patch 7.4.1970
Problem:    Using ":insert" in an empty buffer sets the jump mark. (Ingo
            Karkat)
Solution:   Don't adjust marks when replacing the empty line in an empty
            buffer. (closes #892)
diff --git a/src/testdir/test_jumps.vim b/src/testdir/test_jumps.vim
new file mode 100644
index 0000000..5a3717d
--- /dev/null
+++ b/src/testdir/test_jumps.vim
@@ -0,0 +1,11 @@
+func Test_empty_buffer()
+  new
+  insert
+a
+b
+c
+d
+.
+  call assert_equal(1, line("''"))
+  bwipe!
+endfunc