setup: don't perform lazy initialization of repository state

Under some circumstances (bogus GIT_DIR value or the discovered gitdir
is '.git') 'setup_git_directory()' won't initialize key repository
state.  This leads to inconsistent state after running the setup code.
To account for this inconsistent state, lazy initialization is done once
a caller asks for the repository's gitdir or some other piece of
repository state.  This is confusing and can be error prone.

Instead let's tighten the expected outcome of 'setup_git_directory()'
and ensure that it initializes repository state in all cases that would
have been handled by lazy initialization.

This also lets us drop the requirement to have 'have_git_dir()' check if
the environment variable GIT_DIR was set as that will be handled by the
end of the setup code.

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/cache.h b/cache.h
index 96055c2..7c81749 100644
--- a/cache.h
+++ b/cache.h
@@ -462,6 +462,8 @@ static inline enum object_type object_type(unsigned int mode)
  */
 extern const char * const local_repo_env[];
 
+extern void setup_git_env(void);
+
 /*
  * Returns true iff we have a configured git repository (either via
  * setup_git_directory, or in the environment via $GIT_DIR).