--- unicode.rb.orig	2020-10-01 05:15:38.000000000 -0700
+++ unicode.rb	2020-12-17 23:45:46.000000000 -0800
@@ -81,7 +81,8 @@
     when /^\p{M}/
       0
     when EastAsianWidth::TYPE_A
-      Reline.ambiguous_width
+      width = Reline.ambiguous_width
+      width.nil? ? 1 : width  # if nil then assume 1
     when EastAsianWidth::TYPE_F, EastAsianWidth::TYPE_W
       2
     when EastAsianWidth::TYPE_H, EastAsianWidth::TYPE_NA, EastAsianWidth::TYPE_N