Function array_reduce

src/PyListProxyHandler.cc:882–936

}

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

  if (!args.requireAtLeast(cx, "reduce", 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())) {
    JS_ReportErrorNumberASCII(cx, js::GetErrorMessage, nullptr, JSMSG_NOT_FUNCTION, "reduce: callback");
    return false;
  }

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

  JS::Rooted<JS::ValueArray<4>> jArgs(cx);
  JS::RootedValue *accumulator;

  Py_ssize_t len = PyList_GET_SIZE(self);

  if (args.length() > 1) {
    accumulator = new JS::RootedValue(cx, args[1].get());
  }
  else {
    if (len == 0) {
      JS_ReportErrorNumberASCII(cx, js::GetErrorMessage, nullptr, JSMSG_EMPTY_ARRAY_REDUCE);
      return false;
    }
    accumulator = new JS::RootedValue(cx, jsTypeFactory(cx, PyList_GetItem(self, 0)));
  }

  for (Py_ssize_t index = args.length() > 1 ? 0 : 1; index < len; index++) {
    jArgs[0].set(*accumulator);
    jArgs[1].set(jsTypeFactory(cx, PyList_GetItem(self, index)));
    jArgs[2].setInt32(index);
    jArgs[3].set(selfValue);

    if (!JS_CallFunctionValue(cx, nullptr, callBack, jArgs, accumulator)) {
      delete accumulator;
      return false;
    }
  }

  args.rval().set(accumulator->get());
  delete accumulator;
  return true;
}

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