remote: deprecate resolve_url callback

Using a callback to set a resolve_url is not particularly idiomatic.
Deprecate it in favor of the `set_instance_url` and
`set_instance_pushurl` functions which can now be called from the
`git_remote_ready_cb` callback.

include/git2/remote.h

@@ -499,6 +499,7 @@ typedef int GIT_CALLBACK(git_push_negotiation)(const git_push_update **updates,
  */
 typedef int GIT_CALLBACK(git_push_update_reference_cb)(const char *refname, const char *status, void *data);
 
+#ifndef GIT_DEPRECATE_HARD
 /**
  * Callback to resolve URLs before connecting to remote
  *
@@ -510,8 +511,10 @@ typedef int GIT_CALLBACK(git_push_update_reference_cb)(const char *refname, cons
  * @param direction GIT_DIRECTION_FETCH or GIT_DIRECTION_PUSH
  * @param payload Payload provided by the caller
  * @return 0 on success, GIT_PASSTHROUGH or an error
+ * @deprecated Use `git_remote_set_instance_url`
  */
 typedef int GIT_CALLBACK(git_url_resolve_cb)(git_buf *url_resolved, const char *url, int direction, void *payload);
+#endif
 
 /**
  * Callback invoked immediately before we attempt to connect to the
@@ -620,11 +623,18 @@ struct git_remote_callbacks {
 	 */
 	void *payload;
 
+#ifdef GIT_DEPRECATE_HARD
+	void *reserved;
+#else
 	/**
 	 * Resolve URL before connecting to remote.
 	 * The returned URL will be used to connect to the remote instead.
+	 *
+	 * This callback is deprecated; users should use
+	 * git_remote_ready_cb and configure the instance URL instead.
 	 */
 	git_url_resolve_cb resolve_url;
+#endif
 };
 
 #define GIT_REMOTE_CALLBACKS_VERSION 1

src/remote.c

@@ -682,8 +682,16 @@ int git_remote_set_pushurl(git_repository *repo, const char *remote, const char*
 	return set_url(repo, remote, CONFIG_PUSHURL_FMT, url);
 }
 
-static int resolve_url(git_buf *resolved_url, const char *url, int direction, const git_remote_callbacks *callbacks)
-{
+static int resolve_url(
+	git_buf *resolved_url,
+	const char *url,
+	int direction,
+	const git_remote_callbacks *callbacks)
+{
+#ifdef GIT_DEPRECATE_HARD
+	GIT_UNUSED(direction);
+	GIT_UNUSED(callbacks);
+#else
 	int status, error;
 
 	if (callbacks && callbacks->resolve_url) {
@@ -698,11 +706,16 @@ static int resolve_url(git_buf *resolved_url, const char *url, int direction, co
 			return status;
 		}
 	}
+#endif
 
 	return git_buf_sets(resolved_url, url);
 }
 
-int git_remote__urlfordirection(git_buf *url_out, struct git_remote *remote, int direction, const git_remote_callbacks *callbacks)
+int git_remote__urlfordirection(
+	git_buf *url_out,
+	struct git_remote *remote,
+	int direction,
+	const git_remote_callbacks *callbacks)
 {
 	const char *url = NULL;
 

tests/network/remote/remotes.c

@@ -98,6 +98,7 @@ void test_network_remote_remotes__remote_ready(void)
 	git_buf_dispose(&url);
 }
 
+#ifndef GIT_DEPRECATE_HARD
 static int urlresolve_callback(git_buf *url_resolved, const char *url, int direction, void *payload)
 {
 	cl_assert(strcmp(url, "git://github.com/libgit2/libgit2") == 0);
@@ -111,9 +112,11 @@ static int urlresolve_callback(git_buf *url_resolved, const char *url, int direc
 
 	return GIT_OK;
 }
+#endif
 
 void test_network_remote_remotes__urlresolve(void)
 {
+#ifndef GIT_DEPRECATE_HARD
 	git_buf url = GIT_BUF_INIT;
 
 	git_remote_callbacks callbacks = GIT_REMOTE_CALLBACKS_INIT;
@@ -131,8 +134,10 @@ void test_network_remote_remotes__urlresolve(void)
 	cl_assert_equal_s(url.ptr, "pushresolve");
 
 	git_buf_dispose(&url);
+#endif
 }
 
+#ifndef GIT_DEPRECATE_HARD
 static int urlresolve_passthrough_callback(git_buf *url_resolved, const char *url, int direction, void *payload)
 {
 	GIT_UNUSED(url_resolved);
@@ -141,9 +146,11 @@ static int urlresolve_passthrough_callback(git_buf *url_resolved, const char *ur
 	GIT_UNUSED(payload);
 	return GIT_PASSTHROUGH;
 }
+#endif
 
 void test_network_remote_remotes__urlresolve_passthrough(void)
 {
+#ifndef GIT_DEPRECATE_HARD
 	git_buf url = GIT_BUF_INIT;
 	const char *orig_url = "git://github.com/libgit2/libgit2";
 
@@ -161,6 +168,7 @@ void test_network_remote_remotes__urlresolve_passthrough(void)
 	cl_assert_equal_s(url.ptr, orig_url);
 
 	git_buf_dispose(&url);
+#endif
 }
 
 void test_network_remote_remotes__instance_url(void)