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, 8 insertions, 9 deletions

diff --git a/tests/object/blob/write.c b/tests/object/blob/write.c
index 9a18d7cd4..802467498 100644
--- a/tests/object/blob/write.c
+++ b/tests/object/blob/write.c
@@ -1,5 +1,4 @@
 #include "clar_libgit2.h"
-#include "buffer.h"
 #include "posix.h"
 #include "path.h"
 #include "futils.h"
@@ -38,32 +37,32 @@ void test_object_blob_write__can_create_a_blob_in_a_standard_repo_from_a_file_lo
 
 void test_object_blob_write__can_create_a_blob_in_a_standard_repo_from_a_absolute_filepath_pointing_outside_of_the_working_directory(void)
 {
-	git_buf full_path = GIT_BUF_INIT;
+	git_str full_path = GIT_STR_INIT;
 
 	repo = cl_git_sandbox_init(WORKDIR);
 
 	cl_must_pass(p_mkdir(ELSEWHERE, 0777));
 	cl_must_pass(git_path_prettify_dir(&full_path, ELSEWHERE, NULL));
-	cl_must_pass(git_buf_puts(&full_path, "test.txt"));
+	cl_must_pass(git_str_puts(&full_path, "test.txt"));
 
-	assert_blob_creation(ELSEWHERE "/test.txt", git_buf_cstr(&full_path), &git_blob_create_from_disk);
+	assert_blob_creation(ELSEWHERE "/test.txt", git_str_cstr(&full_path), &git_blob_create_from_disk);
 
-	git_buf_dispose(&full_path);
+	git_str_dispose(&full_path);
 	cl_must_pass(git_futils_rmdir_r(ELSEWHERE, NULL, GIT_RMDIR_REMOVE_FILES));
 }
 
 void test_object_blob_write__can_create_a_blob_in_a_bare_repo_from_a_absolute_filepath(void)
 {
-	git_buf full_path = GIT_BUF_INIT;
+	git_str full_path = GIT_STR_INIT;
 
 	repo = cl_git_sandbox_init(BARE_REPO);
 
 	cl_must_pass(p_mkdir(ELSEWHERE, 0777));
 	cl_must_pass(git_path_prettify_dir(&full_path, ELSEWHERE, NULL));
-	cl_must_pass(git_buf_puts(&full_path, "test.txt"));
+	cl_must_pass(git_str_puts(&full_path, "test.txt"));
 
-	assert_blob_creation(ELSEWHERE "/test.txt", git_buf_cstr(&full_path), &git_blob_create_from_disk);
+	assert_blob_creation(ELSEWHERE "/test.txt", git_str_cstr(&full_path), &git_blob_create_from_disk);
 
-	git_buf_dispose(&full_path);
+	git_str_dispose(&full_path);
 	cl_must_pass(git_futils_rmdir_r(ELSEWHERE, NULL, GIT_RMDIR_REMOVE_FILES));
 }