[PATCH 06/11] reset_head(): make default_reflog_action optional

["Phillip Wood via GitGitGadget" <gitgitgadget@gmail.com>]

From: Phillip Wood <phillip.wood@dunelm.org.uk>

This parameter is only needed when a ref is going to be updated and
the caller does not pass an explicit reflog message. Callers that are
just discarding changes in the working tree like create_autostash() do
not update any refs so should not have to worry about passing this
parameter.

Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
---
 builtin/merge.c  |  6 ++----
 builtin/rebase.c | 14 ++++++--------
 reset.c          | 16 ++++++++++++----
 sequencer.c      |  6 +++---
 sequencer.h      |  3 +--
 5 files changed, 24 insertions(+), 21 deletions(-)

diff --git a/builtin/merge.c b/builtin/merge.c
index d2c52b6e971..35833a963fc 100644
--- a/builtin/merge.c
+++ b/builtin/merge.c
@@ -1561,8 +1561,7 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
 
 		if (autostash)
 			create_autostash(the_repository,
-					 git_path_merge_autostash(the_repository),
-					 "merge");
+					 git_path_merge_autostash(the_repository));
 		if (checkout_fast_forward(the_repository,
 					  &head_commit->object.oid,
 					  &commit->object.oid,
@@ -1632,8 +1631,7 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
 
 	if (autostash)
 		create_autostash(the_repository,
-				 git_path_merge_autostash(the_repository),
-				 "merge");
+				 git_path_merge_autostash(the_repository));
 
 	/* We are going to make a new commit. */
 	git_committer_info(IDENT_STRICT);
diff --git a/builtin/rebase.c b/builtin/rebase.c
index 26f53c55cc4..1a6af508f49 100644
--- a/builtin/rebase.c
+++ b/builtin/rebase.c
@@ -791,8 +791,7 @@ static int move_to_original_branch(struct rebase_options *opts)
 		    opts->head_name);
 	ret = reset_head(the_repository, NULL, opts->head_name,
 			 RESET_HEAD_REFS_ONLY,
-			 orig_head_reflog.buf, head_reflog.buf,
-			 DEFAULT_REFLOG_ACTION);
+			 orig_head_reflog.buf, head_reflog.buf, NULL);
 
 	strbuf_release(&orig_head_reflog);
 	strbuf_release(&head_reflog);
@@ -1109,7 +1108,7 @@ static int checkout_up_to_date(struct rebase_options *options)
 		    options->switch_to);
 	if (reset_head(the_repository, &options->orig_head,
 		       options->head_name, RESET_HEAD_RUN_POST_CHECKOUT_HOOK,
-		       NULL, buf.buf, DEFAULT_REFLOG_ACTION) < 0)
+		       NULL, buf.buf, NULL) < 0)
 		ret = error(_("could not switch to %s"), options->switch_to);
 	strbuf_release(&buf);
 
@@ -1558,7 +1557,7 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
 		string_list_clear(&merge_rr, 1);
 
 		if (reset_head(the_repository, NULL, NULL, RESET_HEAD_HARD,
-			       NULL, NULL, DEFAULT_REFLOG_ACTION) < 0)
+			       NULL, NULL, NULL) < 0)
 			die(_("could not discard worktree changes"));
 		remove_branch_state(the_repository, 0);
 		if (read_basic_state(&options))
@@ -1964,8 +1963,8 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
 		die(_("could not read index"));
 
 	if (options.autostash) {
-		create_autostash(the_repository, state_dir_path("autostash", &options),
-				 DEFAULT_REFLOG_ACTION);
+		create_autostash(the_repository,
+				 state_dir_path("autostash", &options));
 	}
 
 	if (require_clean_work_tree(the_repository, "rebase",
@@ -2083,8 +2082,7 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
 			options.head_name ? options.head_name : "detached HEAD",
 			oid_to_hex(&options.onto->object.oid));
 		reset_head(the_repository, NULL, options.head_name,
-			   RESET_HEAD_REFS_ONLY, "HEAD", msg.buf,
-			   DEFAULT_REFLOG_ACTION);
+			   RESET_HEAD_REFS_ONLY, "HEAD", msg.buf, NULL);
 		strbuf_release(&msg);
 		ret = finish_rebase(&options);
 		goto cleanup;
diff --git a/reset.c b/reset.c
index 668c7639127..be4e18eed98 100644
--- a/reset.c
+++ b/reset.c
@@ -21,8 +21,13 @@ static int update_refs(const struct object_id *oid, const char *switch_to_branch
 	size_t prefix_len;
 	int ret;
 
-	reflog_action = getenv(GIT_REFLOG_ACTION_ENVIRONMENT);
-	strbuf_addf(&msg, "%s: ", reflog_action ? reflog_action : default_reflog_action);
+	if ((update_orig_head && !reflog_orig_head) || !reflog_head) {
+		if (!default_reflog_action)
+			BUG("default_reflog_action must be given when reflog messages are omitted");
+		reflog_action = getenv(GIT_REFLOG_ACTION_ENVIRONMENT);
+		strbuf_addf(&msg, "%s: ", reflog_action ? reflog_action :
+							  default_reflog_action);
+	}
 	prefix_len = msg.len;
 
 	if (update_orig_head) {
@@ -71,6 +76,7 @@ int reset_head(struct repository *r, struct object_id *oid,
 {
 	unsigned reset_hard = flags & RESET_HEAD_HARD;
 	unsigned refs_only = flags & RESET_HEAD_REFS_ONLY;
+	unsigned update_orig_head = flags & RESET_ORIG_HEAD;
 	struct object_id head_oid;
 	struct tree_desc desc[2] = { { NULL }, { NULL } };
 	struct lock_file lock = LOCK_INIT;
@@ -141,8 +147,10 @@ int reset_head(struct repository *r, struct object_id *oid,
 		goto leave_reset_head;
 	}
 
-	ret = update_refs(oid, switch_to_branch, reflog_head, reflog_orig_head,
-			  default_reflog_action, flags);
+	if (oid != &head_oid || update_orig_head || switch_to_branch)
+		ret = update_refs(oid, switch_to_branch, reflog_head,
+				  reflog_orig_head, default_reflog_action,
+				  flags);
 
 leave_reset_head:
 	rollback_lock_file(&lock);
diff --git a/sequencer.c b/sequencer.c
index 07d2a582d39..56a204f18c5 100644
--- a/sequencer.c
+++ b/sequencer.c
@@ -4093,8 +4093,8 @@ static enum todo_command peek_command(struct todo_list *todo_list, int offset)
 	return -1;
 }
 
-void create_autostash(struct repository *r, const char *path,
-		      const char *default_reflog_action)
+void create_autostash(struct repository *r, const char *path)
+
 {
 	struct strbuf buf = STRBUF_INIT;
 	struct lock_file lock_file = LOCK_INIT;
@@ -4131,7 +4131,7 @@ void create_autostash(struct repository *r, const char *path,
 		write_file(path, "%s", oid_to_hex(&oid));
 		printf(_("Created autostash: %s\n"), buf.buf);
 		if (reset_head(r, NULL, NULL, RESET_HEAD_HARD, NULL, NULL,
-			       default_reflog_action) < 0)
+			       NULL) < 0)
 			die(_("could not reset --hard"));
 
 		if (discard_index(r->index) < 0 ||
diff --git a/sequencer.h b/sequencer.h
index 2088344cb37..92357536ff4 100644
--- a/sequencer.h
+++ b/sequencer.h
@@ -198,8 +198,7 @@ void commit_post_rewrite(struct repository *r,
 			 const struct commit *current_head,
 			 const struct object_id *new_head);
 
-void create_autostash(struct repository *r, const char *path,
-		      const char *default_reflog_action);
+void create_autostash(struct repository *r, const char *path);
 int save_autostash(const char *path);
 int apply_autostash(const char *path);
 int apply_autostash_oid(const char *stash_oid);
-- 
gitgitgadget