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, 11 insertions, 13 deletions

diff --git a/tests/online/push_util.c b/tests/online/push_util.c
index b39f78114..94e310f3d 100644
--- a/tests/online/push_util.c
+++ b/tests/online/push_util.c
@@ -1,6 +1,4 @@
-
 #include "clar_libgit2.h"
-#include "buffer.h"
 #include "vector.h"
 #include "push_util.h"
 
@@ -57,7 +55,7 @@ int record_update_tips_cb(const char *refname, const git_oid *a, const git_oid *
 
 int create_deletion_refspecs(git_vector *out, const git_remote_head **heads, size_t heads_len)
 {
-	git_buf del_spec = GIT_BUF_INIT;
+	git_str del_spec = GIT_STR_INIT;
 	int valid;
 	size_t i;
 
@@ -70,9 +68,9 @@ int create_deletion_refspecs(git_vector *out, const git_remote_head **heads, siz
 
 		/* Create a refspec that deletes a branch in the remote */
 		if (strcmp(head->name, "refs/heads/master")) {
-			cl_git_pass(git_buf_putc(&del_spec, ':'));
-			cl_git_pass(git_buf_puts(&del_spec, head->name));
-			cl_git_pass(git_vector_insert(out, git_buf_detach(&del_spec)));
+			cl_git_pass(git_str_putc(&del_spec, ':'));
+			cl_git_pass(git_str_puts(&del_spec, head->name));
+			cl_git_pass(git_vector_insert(out, git_str_detach(&del_spec)));
 		}
 	}
 
@@ -88,7 +86,7 @@ int record_ref_cb(git_remote_head *head, void *payload)
 void verify_remote_refs(const git_remote_head *actual_refs[], size_t actual_refs_len, const expected_ref expected_refs[], size_t expected_refs_len)
 {
 	size_t i, j = 0;
-	git_buf msg = GIT_BUF_INIT;
+	git_str msg = GIT_STR_INIT;
 	const git_remote_head *actual;
 	char *oid_str;
 	bool master_present = false;
@@ -120,24 +118,24 @@ void verify_remote_refs(const git_remote_head *actual_refs[], size_t actual_refs
 	return;
 
 failed:
-	git_buf_puts(&msg, "Expected and actual refs differ:\nEXPECTED:\n");
+	git_str_puts(&msg, "Expected and actual refs differ:\nEXPECTED:\n");
 
 	for(i = 0; i < expected_refs_len; i++) {
 		oid_str = git_oid_tostr_s(expected_refs[i].oid);
-		cl_git_pass(git_buf_printf(&msg, "%s = %s\n", expected_refs[i].name, oid_str));
+		cl_git_pass(git_str_printf(&msg, "%s = %s\n", expected_refs[i].name, oid_str));
 	}
 
-	git_buf_puts(&msg, "\nACTUAL:\n");
+	git_str_puts(&msg, "\nACTUAL:\n");
 	for (i = 0; i < actual_refs_len; i++) {
 		actual = actual_refs[i];
 		if (master_present && !strcmp(actual->name, "refs/heads/master"))
 			continue;
 
 		oid_str = git_oid_tostr_s(&actual->oid);
-		cl_git_pass(git_buf_printf(&msg, "%s = %s\n", actual->name, oid_str));
+		cl_git_pass(git_str_printf(&msg, "%s = %s\n", actual->name, oid_str));
 	}
 
-	cl_fail(git_buf_cstr(&msg));
+	cl_fail(git_str_cstr(&msg));
 
-	git_buf_dispose(&msg);
+	git_str_dispose(&msg);
 }