A fix and a test case for Bug#26104 Bug on foreign key class constructor.

Fix the typo in the constructor. Cover a semantic check that previously
never worked with a test.

mysql-test/r/create.result

@@ -1503,4 +1503,20 @@ t1	CREATE TABLE `t1` (
   `c17` int(11) default NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 drop table t1;
+
+Bug #26104 Bug on foreign key class constructor
+
+Check that ref_columns is initalized correctly in the constructor
+and semantic checks in mysql_prepare_table work.
+
+We do not need a storage engine that supports foreign keys
+for this test, as the checks are purely syntax-based, and the
+syntax is supported for all engines.
+
+drop table if exists t1,t2;
+create table t1(a int not null, b int not null, primary key (a, b));
+create table t2(a int not null, b int not null, c int not null, primary key (a),
+foreign key fk_bug26104 (b,c) references t1(a));
+ERROR 42000: Incorrect foreign key definition for 'fk_bug26104': Key reference and table reference don't match
+drop table t1;
 End of 5.0 tests

mysql-test/r/innodb.result

@@ -1648,7 +1648,7 @@ t2	CREATE TABLE `t2` (
 ) ENGINE=InnoDB DEFAULT CHARSET=latin1
 drop table t2;
 create table t2 (id int(11) not null, id2 int(11) not null, constraint t1_id_fk foreign key (id2,id) references t1 (id)) engine = innodb;
-ERROR HY000: Can't create table './test/t2' (errno: 150)
+ERROR 42000: Incorrect foreign key definition for 't1_id_fk': Key reference and table reference don't match
 create table t2 (a int auto_increment primary key, b int, index(b), foreign key (b) references t1(id), unique(b)) engine=innodb;
 show create table t2;
 Table	Create Table

mysql-test/t/create.test

@@ -1118,5 +1118,24 @@ show create table t1;
 
 drop table t1;
 
+--echo
+--echo Bug #26104 Bug on foreign key class constructor
+--echo
+--echo Check that ref_columns is initalized correctly in the constructor
+--echo and semantic checks in mysql_prepare_table work.
+--echo
+--echo We do not need a storage engine that supports foreign keys
+--echo for this test, as the checks are purely syntax-based, and the
+--echo syntax is supported for all engines.
+--echo
+--disable_warnings
+drop table if exists t1,t2;
+--enable_warnings
+
+create table t1(a int not null, b int not null, primary key (a, b));
+--error ER_WRONG_FK_DEF
+create table t2(a int not null, b int not null, c int not null, primary key (a),
+foreign key fk_bug26104 (b,c) references t1(a));
+drop table t1;
 
 --echo End of 5.0 tests

mysql-test/t/innodb.test

@@ -1180,7 +1180,7 @@ drop table t2;
 # Clean up filename -- embedded server reports whole path without .frm,
 # regular server reports relative path with .frm (argh!)
 --replace_result \\ / $MYSQL_TEST_DIR . /var/master-data/ / t2.frm t2
---error 1005
+--error ER_WRONG_FK_DEF
 create table t2 (id int(11) not null, id2 int(11) not null, constraint t1_id_fk foreign key (id2,id) references t1 (id)) engine = innodb;
 
 # bug#3749

sql/sql_class.h

@@ -450,7 +450,7 @@ public:
 	      Table_ident *table,   List<key_part_spec> &ref_cols,
 	      uint delete_opt_arg, uint update_opt_arg, uint match_opt_arg)
     :Key(FOREIGN_KEY, name_arg, HA_KEY_ALG_UNDEF, 0, cols),
-    ref_table(table), ref_columns(cols),
+    ref_table(table), ref_columns(ref_cols),
     delete_opt(delete_opt_arg), update_opt(update_opt_arg),
     match_opt(match_opt_arg)
   {}