Introduce git_merge__extract_conflict_paths

src/merge.c

@@ -2469,6 +2469,47 @@ done:
 	return error;
 }
 
+int git_merge__append_conflicts_to_merge_msg(
+	git_repository *repo,
+	git_index *index)
+{
+	git_filebuf file = GIT_FILEBUF_INIT;
+	git_buf file_path = GIT_BUF_INIT;
+	const char *last = NULL;
+	size_t i;
+	int error;
+
+	if ((error = git_buf_joinpath(&file_path, repo->path_repository, GIT_MERGE_MSG_FILE)) < 0 ||
+		(error = git_filebuf_open(&file, file_path.ptr, GIT_FILEBUF_APPEND, GIT_MERGE_FILE_MODE)) < 0)
+		goto cleanup;
+
+	if (git_index_has_conflicts(index))
+		git_filebuf_printf(&file, "\nConflicts:\n");
+
+	for (i = 0; i < git_index_entrycount(index); i++) {
+		const git_index_entry *e = git_index_get_byindex(index, i);
+
+		if (git_index_entry_stage(e) == 0)
+			continue;
+
+		if (last == NULL || strcmp(e->path, last) != 0)
+			git_filebuf_printf(&file, "\t%s\n", e->path);
+
+		last = e->path;
+	}
+
+	error = git_filebuf_commit(&file);
+
+cleanup:
+	if (error < 0)
+		git_filebuf_cleanup(&file);
+
+	git_buf_free(&file_path);
+
+	return error;
+}
+
+
 static int merge_state_cleanup(git_repository *repo)
 {
 	const char *state_files[] = {

src/merge.h

@@ -151,4 +151,6 @@ int git_merge__setup(
 
 int git_merge__indexes(git_repository *repo, git_index *index_new);
 
+int git_merge__append_conflicts_to_merge_msg(git_repository *repo, git_index *index);
+
 #endif