Document ability to disable template directory in git-init

[Boris Kolpackov <boris@xxxxxxxxxxxxxxxxx>]

Hello,

Looking at the git-init(1) man page, there doesn't appear to be a way
to disable copying the contents of the default template directory, other
than passing a path pointing to an empty directory.

However, if one passes an empty path, for example with the --template
option, then git does not complain and does not copy anything:

git init --template=

Looking at the code, this undocumented (AFAICS) behavior appears to
be there at least from git 2.1:


static void copy_templates(const char *template_dir)
{
	...

	if (!template_dir)
		template_dir = getenv(TEMPLATE_DIR_ENVIRONMENT);
	if (!template_dir)
		template_dir = init_db_template_dir;
	if (!template_dir)
		template_dir = system_path(DEFAULT_GIT_TEMPLATE_DIR);
	if (!template_dir[0])
		return;


For reference, the corresponding code in 2.50:


static void copy_templates(const char *option_template)
{
	const char *template_dir = get_template_dir(option_template);
	
	...

	if (!template_dir || !*template_dir)
		return;


I would like to suggest that we document this behavior so that it can
be relied upon. The motivation for omitting the default template are
repositories created by tools, such as package managers, for the sole
purpose of fetching some information from remotes. In this case all
the stuff copied from the template (such as hooks) is an unnecessary
waste of time and space.

Looking at the git-init(1) man page, the TEMPLATE DIRECTORY section
seems like the natural place to document this semantics. For example,
we could add the following sentence after the list of all the places
where the template directory can be specified:

"If the specified template directory is an empty path (for example,
--template=), then no template will be copied."

Let me know what you think.


Thanks,
Boris