Re: git complains packed-refs is not a directory when used with GIT_DIR and GIT_WORK_TREE envvars.

[Duy Nguyen <pclouds@gmail.com>]

On Tue, Mar 27, 2018 at 07:09:36PM +0200, Duy Nguyen wrote:
> I would rather have something like ref_store_reinit() in the same
> spirit as the second call of set_git_dir() in setup_work_tree. It is
> hacky, but it works and keeps changes to minimal (so that it could be
> easily replaced later).

So in the name of hacky and dirty things, it would look something like
this. This passed your test case. The test suite is still running
(slow laptop) but I don't expect breakages there.

-- 8< --
diff --git a/refs.c b/refs.c
index 20ba82b434..c6116c4f7a 100644
--- a/refs.c
+++ b/refs.c
@@ -1660,6 +1660,16 @@ struct ref_store *get_main_ref_store(void)
 	return main_ref_store;
 }
 
+void make_main_ref_store_use_absolute_paths(void)
+{
+	files_force_absolute_paths(get_main_ref_store());
+}
+
+void make_main_ref_store_use_relative_paths(const char *cwd)
+{
+	files_make_relative_paths(get_main_ref_store(), cwd);
+}
+
 /*
  * Associate a ref store with a name. It is a fatal error to call this
  * function twice for the same name.
diff --git a/refs.h b/refs.h
index 01be5ae32f..532a4ad09d 100644
--- a/refs.h
+++ b/refs.h
@@ -759,6 +759,9 @@ int reflog_expire(const char *refname, const struct object_id *oid,
 int ref_storage_backend_exists(const char *name);
 
 struct ref_store *get_main_ref_store(void);
+void make_main_ref_store_use_absolute_paths(void);
+void make_main_ref_store_use_relative_paths(const char *cwd);
+
 /*
  * Return the ref_store instance for the specified submodule. For the
  * main repository, use submodule==NULL; such a call cannot fail. For
diff --git a/refs/files-backend.c b/refs/files-backend.c
index bec8e30e9e..629198826f 100644
--- a/refs/files-backend.c
+++ b/refs/files-backend.c
@@ -3092,6 +3092,32 @@ static int files_reflog_expire(struct ref_store *ref_store,
 	return -1;
 }
 
+void files_force_absolute_paths(struct ref_store *ref_store)
+{
+	struct files_ref_store *refs =
+		files_downcast(ref_store, REF_STORE_WRITE, "don't ask");
+
+	char *path = refs->gitdir;
+	refs->gitdir = absolute_pathdup(path);
+	free(path);
+
+	path = refs->gitcommondir;
+	refs->gitcommondir = absolute_pathdup(path);
+	free(path);
+}
+
+void files_make_relative_paths(struct ref_store *ref_store, const char *cwd)
+{
+	struct files_ref_store *refs =
+		files_downcast(ref_store, REF_STORE_WRITE, "don't ask");
+
+	const char *path = remove_leading_path(refs->gitdir, cwd);
+	refs->gitdir = absolute_pathdup(path);
+
+	path = remove_leading_path(refs->gitcommondir, cwd);
+	refs->gitcommondir = absolute_pathdup(path);
+}
+
 static int files_init_db(struct ref_store *ref_store, struct strbuf *err)
 {
 	struct files_ref_store *refs =
diff --git a/refs/refs-internal.h b/refs/refs-internal.h
index dd834314bd..827e97bcca 100644
--- a/refs/refs-internal.h
+++ b/refs/refs-internal.h
@@ -669,4 +669,7 @@ struct ref_store {
 void base_ref_store_init(struct ref_store *refs,
 			 const struct ref_storage_be *be);
 
+void files_force_absolute_paths(struct ref_store *refs);
+void files_make_relative_paths(struct ref_store *refs, const char *cwd);
+
 #endif /* REFS_REFS_INTERNAL_H */
diff --git a/setup.c b/setup.c
index 7287779642..a5f4396b4e 100644
--- a/setup.c
+++ b/setup.c
@@ -3,6 +3,7 @@
 #include "config.h"
 #include "dir.h"
 #include "string-list.h"
+#include "refs.h"
 
 static int inside_git_dir = -1;
 static int inside_work_tree = -1;
@@ -389,8 +390,10 @@ void setup_work_tree(void)
 
 	work_tree = get_git_work_tree();
 	git_dir = get_git_dir();
-	if (!is_absolute_path(git_dir))
+	if (!is_absolute_path(git_dir)) {
 		git_dir = real_path(get_git_dir());
+		make_main_ref_store_use_absolute_paths();
+	}
 	if (!work_tree || chdir(work_tree))
 		die(_("this operation must be run in a work tree"));
 
@@ -402,6 +405,7 @@ void setup_work_tree(void)
 		setenv(GIT_WORK_TREE_ENVIRONMENT, ".", 1);
 
 	set_git_dir(remove_leading_path(git_dir, work_tree));
+	make_main_ref_store_use_relative_paths(work_tree);
 	initialized = 1;
 }
 
-- 8< --