git log -p -m: document -m and honor --first-parent
git log -p -m is used to show one merge entry per parent, with an
appropriate diff; this can be useful when examining histories where
full set of changes introduced by a merged branch is interesting, not
only the conflicts.
This patch properly documents the -m switch, which has so far been
mentioned only as a fairly special diff-tree flag.
It also makes the code show full patch entry only for the first parent
when --first-parent is used. Thus:
git log -p -m --first-parent
will show the history from the "main branch perspective", while also
including full diff of changes introduced by other merged in branches.
Signed-off-by: Petr Baudis <pasky@suse.cz>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/log-tree.c b/log-tree.c
index 27afcf6..d3ae969 100644
--- a/log-tree.c
+++ b/log-tree.c
@@ -514,6 +514,16 @@
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;
