Disallow file separator in version strings.

Library/Homebrew/cask/lib/hbc/audit.rb

@@ -60,6 +60,7 @@ module Hbc
     def check_version
       return unless cask.version
       check_no_string_version_latest
+      check_no_file_separator_in_version
     end
 
     def check_no_string_version_latest
@@ -68,6 +69,13 @@ module Hbc
       add_error "you should use version :latest instead of version 'latest'"
     end
 
+    def check_no_file_separator_in_version
+      odebug "Verifying version does not contain '#{File::SEPARATOR}'"
+      return unless cask.version.raw_version.is_a?(String)
+      return unless cask.version.raw_version.include?(File::SEPARATOR)
+      add_error "version should not contain '#{File::SEPARATOR}'"
+    end
+
     def check_sha256
       return unless cask.sha256
       check_sha256_no_check_if_latest