On Fri, Dec 11, 2020 at 01:27:04AM +0100, Stefan Sperling wrote:
> If the histedit log message editor exits without saving its buffer,
> we currently throw away log messages of all commits which were folded.
> Only the last commit message is preserved, which could be something
> meaningless like "fixup".
> 
> This patch makes us preserve the initial editor buffer content as-is.
> That's not going to be an ideal log message, but doesn't throw away
> information and stands out visually because the newly created log
> message will start with a comment like:
> [[[
> # log message of folded commit aabbcc00...
> ]]]
> 
> Git's approach is to concatentate all log messages and strip comments.
> That has other downsides such as resulting in a potentially nonsensical
> log message.
> I'd like to stick to a simple "what you see is what you get" approach.
>  
> Problem reported by jrick
> 
> ok?

Off-list, jrick suggested to keep the behaviour intact where histedit's
commit operation is aborted if the saved log message is empty.

Differentiating between "empty message" and "unchanged message" should
be a good thing to do in general.

ok?

(This is the same change as the previous patch but with the empty log
message behaviour kept as-is.)

diff a2c1255649ab1b8d0fc66ec6ff07646b6176e764 e559f03aa5e4b408dced5ddbbcfd102692d19a36
blob - 7bdd9e142a5f26254c73c308684bb6d6da95ef20
blob + c8dbc08063b2590cb230bbb89b7864078f5b1a4d
--- got/got.c
+++ got/got.c
@@ -448,7 +448,7 @@ edit_logmsg(char **logmsg, const char *editor, const c
 		return got_error_from_errno("stat");
 
 	if (st.st_mtime == st2.st_mtime && st.st_size == st2.st_size)
-		return got_error_msg(GOT_ERR_COMMIT_MSG_EMPTY,
+		return got_error_msg(GOT_ERR_COMMIT_MSG_NOCHANGE,
 		    "no changes made to commit message, aborting");
 
 	/*
@@ -521,7 +521,7 @@ edit_logmsg(char **logmsg, const char *editor, const c
 		goto done;
 	}
 	if (strcmp(*logmsg, initial_content_stripped) == 0)
-		err = got_error_msg(GOT_ERR_COMMIT_MSG_EMPTY,
+		err = got_error_msg(GOT_ERR_COMMIT_MSG_NOCHANGE,
 		    "no changes made to commit message, aborting");
 done:
 	free(initial_content_stripped);
@@ -803,6 +803,7 @@ cmd_import(int argc, char *argv[])
 		    path_dir, refname);
 		if (error) {
 			if (error->code != GOT_ERR_COMMIT_MSG_EMPTY &&
+			    error->code != GOT_ERR_COMMIT_MSG_NOCHANGE &&
 			    logmsg_path != NULL)
 				preserve_logmsg = 1;
 			goto done;
@@ -5971,6 +5972,7 @@ add_tag(struct got_repository *repo, struct got_worktr
 		    tag_name, got_repo_get_path(repo));
 		if (err) {
 			if (err->code != GOT_ERR_COMMIT_MSG_EMPTY &&
+			    err->code != GOT_ERR_COMMIT_MSG_NOCHANGE &&
 			    tagmsg_path != NULL)
 				preserve_tagmsg = 1;
 			goto done;
@@ -6904,6 +6906,7 @@ cmd_commit(int argc, char *argv[])
 	    print_status, NULL, repo);
 	if (error) {
 		if (error->code != GOT_ERR_COMMIT_MSG_EMPTY &&
+		    error->code != GOT_ERR_COMMIT_MSG_NOCHANGE &&
 		    cl_arg.logmsg_path != NULL)
 			preserve_logmsg = 1;
 		goto done;
@@ -8016,9 +8019,12 @@ histedit_edit_logmsg(struct got_histedit_list_entry *h
 	err = edit_logmsg(&hle->logmsg, editor, logmsg_path, logmsg,
 	    logmsg_len);
 	if (err) {
-		if (err->code != GOT_ERR_COMMIT_MSG_EMPTY)
+		if (err->code != GOT_ERR_COMMIT_MSG_NOCHANGE)
 			goto done;
-		err = got_object_commit_get_logmsg(&hle->logmsg, commit);
+		err = NULL;
+		hle->logmsg = strdup(new_msg);
+		if (hle->logmsg == NULL)
+			err = got_error_from_errno("strdup");
 	}
 done:
 	if (logmsg_path && unlink(logmsg_path) != 0 && err == NULL)
blob - 5fa8ffa0d2de4c2d61942eb2eed66a240149f6d0
blob + cfef35362eff7e295b62a678e352388f674a4b43
--- include/got_error.h
+++ include/got_error.h
@@ -109,7 +109,7 @@
 #define GOT_ERR_NO_HISTEDIT_CMD	92
 #define GOT_ERR_HISTEDIT_SYNTAX	93
 #define GOT_ERR_HISTEDIT_CANCEL	94
-/* 95 is currently unused */
+#define GOT_ERR_COMMIT_MSG_NOCHANGE 95
 #define GOT_ERR_HISTEDIT_BUSY	96
 #define GOT_ERR_HISTEDIT_CMD	97
 #define GOT_ERR_HISTEDIT_PATH	98
@@ -252,7 +252,7 @@ static const struct got_error {
 	{ GOT_ERR_NO_HISTEDIT_CMD,"no histedit commands provided" },
 	{ GOT_ERR_HISTEDIT_SYNTAX,"syntax error in histedit command list" },
 	{ GOT_ERR_HISTEDIT_CANCEL,"histedit operation cancelled" },
-	{ 95, "unused error code" },
+	{ GOT_ERR_COMMIT_MSG_NOCHANGE, "no changes made to commit message" },
 	{ GOT_ERR_HISTEDIT_BUSY,"histedit operation is in progress in this "
 	    "work tree and must be continued or aborted first" },
 	{ GOT_ERR_HISTEDIT_CMD, "bad histedit command" },