Pattern width is not applied for missing source information

[Nedra1998]

If the width is set in the format pattern for one of the source information fields (for example %10s), this width is only applied for messages which contain the source information. For example, this code

#include <spdlog/spdlog.h>

int main(int argc, char *argv[]) {
  spdlog::set_pattern("(%10s:%10#:%10!) %v");

  spdlog::info("Hello World");
  SPDLOG_INFO("Hello World");
}

will produce the output

$ ./a.out
(::) Hello World
(  main.cpp:         7:      main) Hello World

while I would expect it to produce output similar to this, to respect the alignment specified, even if the fields are not available.

$ ./a.out
(          :          :          ) Hello World
(  main.cpp:         7:      main) Hello World