diff --git a/ChangeLog b/ChangeLog
index 11e4246a59..01b455429f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Tue Jul 26 13:04:59 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
+
+	* test/ruby/enc/test_case_comprehensive.rb: Add explicit skip test for
+	  availability of Unicode data files.
+
 Mon Jul 25 21:33:13 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* range.c (check_step_domain): check step argument domain by <=>
diff --git a/test/ruby/enc/test_case_comprehensive.rb b/test/ruby/enc/test_case_comprehensive.rb
index 40f4327e63..2b93692317 100644
--- a/test/ruby/enc/test_case_comprehensive.rb
+++ b/test/ruby/enc/test_case_comprehensive.rb
@@ -14,12 +14,21 @@ class TestComprehensiveCaseFold < Test::Unit::TestCase
   def self.expand_filename(basename)
     File.expand_path("#{UNICODE_DATA_PATH}/#{basename}.txt", __dir__)
   end
+  
+  def self.data_files_available?
+    %w[UnicodeData CaseFolding SpecialCasing].all? do |f|
+      File.exist?(expand_filename(f))
+    end
+  end
+
+  def test_data_files_available
+    unless TestComprehensiveCaseFold.data_files_available?
+      skip "Unicode data files not available in #{UNICODE_DATA_PATH}."
+    end
+  end
 end
 
-%w[UnicodeData CaseFolding SpecialCasing].all? {|f|
-  File.exist?(TestComprehensiveCaseFold.expand_filename(f))
-} and
-class TestComprehensiveCaseFold
+TestComprehensiveCaseFold.data_files_available? and  class TestComprehensiveCaseFold
   (CaseTest = Struct.new(:method_name, :attributes, :first_data, :follow_data)).class_eval do
     def initialize(method_name, attributes, first_data, follow_data=first_data)
       super