Re: [PATCH] Introduce the GIT_HOME environment variable

[Michael J Gruber <git@drmicha.warpmail.net>]

Miklos Vajna venit, vidit, dixit 19.12.2009 16:30:
> Honor $GIT_HOME that is favoured over $HOME, just like $GIT_EDITOR
> overrides $EDITOR.  That allows us to extend the notion more naturally
> in the future.  For example, when we start reading from
> $HOME/.gitconfig, if the GIT_HOME environment is set, we would instead
> read from $GIT_HOME/.gitconfig.
> 
> Signed-off-by: Miklos Vajna <vmiklos@frugalware.org>
> ---
> 
> On Fri, Dec 18, 2009 at 09:55:07PM -0800, Junio C Hamano <gitster@pobox.com> wrote:
>> A possible solution might be for us to honor $GIT_HOME that is favoured
>> over $HOME, just like $GIT_EDITOR overrides $EDITOR.  That allows us to
>> extend the notion more naturally in the future.  For example, when we
>> start reading from $HOME/.git-excludes, if the GIT_HOME environment is
>> set, we would instead read from $GIT_HOME/.git-excludes.  That would be a
>> much cleaner solution than Miklos's patch [*2*].
> 
> Something like this?
> 
> I've stolen most of the commit message from your mail. ;-)

Yes, but it makes less sense this way... Junio wrote "when we start
reading" because we don't do that yet. But we read ~/.gitconfig, of
course, so "when we start reading" sounds funny here.

> 
>  Documentation/config.txt |   14 ++++++++++----
>  builtin-config.c         |    8 ++++++--
>  config.c                 |    4 +++-
>  path.c                   |    4 +++-
>  t/t1300-repo-config.sh   |    7 +++++++
>  5 files changed, 29 insertions(+), 8 deletions(-)
> 
> diff --git a/Documentation/config.txt b/Documentation/config.txt
> index a1e36d7..09cbc71 100644
> --- a/Documentation/config.txt
> +++ b/Documentation/config.txt
> @@ -8,6 +8,10 @@ is used to store the configuration for that repository, and
>  fallback values for the `.git/config` file. The file `/etc/gitconfig`
>  can be used to store a system-wide default configuration.
>  
> +In case you want to store your per-user configuration in a directory
> +different to `$HOME`, you can use the `$GIT_HOME` environment variable

"different from"

> +which has preference.
> +
>  The configuration variables are used by both the git plumbing
>  and the porcelains. The variables are divided into sections, wherein
>  the fully qualified variable name of the variable itself is the last
> @@ -406,8 +410,9 @@ core.excludesfile::
>  	In addition to '.gitignore' (per-directory) and
>  	'.git/info/exclude', git looks into this file for patterns
>  	of files which are not meant to be tracked.  "{tilde}/" is expanded
> -	to the value of `$HOME` and "{tilde}user/" to the specified user's
> -	home directory.  See linkgit:gitignore[5].
> +	to the value of `$GIT_HOME` (or `$HOME` if `$GIT_HOME` is not
> +	set) and "{tilde}user/" to the specified user's home directory.  See
> +	linkgit:gitignore[5].
>  
>  core.editor::
>  	Commands such as `commit` and `tag` that lets you edit
> @@ -707,8 +712,9 @@ color.ui::
>  
>  commit.template::
>  	Specify a file to use as the template for new commit messages.
> -	"{tilde}/" is expanded to the value of `$HOME` and "{tilde}user/" to the
> -	specified user's home directory.
> +	"{tilde}/" is expanded to the value of `$GIT_HOME` (or `$HOME`
> +	if `$GIT_HOME` is not set) and "{tilde}user/" to the specified user's
> +	home directory.
>  
>  diff.autorefreshindex::
>  	When using 'git-diff' to compare with work tree
> diff --git a/builtin-config.c b/builtin-config.c
> index a2d656e..da9ebd4 100644
> --- a/builtin-config.c
> +++ b/builtin-config.c
> @@ -146,7 +146,9 @@ static int get_value(const char *key_, const char *regex_)
>  
>  	local = config_exclusive_filename;
>  	if (!local) {
> -		const char *home = getenv("HOME");
> +		const char *home = getenv("GIT_HOME");
> +		if (!home)
> +			home = getenv("HOME");
>  		local = repo_config = git_pathdup("config");
>  		if (git_config_global() && home)
>  			global = xstrdup(mkpath("%s/.gitconfig", home));
> @@ -326,7 +328,9 @@ int cmd_config(int argc, const char **argv, const char *unused_prefix)
>  	}
>  
>  	if (use_global_config) {
> -		char *home = getenv("HOME");
> +		char *home = getenv("GIT_HOME");
> +		if (!home)
> +			home = getenv("HOME");
>  		if (home) {
>  			char *user_config = xstrdup(mkpath("%s/.gitconfig", home));
>  			config_exclusive_filename = user_config;
> diff --git a/config.c b/config.c
> index 37385ce..7e2ccdb 100644
> --- a/config.c
> +++ b/config.c
> @@ -711,7 +711,9 @@ int git_config(config_fn_t fn, void *data)
>  		found += 1;
>  	}
>  
> -	home = getenv("HOME");
> +	home = getenv("GIT_HOME");
> +	if (!home)
> +		home = getenv("HOME");
>  	if (git_config_global() && home) {
>  		char *user_config = xstrdup(mkpath("%s/.gitconfig", home));
>  		if (!access(user_config, R_OK)) {
> diff --git a/path.c b/path.c
> index 2ec950b..b42a1b6 100644
> --- a/path.c
> +++ b/path.c
> @@ -236,7 +236,9 @@ char *expand_user_path(const char *path)
>  		const char *username = path + 1;
>  		size_t username_len = first_slash - username;
>  		if (username_len == 0) {
> -			const char *home = getenv("HOME");
> +			const char *home = getenv("GIT_HOME");
> +			if (!home)
> +				home = getenv("HOME");
>  			strbuf_add(&user_path, home, strlen(home));
>  		} else {
>  			struct passwd *pw = getpw_str(username, username_len);
> diff --git a/t/t1300-repo-config.sh b/t/t1300-repo-config.sh
> index 83b7294..d9818ab 100755
> --- a/t/t1300-repo-config.sh
> +++ b/t/t1300-repo-config.sh
> @@ -18,6 +18,13 @@ EOF
>  
>  test_expect_success 'initial' 'cmp .git/config expect'
>  
> +test_expect_success 'GIT_HOME' '
> +	GIT_HOME="`pwd`" &&
> +	export GIT_HOME &&
> +	git config --global core.penguin "little blue" &&
> +	cmp "$GIT_HOME"/.gitconfig expect
> +'
> +
>  git config Core.Movie BadPhysics
>  
>  cat > expect << EOF