Function array_map

src/PyListProxyHandler.cc:743–808

}

static bool array_map(JSContext *cx, unsigned argc, JS::Value *vp) {
  JS::CallArgs args = JS::CallArgsFromVp(argc, vp);

  if (!args.requireAtLeast(cx, "map", 1)) {
    return false;
  }

  JS::RootedObject proxy(cx, JS::ToObject(cx, args.thisv()));
  if (!proxy) {
    return false;
  }
  PyObject *self = JS::GetMaybePtrFromReservedSlot<PyObject>(proxy, PyObjectSlot);

  JS::Value callbackfn = args[0].get();

  if (!callbackfn.isObject() || !JS::IsCallable(&callbackfn.toObject())) {
    // Decompiling the faulty arg is not accessible through the JSAPI so we do the best effort for the error message
    JS_ReportErrorNumberASCII(cx, js::GetErrorMessage, nullptr, JSMSG_NOT_FUNCTION, "map: callback");
    return false;
  }

  Py_ssize_t len = PyList_GET_SIZE(self);

  JSObject *retArray = JS::NewArrayObject(cx, len);
  JS::RootedObject rootedRetArray(cx, retArray);

  JS::RootedValue selfValue(cx, jsTypeFactory(cx, self));
  JS::RootedValue callBack(cx, callbackfn);

  JS::Rooted<JS::ValueArray<3>> jArgs(cx);
  JS::RootedValue rval(cx);

  JS::RootedObject rootedThisArg(cx);
  if (args.length() > 1) {
    JS::Value thisArg = args[1].get();
    if (!thisArg.isObjectOrNull()) {
      JS_ReportErrorNumberASCII(cx, js::GetErrorMessage, nullptr, JSMSG_NOT_OBJORNULL, "'this' argument");
      return false;
    }

    // TODO support null, currently gets TypeError
    rootedThisArg.set(thisArg.toObjectOrNull());
    // check if callback is a PyMethod, need to make a new method bound to thisArg
    if (!makeNewPyMethod(cx, &callBack, rootedThisArg)) {
      return false;
    }
  }
  else {
    rootedThisArg.set(nullptr);
  }

  for (Py_ssize_t index = 0; index < len; index++) {
    jArgs[0].set(jsTypeFactory(cx, PyList_GetItem(self, index)));
    jArgs[1].setInt32(index);
    jArgs[2].set(selfValue);

    if (!JS_CallFunctionValue(cx, rootedThisArg, callBack, jArgs, &rval)) {
      return false;