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, 5 insertions, 5 deletions

diff --git a/tests/refs/basic.c b/tests/refs/basic.c
index 9e4c22964..32742f9cc 100644
--- a/tests/refs/basic.c
+++ b/tests/refs/basic.c
@@ -49,7 +49,7 @@ void test_refs_basic__longpaths(void)
 	const char *base;
 	size_t base_len, extra_len;
 	ssize_t remain_len, i;
-	git_buf refname = GIT_BUF_INIT;
+	git_str refname = GIT_STR_INIT;
 	git_reference *one = NULL, *two = NULL;
 	git_oid id;
 
@@ -62,10 +62,10 @@ void test_refs_basic__longpaths(void)
 	remain_len = (ssize_t)MAX_PATH - (base_len + extra_len);
 	cl_assert(remain_len > 0);
 
-	cl_git_pass(git_buf_puts(&refname, "refs/heads/"));
+	cl_git_pass(git_str_puts(&refname, "refs/heads/"));
 
 	for (i = 0; i < remain_len; i++) {
-		cl_git_pass(git_buf_putc(&refname, 'a'));
+		cl_git_pass(git_str_putc(&refname, 'a'));
 	}
 
 	/*
@@ -75,11 +75,11 @@ void test_refs_basic__longpaths(void)
 	cl_git_pass(git_reference_create(&one, g_repo, refname.ptr, &id, 0, NULL));
 
 	/* Adding one more character gives us a path that is too long. */
-	cl_git_pass(git_buf_putc(&refname, 'z'));
+	cl_git_pass(git_str_putc(&refname, 'z'));
 	cl_git_fail(git_reference_create(&two, g_repo, refname.ptr, &id, 0, NULL));
 
 	git_reference_free(one);
 	git_reference_free(two);
-	git_buf_dispose(&refname);
+	git_str_dispose(&refname);
 #endif
 }