Re: [PATCH v2 04/13] meson.build: set default help format to html on windows

> The build variable DEFAULT_HELP_FORMAT has an appropriate default
> ('man') set in the code, so there is no need to pass the -Define on
> the compiler command-line, unless the build requires a non-standard
> value.
> 
> In addition, on windows the make build overrides the default help
> format to 'html', rather than 'man', in the 'config.mak.uname' file.
> 
> In order to suppress the -Define on the C compiler command-line, only
> add the -Define to the 'libgit_c_args' variable when the requested
> value is not the standard 'man'. In order to override the default value
> on windows, add a 'platform' value to the 'default_help_format' combo
> option and set it as the default choice. When this option is set to
> 'platform', use the 'host_machine.system()' method call to determine the
> appropriate default value for the host system.
> 
> Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
> ---
>  meson.build       | 13 ++++++++++++-
>  meson_options.txt |  2 +-
>  2 files changed, 13 insertions(+), 2 deletions(-)
> 
> diff --git a/meson.build b/meson.build
> index efd0bd3319..8f8a258064 100644
> --- a/meson.build
> +++ b/meson.build
> @@ -694,7 +694,6 @@ endif
>  libgit_c_args = [
>    '-DBINDIR="' + get_option('bindir') + '"',
>    '-DDEFAULT_GIT_TEMPLATE_DIR="' + get_option('datadir') / 'git-core/templates' + '"',
> -  '-DDEFAULT_HELP_FORMAT="' + get_option('default_help_format') + '"',
>    '-DETC_GITATTRIBUTES="' + get_option('gitattributes') + '"',
>    '-DETC_GITCONFIG="' + get_option('gitconfig') + '"',
>    '-DFALLBACK_RUNTIME_PREFIX="' + get_option('prefix') + '"',
> @@ -717,6 +716,18 @@ if pager_opt != '' and pager_opt != 'less'
>    libgit_c_args += '-DDEFAULT_PAGER="' + pager_opt + '"'
>  endif
>  
> +help_format_opt = get_option('default_help_format')
> +if help_format_opt == 'platform'
> +  if host_machine.system() == 'windows'
> +    help_format_opt = 'html'
> +  else
> +    help_format_opt = 'man'
> +  endif
> +endif
> +if help_format_opt != 'man'
> +    libgit_c_args += '-DDEFAULT_HELP_FORMAT="' + help_format_opt + '"'
> +endif
> +