surround %s with quotes when failed to lookup commit

The output may become confusing to recognize if the user
accidentally gave an extra opening space, like:

   $ git commit --fixup=" 6d6360b67e99c2fd82d64619c971fdede98ee74b"
   fatal: could not lookup commit  6d6360b67e99c2fd82d64619c971fdede98ee74b

and it will be better if we surround the %s specifier with single quotes.

Signed-off-by: Teng Long <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: dyrone

builtin/commit.c

@@ -763,7 +763,7 @@ static int prepare_to_commit(const char *index_file, const char *prefix,
 			struct commit *c;
 			c = lookup_commit_reference_by_name(squash_message);
 			if (!c)
-				die(_("could not lookup commit %s"), squash_message);
+				die(_("could not lookup commit '%s'"), squash_message);
 			ctx.output_encoding = get_commit_output_encoding();
 			repo_format_commit_message(the_repository, c,
 						   "squash! %s\n\n", &sb,
@@ -798,7 +798,7 @@ static int prepare_to_commit(const char *index_file, const char *prefix,
 		char *fmt;
 		commit = lookup_commit_reference_by_name(fixup_commit);
 		if (!commit)
-			die(_("could not lookup commit %s"), fixup_commit);
+			die(_("could not lookup commit '%s'"), fixup_commit);
 		ctx.output_encoding = get_commit_output_encoding();
 		fmt = xstrfmt("%s! %%s\n\n", fixup_prefix);
 		repo_format_commit_message(the_repository, commit, fmt, &sb,
@@ -1189,7 +1189,7 @@ static const char *read_commit_message(const char *name)
 
 	commit = lookup_commit_reference_by_name(name);
 	if (!commit)
-		die(_("could not lookup commit %s"), name);
+		die(_("could not lookup commit '%s'"), name);
 	out_enc = get_commit_output_encoding();
 	return repo_logmsg_reencode(the_repository, commit, NULL, out_enc);
 }

builtin/merge-tree.c

@@ -448,7 +448,7 @@ static int real_merge(struct merge_tree_options *o,
 
 		base_commit = lookup_commit_reference_by_name(merge_base);
 		if (!base_commit)
-			die(_("could not lookup commit %s"), merge_base);
+			die(_("could not lookup commit '%s'"), merge_base);
 
 		opt.ancestor = merge_base;
 		base_tree = repo_get_commit_tree(the_repository, base_commit);