Merge branch 'rs/reflog-exists'

* rs/reflog-exists:
  checkout.c: use ref_exists instead of file_exist
  refs.c: add new functions reflog_exists and delete_reflog

t/t1410-reflog.sh

@@ -245,4 +245,12 @@ test_expect_success 'gc.reflogexpire=false' '
 
 '
 
+test_expect_success 'checkout should not delete log for packed ref' '
+	test $(git reflog master | wc -l) = 4 &&
+	git branch foo &&
+	git pack-refs --all &&
+	git checkout foo &&
+	test $(git reflog master | wc -l) = 4
+'
+
 test_done