h" #include "js2python.h" #include "jsproxy.h" +#include "pyproxy.h" #include "python2js.h" #include "structmember.h" @@ -625,13 +626,14 @@ JsProxy_Await(JsProxy* self, PyObject* _args) return NULL; } - // Main - PyObject* result = NULL; - PyObject* loop = NULL; PyObject* fut = NULL; PyObject* set_result = NULL; PyObject* set_exception = NULL; + JsRef promise_id = NULL; + JsRef promise_handles = NULL; + JsRef promise_result = NULL; + PyObject* result = NULL; loop = _PyObject_CallNoArg(asyncio_get_event_loop); FAIL_IF_NULL(loop); @@ -644,26 +646,123 @@ JsProxy_Await(JsProxy* self, PyObject* _args) set_exception = _PyObject_GetAttrId(fut, &PyId_set_exception); FAIL_IF_NULL(set_exception); - JsRef promise_id = hiwire_resolve_promise(self->js); - JsRef idargs = hiwire_array(); - JsRef idarg; - // TODO: does this leak set_result and set_exception? See #1006. - idarg = python2js(set_result); - hiwire_push_array(idargs, idarg); - hiwire_decref(idarg); - idarg = python2js(set_exception); - hiwire_push_array(idargs, idarg); - hiwire_decref(idarg); - hiwire_decref(hiwire_call_member(promise_id, "then", idargs)); - hiwire_decref(promise_id); - hiwire_decref(idargs); + promise_id = hiwire_resolve_promise(self->js); + FAIL_IF_NULL(promise_id); + promise_handles = create_promise_handles(set_result, set_exception); + FAIL_IF_NULL(promise_handles); + promise_result = hiwire_call_member(promise_id, "then", promise_handles); + FAIL_IF_NULL(promise_result); result = _PyObject_CallMethodId(fut, &PyId___await__, NULL); finally: Py_CLEAR(loop); + Py_CLEAR(fut); Py_CLEAR(set_result); Py_CLEAR(set_exception); - Py_DECREF(fut); + hiwire_CLEAR(promise_id); + hiwire_CLEAR(promise_handles); + hiwire_CLEAR(promise_result); + return result; +} + +/** + * Overload for `then` for JsProxies with a `then` method. Of course without + * this overload, the call would just fall through to the normal `then` + * function. The advantage of this overload is that it automatically releases + * the references to the onfulfilled and onrejected callbacks, which is quite + * hard to do otherwise. + */ +PyObject* +JsProxy_then(JsProxy* self, PyObject* args, PyObject* kwds) +{ + PyObject* onfulfilled = NULL; + PyObject* onrejected = NULL; + JsRef promise_handles = NULL; + JsRef result_promise = NULL; + PyObject* result = NULL; + + static char* kwlist[] = { "onfulfilled", "onrejected", 0 }; + if (!PyArg_ParseTupleAndKeywords( + args, kwds, "|OO:then", kwlist, &onfulfilled, &onrejected)) { + return NULL; + } + if (onfulfilled == Py_None) { + Py_CLEAR(onfulfilled); + } + if (onrejected == Py_None) { + Py_CLEAR(onrejected); + } + promise_handles = create_promise_handles(onfulfilled, onrejected); + FAIL_IF_NULL(promise_handles); + result_promise = hiwire_call_member(self->js, "then", promise_handles); + if (result_promise == NULL) { + Py_CLEAR(onfulfilled); + Py_CLEAR(onrejected); + FAIL(); + } + result = JsProxy_create(result_promise); + +finally: + hiwire_CLEAR(promise_handles); + hiwire_CLEAR(result_promise); + return result; +} + +/** + * Overload for `catch` for JsProxies with a `then` method. + */ +PyObject* +JsProxy_catch(JsProxy* self, PyObject* onrejected) +{ + JsRef promise_handles = NULL; + JsRef result_promise = NULL; + PyObject* result = NULL; + + // We have to use create_promise_handles so that the handler gets released + // even if the promise resolves successfully. + promise_handles = create_promise_handles(NULL, onrejected); + FAIL_IF_NULL(promise_handles); + result_promise = hiwire_call_member(self->js, "then", promise_handles); + if (result_promise == NULL) { + Py_DECREF(onrejected); + FAIL(); + } + result = JsProxy_create(result_promise); + +finally: + hiwire_CLEAR(promise_handles); + hiwire_CLEAR(result_promise); + return result; +} + +/** + * Overload for `finally` for JsProxies with a `then` method. This isn't + * strictly necessary since one could get the same effect by just calling + * create_once_callable on the argument, but it'd be bad to have `then` and + * `catch` handle freeing the handler automatically but require something extra + * to use `finally`. + */ +PyObject* +JsProxy_finally(JsProxy* self, PyObject* onfinally) +{ + JsRef proxy = NULL; + JsRef result_promise = NULL; + PyObject* result = NULL; + + // Finally method is called no matter what so we can use + // `create_once_callable`. + proxy = create_once_callable(onfinally); + FAIL_IF_NULL(proxy); + result_promise = hiwire_call_member_va(self->js, "finally", proxy, NULL); + if (result_promise == NULL) { + Py_DECREF(onfinally); + FAIL(); + } + result = JsProxy_create(result_promise); + +finally: + hiwire_CLEAR(proxy); + hiwire_CLEAR(result_promise); return result; } @@ -1068,7 +1167,7 @@ JsProxy_create_subtype(int flags) // Make sure these stack allocations are large enough to fit! PyType_Slot slots[20]; int cur_slot = 0; - PyMethodDef methods[5]; + PyMethodDef methods[10]; int cur_method = 0; PyMemberDef members[5]; int cur_member = 0; @@ -1141,6 +1240,35 @@ JsProxy_create_subtype(int flags) if (flags & IS_AWAITABLE) { slots[cur_slot++] = (PyType_Slot){ .slot = Py_am_await, .pfunc = (void*)JsProxy_Await }; + methods[cur_method++] = (PyMethodDef){ + "then", + (PyCFunction)JsProxy_then, + METH_VARARGS | METH_KEYWORDS, + PyDoc_STR( + "then(onfulfilled : Callable = None, onrejected : Callable = None)" + " -> JsProxy" + "\n\n" + "The promise.then api, wrapped to manage the lifetimes of the " + "arguments"), + }; + methods[cur_method++] = (PyMethodDef){ + "catch", + (PyCFunction)JsProxy_catch, + METH_O, + PyDoc_STR("catch(onrejected : Callable) -> JsProxy" + "\n\n" + "The promise.catch api, wrapped to manage the lifetime of the " + "argument."), + }; + methods[cur_method++] = (PyMethodDef){ + "finally_", + (PyCFunction)JsProxy_finally, + METH_O, + PyDoc_STR("finally_(onrejected : Callable) -> JsProxy" + "\n\n" + "The promise.finally api, wrapped to manage the lifetime of " + "the argument."), + }; } if (flags & IS_CALLABLE) { tp_flags |= _Py_TPFLAGS_HAVE_VECTORCALL; diff --git a/src/core/main.c b/src/core/main.c index 6b33cd247..729caa133 100644 --- a/src/core/main.c +++ b/src/core/main.c @@ -109,7 +109,7 @@ main(int argc, char** argv) TRY_INIT_WITH_CORE_MODULE(error_handling); TRY_INIT(js2python); TRY_INIT_WITH_CORE_MODULE(JsProxy); - TRY_INIT(pyproxy); + TRY_INIT_WITH_CORE_MODULE(pyproxy); TRY_INIT(keyboard_interrupt); PyObject* module_dict = PyImport_GetModuleDict(); // borrowed diff --git a/src/core/pyproxy.c b/src/core/pyproxy.c index 12ff69a35..13032645a 100644 --- a/src/core/pyproxy.c +++ b/src/core/pyproxy.c @@ -5,6 +5,7 @@ #include "hiwire.h" #include "js2python.h" +#include "jsproxy.h" #include "python2js.h" _Py_IDENTIFIER(result); @@ -501,7 +502,7 @@ FutureDoneCallback_call_resolve(FutureDoneCallback* self, PyObject* result) JsRef result_js = NULL; JsRef output = NULL; result_js = python2js(result); - output = hiwire_call_OneArg(self->resolve_handle, result_js); + output = hiwire_call_va(self->resolve_handle, result_js, NULL); success = true; finally: @@ -523,7 +524,7 @@ FutureDoneCallback_call_reject(FutureDoneCallback* self) // wrap_exception looks up the current exception and wraps it in a Js error. excval = wrap_exception(false); FAIL_IF_NULL(excval); - result = hiwire_call_OneArg(self->reject_handle, excval); + result = hiwire_call_va(self->reject_handle, excval, NULL); success = true; finally: @@ -741,6 +742,22 @@ EM_JS_NUM(int, pyproxy_init_js, (), { }, }; + Module.callPyObject = function(ptrobj, ...jsargs) { + let idargs = Module.hiwire.new_value(jsargs); + let idresult; + try { + idresult = __pyproxy_apply(ptrobj, idargs); + } catch(e){ + Module.fatal_error(e); + } finally { + Module.hiwire.decref(idargs); + } + if(idresult === 0){ + _pythonexc2js(); + } + return Module.hiwire.pop_value(idresult); + }; + // Now a lot of boilerplate to wrap the abstract Object protocol wrappers // above in Javascript functions. @@ -785,6 +802,12 @@ EM_JS_NUM(int, pyproxy_init_js, (), { Module.hiwire.decref(idresult); return result; } + apply(jsthis, jsargs) { + return Module.callPyObject(_getPtr(this), ...jsargs); + } + call(jsthis, ...jsargs){ + return Module.callPyObject(_getPtr(this), ...jsargs); + } }; // Controlled by HAS_LENGTH, appears for any object with __len__ or sq_length @@ -1107,20 +1130,7 @@ EM_JS_NUM(int, pyproxy_init_js, (), { return result; }, apply: function (jsobj, jsthis, jsargs) { - let ptrobj = _getPtr(jsobj); - let idargs = Module.hiwire.new_value(jsargs); - let idresult; - try { - idresult = __pyproxy_apply(ptrobj, idargs); - } catch(e){ - Module.fatal_error(e); - } finally { - Module.hiwire.decref(idargs); - } - if(idresult === 0){ - _pythonexc2js(); - } - return Module.hiwire.pop_value(idresult); + return jsobj.apply(jsthis, jsargs); }, }; @@ -1220,14 +1230,138 @@ EM_JS_NUM(int, pyproxy_init_js, (), { Module.wrapNamespace = function wrapNamespace(ns){ return new Proxy(ns, NamespaceProxyHandlers); }; - return 0; }); // clang-format on -int -pyproxy_init() +EM_JS_REF(JsRef, create_once_callable, (PyObject * obj), { + _Py_IncRef(obj); + let alreadyCalled = false; + function wrapper(... args) + { + if (alreadyCalled) { + throw new Error("OnceProxy can only be called once"); + } + alreadyCalled = true; + try { + return Module.callPyObject(obj, ... args); + } finally { + _Py_DecRef(obj); + } + } + wrapper.destroy = function() + { + if (alreadyCalled) { + throw new Error("OnceProxy has already been destroyed"); + } + alreadyCalled = true; + _Py_DecRef(obj); + }; + return Module.hiwire.new_value(wrapper); +}); + +static PyObject* +create_once_callable_py(PyObject* _mod, PyObject* obj) { + JsRef ref = create_once_callable(obj); + PyObject* result = JsProxy_create(ref); + hiwire_decref(ref); + return result; +} + +// clang-format off +EM_JS_REF(JsRef, create_promise_handles, ( + PyObject* handle_result, PyObject* handle_exception +), { + if (handle_result) { + _Py_IncRef(handle_result); + } + if (handle_exception) { + _Py_IncRef(handle_exception); + } + let used = false; + function checkUsed(){ + if (used) { + throw new Error("One of the promise handles has already been called."); + } + } + function destroy(){ + checkUsed(); + used = true; + if(handle_result){ + _Py_DecRef(handle_result); + } + if(handle_exception){ + _Py_DecRef(handle_exception) + } + } + function onFulfilled(res) { + checkUsed(); + try { + if(handle_result){ + return Module.callPyObject(handle_result, res); + } + } finally { + destroy(); + } + } + function onRejected(err) { + checkUsed(); + try { + if(handle_exception){ + return Module.callPyObject(handle_exception, err); + } + } finally { + destroy(); + } + } + onFulfilled.destroy = destroy; + onRejected.destroy = destroy; + return Module.hiwire.new_value( + [onFulfilled, onRejected] + ); +}) +// clang-format on + +static PyObject* +create_proxy(PyObject* _mod, PyObject* obj) +{ + JsRef ref = pyproxy_new(obj); + PyObject* result = JsProxy_create(ref); + hiwire_decref(ref); + return result; +} + +static PyMethodDef pyproxy_methods[] = { + { + "create_once_callable", + create_once_callable_py, + METH_O, + PyDoc_STR( + "create_once_callable(obj : Callable) -> JsProxy" + "\n\n" + "Wrap a Python callable in a Javascript function that can be called " + "once. After being called the proxy will decrement the reference count " + "of the Callable. The javascript function also has a `destroy` API that " + "can be used to release the proxy without calling it."), + }, + { + "create_proxy", + create_proxy, + METH_O, + PyDoc_STR("create_proxy(obj : Any) -> JsProxy" + "\n\n" + "Create a `JsProxy` of a `PyProxy`. This allows explicit control " + "over the lifetime of the `PyProxy` from Python: call the " + "`destroy` API when done."), + }, + { NULL } /* Sentinel */ +}; + +int +pyproxy_init(PyObject* core) +{ + PyModule_AddFunctions(core, pyproxy_methods); asyncio = PyImport_ImportModule("asyncio"); if (asyncio == NULL) { return -1; diff --git a/src/core/pyproxy.h b/src/core/pyproxy.h index e64cc3f7c..2d77eedb6 100644 --- a/src/core/pyproxy.h +++ b/src/core/pyproxy.h @@ -3,15 +3,35 @@ #define PY_SSIZE_T_CLEAN #include "Python.h" -/** Makes Python objects usable from Javascript. +/** + * Makes Python objects usable from Javascript. */ // This implements the Javascript Proxy handler interface as defined here: -// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Proxy +// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Proxy JsRef pyproxy_new(PyObject* obj); +/** + * Wrap a Python callable in a Javascript function that can be called once. + * After being called, the reference count of the python object is automatically + * decremented. The Proxy also has a "destroy" API that can decrement the + * reference count without calling the function. + */ +JsRef +create_once_callable(PyObject* obj); + +/** + * Wrap a pair of Python callables in a Javascript function that can be called + * once between the two of them. After being called, the reference counts of + * both python objects are automatically decremented. The wrappers also have a + * "destroy" API that can decrement the reference counts without calling the + * function. Intended for use with `promise.then`. + */ +JsRef +create_promise_handles(PyObject* onfulfilled, PyObject* onrejected); + int pyproxy_init(); diff --git a/src/pyodide-py/pyodide/__init__.py b/src/pyodide-py/pyodide/__init__.py index eda0bf3cb..2809c85ae 100644 --- a/src/pyodide-py/pyodide/__init__.py +++ b/src/pyodide-py/pyodide/__init__.py @@ -1,5 +1,5 @@ from ._base import open_url, eval_code, eval_code_async, find_imports, as_nested_list -from ._core import JsException # type: ignore +from ._core import JsException, create_once_callable, create_proxy # type: ignore from ._importhooks import JsFinder from .webloop import WebLoopPolicy import asyncio @@ -26,4 +26,6 @@ __all__ = [ "JsException", "register_js_module", "unregister_js_module", + "create_once_callable", + "create_proxy", ] diff --git a/src/pyodide-py/pyodide/_core.py b/src/pyodide-py/pyodide/_core.py index 13ba6f4af..a29fa87ab 100644 --- a/src/pyodide-py/pyodide/_core.py +++ b/src/pyodide-py/pyodide/_core.py @@ -1,7 +1,13 @@ import platform +from typing import Any, Callable if platform.system() == "Emscripten": - from _pyodide_core import JsProxy, JsException + from _pyodide_core import ( + JsProxy, + JsException, + create_proxy, + create_once_callable, + ) else: # Can add shims here if we are so inclined. class JsException(Exception): # type: ignore @@ -16,5 +22,23 @@ else: # Defined in jsproxy.c + # Defined in jsproxy.c -__all__ = ["JsProxy", "JsException"] + def create_once_callable(obj: Callable) -> JsProxy: + """Wrap a Python callable in a Javascript function that can be called + once. After being called the proxy will decrement the reference count + of the Callable. The javascript function also has a `destroy` API that + can be used to release the proxy without calling it. + """ + return obj + + def create_proxy(obj: Any) -> JsProxy: + """Create a `JsProxy` of a `PyProxy`. + + This allows explicit control over the lifetime of the `PyProxy` from + Python: call the `destroy` API when done. + """ + return obj + + +__all__ = ["JsProxy", "JsException", "create_proxy", "create_once_callable"] diff --git a/src/pyodide-py/pyodide/webloop.py b/src/pyodide-py/pyodide/webloop.py index 8788c60a6..822c4d36d 100644 --- a/src/pyodide-py/pyodide/webloop.py +++ b/src/pyodide-py/pyodide/webloop.py @@ -132,11 +132,12 @@ class WebLoop(asyncio.AbstractEventLoop): This uses `setTimeout(callback, delay)` """ from js import setTimeout + from . import create_once_callable if delay < 0: raise ValueError("Can't schedule in the past") h = asyncio.Handle(callback, args, self, context=context) - setTimeout(h._run, delay * 1000) + setTimeout(create_once_callable(h._run), delay * 1000) return h def call_at( diff --git a/src/tests/test_asyncio.py b/src/tests/test_asyncio.py index 4d51580b0..53d363d00 100644 --- a/src/tests/test_asyncio.py +++ b/src/tests/test_asyncio.py @@ -35,6 +35,122 @@ def test_await_jsproxy(selenium): ) +def test_then_jsproxy(selenium): + selenium.run( + """ + def prom(res, rej): + global resolve + global reject + resolve = res + reject = rej + + from js import Promise + result = None + err = None + finally_occurred = False + + def onfulfilled(value): + global result + result = value + + def onrejected(value): + global err + err = value + + def onfinally(): + global finally_occurred + finally_occurred = True + """ + ) + + selenium.run( + """ + p = Promise.new(prom) + p.then(onfulfilled, onrejected) + resolve(10) + """ + ) + time.sleep(0.01) + selenium.run( + """ + assert result == 10 + assert err is None + result = None + """ + ) + + selenium.run( + """ + p = Promise.new(prom) + p.then(onfulfilled, onrejected) + reject(10) + """ + ) + time.sleep(0.01) + selenium.run( + """ + assert result is None + assert err == 10 + err = None + """ + ) + + selenium.run( + """ + p = Promise.new(prom) + p.catch(onrejected) + resolve(10) + """ + ) + time.sleep(0.01) + selenium.run("assert err is None") + + selenium.run( + """ + p = Promise.new(prom) + p.catch(onrejected) + reject(10) + """ + ) + time.sleep(0.01) + selenium.run( + """ + assert err == 10 + err = None + """ + ) + + selenium.run( + """ + p = Promise.new(prom) + p.finally_(onfinally) + resolve(10) + """ + ) + time.sleep(0.01) + selenium.run( + """ + assert finally_occurred + finally_occurred = False + """ + ) + + selenium.run( + """ + p = Promise.new(prom) + p.finally_(onfinally) + reject(10) + """ + ) + time.sleep(0.01) + selenium.run( + """ + assert finally_occurred + finally_occurred = False + """ + ) + + def test_await_fetch(selenium): selenium.run( """ diff --git a/src/tests/test_pyodide.py b/src/tests/test_pyodide.py index d447ccb87..1a49c7c44 100644 --- a/src/tests/test_pyodide.py +++ b/src/tests/test_pyodide.py @@ -255,3 +255,87 @@ def test_run_python_last_exc(selenium): `); """ ) + + +def test_create_once_callable(selenium): + selenium.run_js( + """ + window.call7 = function call7(f){ + return f(7); + } + pyodide.runPython(` + from pyodide import create_once_callable, JsException + from js import call7; + from unittest import TestCase + raises = TestCase().assertRaisesRegex + class Square: + def __call__(self, x): + return x*x + + def __del__(self): + global destroyed + destroyed = True + + f = Square() + import sys + assert sys.getrefcount(f) == 2 + proxy = create_once_callable(f) + assert sys.getrefcount(f) == 3 + assert call7(proxy) == 49 + assert sys.getrefcount(f) == 2 + with raises(JsException, "can only be called once"): + call7(proxy) + destroyed = False + del f + assert destroyed == True + del proxy # causes a fatal error =( + `); + """ + ) + + +def test_create_proxy(selenium): + selenium.run_js( + """ + window.testAddListener = function(f){ + window.listener = f; + } + window.testCallListener = function(f){ + return window.listener(); + } + window.testRemoveListener = function(f){ + return window.listener === f; + } + pyodide.runPython(` + from pyodide import create_proxy + from js import testAddListener, testCallListener, testRemoveListener; + class Test: + def __call__(self): + return 7 + + def __del__(self): + global destroyed + destroyed = True + + f = Test() + import sys + assert sys.getrefcount(f) == 2 + proxy = create_proxy(f) + assert sys.getrefcount(f) == 3 + assert proxy() == 7 + testAddListener(proxy) + assert sys.getrefcount(f) == 3 + assert testCallListener() == 7 + assert sys.getrefcount(f) == 3 + assert testCallListener() == 7 + assert sys.getrefcount(f) == 3 + assert testRemoveListener(f) + assert sys.getrefcount(f) == 3 + proxy.destroy() + assert sys.getrefcount(f) == 2 + destroyed = False + del f + assert destroyed == True + `); + """ + )