absl::FlagsUsageConfig::contains_helppackage_flags

Returns true if flags defined in the filename should be reported with ‐‐helppackage flag. For example, if the file "path/to/my/code.cc" defines the flag "‐‐my_flag", and contains_helppackage_flags("path/to/my/code.cc") returns true, invoking the program with ‐‐helppackage will include information about ‐‐my_flag in the program output.