str: introduce `git_str` for internal, `git_buf` is externalethomson/gitstr

libgit2 has two distinct requirements that were previously solved by
`git_buf`.  We require:

1. A general purpose string class that provides a number of utility APIs
   for manipulating data (eg, concatenating, truncating, etc).
2. A structure that we can use to return strings to callers that they
   can take ownership of.

By using a single class (`git_buf`) for both of these purposes, we have
confused the API to the point that refactorings are difficult and
reasoning about correctness is also difficult.

Move the utility class `git_buf` to be called `git_str`: this represents
its general purpose, as an internal string buffer class.  The name also
is an homage to Junio Hamano ("gitstr").

The public API remains `git_buf`, and has a much smaller footprint.  It
is generally only used as an "out" param with strict requirements that
follow the documentation.  (Exceptions exist for some legacy APIs to
avoid breaking callers unnecessarily.)

Utility functions exist to convert a user-specified `git_buf` to a
`git_str` so that we can call internal functions, then converting it
back again.

1 files changed, 7 insertions, 8 deletions

diff --git a/tests/repo/setters.c b/tests/repo/setters.c
index 1fac627f6..2c33db0db 100644
--- a/tests/repo/setters.c
+++ b/tests/repo/setters.c
@@ -1,7 +1,6 @@
 #include "clar_libgit2.h"
 #include "git2/sys/repository.h"
 
-#include "buffer.h"
 #include "posix.h"
 #include "util.h"
 #include "path.h"
@@ -47,20 +46,20 @@ void test_repo_setters__setting_a_workdir_creates_a_gitlink(void)
 {
 	git_config *cfg;
 	git_buf buf = GIT_BUF_INIT;
-	git_buf content = GIT_BUF_INIT;
+	git_str content = GIT_STR_INIT;
 
 	cl_git_pass(git_repository_set_workdir(repo, "./new_workdir", true));
 
 	cl_assert(git_path_isfile("./new_workdir/.git"));
 
 	cl_git_pass(git_futils_readbuffer(&content, "./new_workdir/.git"));
-	cl_assert(git__prefixcmp(git_buf_cstr(&content), "gitdir: ") == 0);
-	cl_assert(git__suffixcmp(git_buf_cstr(&content), "testrepo.git/") == 0);
-	git_buf_dispose(&content);
+	cl_assert(git__prefixcmp(git_str_cstr(&content), "gitdir: ") == 0);
+	cl_assert(git__suffixcmp(git_str_cstr(&content), "testrepo.git/") == 0);
+	git_str_dispose(&content);
 
 	cl_git_pass(git_repository_config(&cfg, repo));
 	cl_git_pass(git_config_get_string_buf(&buf, cfg, "core.worktree"));
-	cl_assert(git__suffixcmp(git_buf_cstr(&buf), "new_workdir/") == 0);
+	cl_assert(git__suffixcmp(buf.ptr, "new_workdir/") == 0);
 
 	git_buf_dispose(&buf);
 	git_config_free(cfg);
@@ -81,7 +80,7 @@ void test_repo_setters__setting_a_new_index_on_a_repo_which_has_already_loaded_o
 
 	git_index_free(new_index);
 
-	/* 
+	/*
 	 * Ensure the cleanup method won't try to free the repo as it's already been taken care of
 	 */
 	repo = NULL;
@@ -102,7 +101,7 @@ void test_repo_setters__setting_a_new_odb_on_a_repo_which_already_loaded_one_pro
 
 	git_odb_free(new_odb);
 
-	/* 
+	/*
 	 * Ensure the cleanup method won't try to free the repo as it's already been taken care of
 	 */
 	repo = NULL;