fix uppercasing for U+A64B, CYRILLIC SMALL LETTER MONOGRAPH UK

* enc/unicode.c: Add U+A64B to the special cases 03B9 and 03BC
  at the end of onigenc_unicode_case_map (Bug #12990).

* enc/unicode/case-folding.rb: Add U+A64B to the special cases
  03B9 and 03BC. Add a comment pointing to enc/unicode.c.
  Change warnings to exceptions for unpredicted cases,
  because this would have been more easily noticed
  (the warning was not noticed when upgrading to Unicode 9.0.0).

* test/ruby/enc/test_case_comprehensive.rb: Remove temporary
  exclusion of U+A64B from testing.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@56941 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

enc/unicode.c

@@ -777,8 +777,8 @@ onigenc_unicode_case_map(OnigCaseFoldType* flagP,
 			code = folded->code[0];
 		}
 		else if ((flags&(ONIGENC_CASE_UPCASE))
-			 && (code==0x03B9||code==0x03BC)) { /* GREEK SMALL LETTERs IOTA/MU */
-		    MODIFIED;
+			 && (code==0x03B9||code==0x03BC||code==0xA64B)) { /* GREEK SMALL LETTERs IOTA/MU, */
+		    MODIFIED;                                             /* CYRILLIC SMALL LETTER MONOGRAPH UK */
 		    code = folded->code[1];
 		}
 	    }

enc/unicode/case-folding.rb

@@ -296,17 +296,19 @@ class CaseMapping
         when item.upper  then  flags += '|U'
         when item.lower  then  flags += '|D'
         else
-          unless from=='03B9' or from=='03BC'
-            warn 'Unpredicted case 0; check data or adjust program (enc/unicode/case_folding.rb).'
+          unless from=='03B9' or from=='03BC' or from=='A64B'
+            # cf. code==0x03B9||code==0x03BC||code==0xA64B in enc/unicode.c,
+            # towards the end of function onigenc_unicode_case_map
+            raise "Unpredicted case 0 in enc/unicode/case_folding.rb. Please contact https://bugs.ruby-lang.org/."
           end
         end
         unless item.upper == item.title
           if item.code == item.title
-            warn 'Unpredicted case 1; check data or adjust program (enc/unicode/case_folding.rb).'
+            raise "Unpredicted case 1 in enc/unicode/case_folding.rb. Please contact https://bugs.ruby-lang.org/."
           elsif item.title==to[1]
             flags += '|ST'
           else
-            warn 'Unpredicted case 2; check data or adjust program (enc/unicode/case_folding.rb).'
+            raise "Unpredicted case 2 in enc/unicode/case_folding.rb. Please contact https://bugs.ruby-lang.org/."
           end
         end
       end

test/ruby/enc/test_case_comprehensive.rb

@@ -146,8 +146,6 @@ TestComprehensiveCaseFold.data_files_available? and  class TestComprehensiveCase
       attributes.prepend '_' unless attributes.empty?
       define_method "test_#{encoding}_#{test.method_name}#{attributes}" do
         @@codepoints.each do |code|
-          next if code=="\uA64B" # temporarily exclude this character from testing,
-                                 # see https://bugs.ruby-lang.org/issues/12990
           source = code.encode(encoding) * 5
           target = "#{test.first_data[code]}#{test.follow_data[code]*4}".encode(encoding)
           result = source.__send__(test.method_name, *test.attributes)