JRuby does not have EXECUTABLE_EXTS in RbConfg::CONFIG

Author: nobu

lib/optparse.rb

@@ -1300,7 +1300,7 @@ def program_name
   private def strip_ext(name)  # :nodoc:
     exts = /#{
       require "rbconfig"
-      Regexp.union(RbConfig::CONFIG["EXECUTABLE_EXTS"])
+      Regexp.union(*RbConfig::CONFIG["EXECUTABLE_EXTS"]&.split(" "))
     }\z/o
     name.sub(exts, "")
   end

test/optparse/test_optparse.rb

@@ -221,7 +221,7 @@ def test_program_name
     program = $0
     $0 = "rdbg3.5"
     assert_equal "rdbg3.5", OptionParser.new.program_name
-    RbConfig::CONFIG["EXECUTABLE_EXTS"].split(" ") do |ext|
+    RbConfig::CONFIG["EXECUTABLE_EXTS"]&.split(" ") do |ext|
       $0 = "rdbg3.5" + ext
       assert_equal "rdbg3.5", OptionParser.new.program_name
     end