Documentation/rev-list-options.txt: Explain --ancestry-path

diff --git a/log-tree.c b/log-tree.c
index 27afcf697238a48c01dd49996f5263cd72a52eac..d3ae969f608b50a469aa60b2e925558a6bb437e5 100644 (file)
--- a/log-tree.c
+++ b/log-tree.c
@@ -514,6 +514,16 @@ static int log_tree_diff(struct rev_info *opt, struct commit *commit, struct log
                        return 0;
                else if (opt->combine_merges)
                        return do_diff_combined(opt, commit);
+               else if (opt->first_parent_only) {
+                       /*
+                        * Generate merge log entry only for the first
+                        * parent, showing summary diff of the others
+                        * we merged _in_.
+                        */
+                       diff_tree_sha1(parents->item->object.sha1, sha1, "", &opt->diffopt);
+                       log_tree_diff_flush(opt);
+                       return !opt->loginfo;
+               }
 
                /* If we show individual diffs, show the parent info */
                log->parent = parents->item;