Bug#41084 full-text index added to custom UCA collation not working

Problem:
Custom UCA collations didn't set the MY_CS_STRNXFRM flag,
which resulted in "prefix_search" method instead of
the required "seq_search".

Problem2: (not metioned in the bug report)
Custom UCA collations didn't also set the MY_CS_UNICODE flag,
so an attempt to compare a column with a custom UCA collation
to another column with a non-Unicode character set led to
the "illegal mix of collation" error.

Fix:
the two missing flags was added into collation initialization.

  Upgrade:

  - All fulltext indexes with custom UCA collations should be rebuilt.

  - Non-fulltext custom UCA indexes should likely be rebuild as well.

mysql-test/r/ctype_ldml.result

@@ -21,6 +21,25 @@ select * from t1 where c1='b';
 c1
 a
 drop table t1;
+CREATE TABLE t1 (
+col1 varchar(100) character set utf8 collate utf8_test_ci
+);
+INSERT INTO t1 (col1) VALUES ('abcd'),('efgh'),('ijkl');
+ALTER TABLE t1 ADD FULLTEXT INDEX (col1);
+SELECT * FROM t1 where match (col1) against ('abcd');
+col1
+abcd
+SELECT * FROM t1 where match (col1) against ('abcd' IN BOOLEAN MODE);
+col1
+abcd
+ALTER TABLE t1 ADD (col2 varchar(100) character set latin1);
+UPDATE t1 SET col2=col1;
+SELECT * FROM t1 WHERE col1=col2 ORDER BY col1;
+col1	col2
+abcd	abcd
+efgh	efgh
+ijkl	ijkl
+DROP TABLE t1;
 show collation like 'ucs2_vn_ci';
 Collation	Charset	Id	Default	Compiled	Sortlen
 ucs2_vn_ci	ucs2	242			8

mysql-test/t/ctype_ldml.test

@@ -21,6 +21,22 @@ insert into t1 values ('a');
 select * from t1 where c1='b';
 drop table t1;
 
+
+#
+# Bug#41084 full-text index added to custom UCA collation not working
+#
+CREATE TABLE t1 (
+  col1 varchar(100) character set utf8 collate utf8_test_ci
+);
+INSERT INTO t1 (col1) VALUES ('abcd'),('efgh'),('ijkl');
+ALTER TABLE t1 ADD FULLTEXT INDEX (col1);
+SELECT * FROM t1 where match (col1) against ('abcd');
+SELECT * FROM t1 where match (col1) against ('abcd' IN BOOLEAN MODE);
+ALTER TABLE t1 ADD (col2 varchar(100) character set latin1);
+UPDATE t1 SET col2=col1;
+SELECT * FROM t1 WHERE col1=col2 ORDER BY col1;
+DROP TABLE t1;
+
 #
 #  Vietnamese experimental collation
 #

mysys/charset.c

@@ -212,6 +212,8 @@ copy_uca_collation(CHARSET_INFO *to, CHARSET_INFO *from)
   to->max_sort_char= from->max_sort_char;
   to->mbminlen= from->mbminlen;
   to->mbmaxlen= from->mbmaxlen;
+  to->state|= MY_CS_AVAILABLE | MY_CS_LOADED |
+              MY_CS_STRNXFRM  | MY_CS_UNICODE;
 }
 
 
@@ -246,14 +248,12 @@ static int add_collation(CHARSET_INFO *cs)
       {
 #if defined(HAVE_CHARSET_ucs2) && defined(HAVE_UCA_COLLATIONS)
         copy_uca_collation(newcs, &my_charset_ucs2_unicode_ci);
-        newcs->state|= MY_CS_AVAILABLE | MY_CS_LOADED;
 #endif        
       }
       else if (!strcmp(cs->csname, "utf8"))
       {
 #if defined (HAVE_CHARSET_utf8) && defined(HAVE_UCA_COLLATIONS)
         copy_uca_collation(newcs, &my_charset_utf8_unicode_ci);
-        newcs->state|= MY_CS_AVAILABLE | MY_CS_LOADED;
 #endif
       }
       else