Introduce GIT_TEMPLATE_DIR

Instead of passing --template explicitely to init-db and clone, you can
just set the environment variable GIT_TEMPLATE_DIR.

Also make use of it in the tests, to make sure that the templates are
copied.
Signed-off-by: NJohannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

builtin-init-db.c

@@ -124,8 +124,11 @@ static void copy_templates(const char *git_dir, int len, const char *template_di
 	int template_len;
 	DIR *dir;
 
-	if (!template_dir)
-		template_dir = DEFAULT_GIT_TEMPLATE_DIR;
+	if (!template_dir) {
+		template_dir = getenv("GIT_TEMPLATE_DIR");
+		if (!template_dir)
+			template_dir = DEFAULT_GIT_TEMPLATE_DIR;
+	}
 	strcpy(template_path, template_dir);
 	template_len = strlen(template_path);
 	if (template_path[template_len-1] != '/') {

t/test-lib.sh

@@ -208,8 +208,9 @@ test_done () {
 # t/ subdirectory and are run in trash subdirectory.
 PATH=$(pwd)/..:$PATH
 GIT_EXEC_PATH=$(pwd)/..
+GIT_TEMPLATE_DIR=$(pwd)/../templates/blt
 HOME=$(pwd)/trash
-export PATH GIT_EXEC_PATH HOME
+export PATH GIT_EXEC_PATH GIT_TEMPLATE_DIR HOME
 
 GITPERLLIB=$(pwd)/../perl/blib/lib:$(pwd)/../perl/blib/arch/auto/Git
 export GITPERLLIB