friend constexpr blocking_kind tag_invoke()

in include/unifex/via.hpp [279:300]

• 22 lines of code
• 9 McCabe index (conditional complexity)

  friend constexpr blocking_kind tag_invoke(
      tag_t<blocking>,
      const sender& sender) {
    const auto predBlocking = blocking(sender.pred_);
    const auto succBlocking = blocking(sender.succ_);
    if (predBlocking == blocking_kind::never &&
        succBlocking == blocking_kind::never) {
      return blocking_kind::never;
    } else if (
        predBlocking == blocking_kind::always_inline &&
        succBlocking == blocking_kind::always_inline) {
      return blocking_kind::always_inline;
    } else if (
        (predBlocking == blocking_kind::always_inline ||
         predBlocking == blocking_kind::always) &&
        (succBlocking == blocking_kind::always_inline ||
         succBlocking == blocking_kind::always)) {
      return blocking_kind::always;
    } else {
      return blocking_kind::maybe;
    }
  }