Thousands separator is buggy (L specifier)

[rbrich]

L specifier with en_US locale gives wrong output in some cases:

#include <fmt/format.h>
#include <locale>

int main() {
  std::locale::global(std::locale("en_US.UTF-8"));
  fmt::print("    256  => {:>10L}\n", 256);
  fmt::print("   1000  => {:>10L}\n", 1000);
  fmt::print("  34000  => {:>10L}\n", 34000);   // =>   134,000
  fmt::print(" 123456  => {:>10L}\n", 123456);  // =>  ,123,456
  fmt::print("   -256  => {:>10L}\n", -256);    // =>      ,256
  fmt::print("  -1000  => {:>10L}\n", -1000);
  fmt::print(" -34000  => {:>10L}\n", -34000);  // =>  --34,000
  fmt::print("-123456  => {:>10L}\n", -123456); // => -,123,456
}

https://godbolt.org/z/4ax5Tr

Minimal reproducer (the width and alignment doesn't matter):

fmt::format(std::locale("en_US.UTF-8"), "{:L}", -256);

[vitaut]

Good catch, thanks. Some of these are already fixed in 7.0.3 and the issue with a sign is fixed in a5e7e7d.