Some more functions work according to coercibility now:

repeat, reverse, quote, soundex, substring
Test func_str has been extended to check them

mysql-test/r/func_str.result

@@ -288,6 +288,21 @@ latin2_general_ci	3
 select collation(trim(BOTH _latin2' ' FROM _latin2'a')), coercibility(trim(BOTH _latin2'a' FROM _latin2'a'));
 collation(trim(BOTH _latin2' ' FROM _latin2'a'))	coercibility(trim(BOTH _latin2'a' FROM _latin2'a'))
 latin2_general_ci	3
+select collation(repeat(_latin2'a',10)), coercibility(repeat(_latin2'a',10));
+collation(repeat(_latin2'a',10))	coercibility(repeat(_latin2'a',10))
+latin2_general_ci	3
+select collation(reverse(_latin2'ab')), coercibility(reverse(_latin2'ab'));
+collation(reverse(_latin2'ab'))	coercibility(reverse(_latin2'ab'))
+latin2_general_ci	3
+select collation(quote(_latin2'ab')), coercibility(quote(_latin2'ab'));
+collation(quote(_latin2'ab'))	coercibility(quote(_latin2'ab'))
+latin2_general_ci	3
+select collation(soundex(_latin2'ab')), coercibility(soundex(_latin2'ab'));
+collation(soundex(_latin2'ab'))	coercibility(soundex(_latin2'ab'))
+latin2_general_ci	3
+select collation(substring(_latin2'ab',1)), coercibility(substring(_latin2'ab',1));
+collation(substring(_latin2'ab',1))	coercibility(substring(_latin2'ab',1))
+latin2_general_ci	3
 create table t1 
 select
 left(_latin2'a',1),
@@ -302,7 +317,12 @@ ltrim(_latin2' a '),
 rtrim(_latin2' a '),
 trim(LEADING _latin2' ' FROM _latin2' a '),
 trim(TRAILING _latin2' ' FROM _latin2' a '),
-trim(BOTH _latin2' ' FROM _latin2' a ')
+trim(BOTH _latin2' ' FROM _latin2' a '),
+repeat(_latin2'a',10),
+reverse(_latin2'ab'),
+quote(_latin2'ab'),
+soundex(_latin2'ab'),
+substring(_latin2'ab',1)
 ;
 show create table t1;
 Table	Create Table
@@ -319,6 +339,11 @@ t1	CREATE TABLE `t1` (
   `rtrim(_latin2' a ')` char(3) character set latin2 NOT NULL default '',
   `trim(LEADING _latin2' ' FROM _latin2' a ')` char(3) character set latin2 NOT NULL default '',
   `trim(TRAILING _latin2' ' FROM _latin2' a ')` char(3) character set latin2 NOT NULL default '',
-  `trim(BOTH _latin2' ' FROM _latin2' a ')` char(3) character set latin2 NOT NULL default ''
+  `trim(BOTH _latin2' ' FROM _latin2' a ')` char(3) character set latin2 NOT NULL default '',
+  `repeat(_latin2'a',10)` char(10) character set latin2 NOT NULL default '',
+  `reverse(_latin2'ab')` char(2) character set latin2 NOT NULL default '',
+  `quote(_latin2'ab')` char(6) character set latin2 NOT NULL default '',
+  `soundex(_latin2'ab')` char(4) character set latin2 NOT NULL default '',
+  `substring(_latin2'ab',1)` char(2) character set latin2 NOT NULL default ''
 ) TYPE=MyISAM CHARSET=latin1
 drop table t1;

mysql-test/t/func_str.test

@@ -149,6 +149,12 @@ select collation(rtrim(_latin2' a ')), coercibility(rtrim(_latin2' a '));
 select collation(trim(LEADING _latin2' ' FROM _latin2'a')), coercibility(trim(LEADING _latin2'a' FROM _latin2'a'));
 select collation(trim(TRAILING _latin2' ' FROM _latin2'a')), coercibility(trim(TRAILING _latin2'a' FROM _latin2'a'));
 select collation(trim(BOTH _latin2' ' FROM _latin2'a')), coercibility(trim(BOTH _latin2'a' FROM _latin2'a'));
+select collation(repeat(_latin2'a',10)), coercibility(repeat(_latin2'a',10));
+select collation(reverse(_latin2'ab')), coercibility(reverse(_latin2'ab'));
+select collation(quote(_latin2'ab')), coercibility(quote(_latin2'ab'));
+select collation(soundex(_latin2'ab')), coercibility(soundex(_latin2'ab'));
+select collation(substring(_latin2'ab',1)), coercibility(substring(_latin2'ab',1));
+
 create table t1 
 select
   left(_latin2'a',1),
@@ -163,7 +169,12 @@ select
   rtrim(_latin2' a '),
   trim(LEADING _latin2' ' FROM _latin2' a '),
   trim(TRAILING _latin2' ' FROM _latin2' a '),
-  trim(BOTH _latin2' ' FROM _latin2' a ')
+  trim(BOTH _latin2' ' FROM _latin2' a '),
+  repeat(_latin2'a',10),
+  reverse(_latin2'ab'),
+  quote(_latin2'ab'),
+  soundex(_latin2'ab'),
+  substring(_latin2'ab',1)
 ;
 
 show create table t1;

sql/item_cmpfunc.h

@@ -263,13 +263,6 @@ class Item_func_strcmp :public Item_bool_func2
 public:
   Item_func_strcmp(Item *a,Item *b) :Item_bool_func2(a,b) {}
   longlong val_int();
-  void fix_length_and_dec()
-  {
-    max_length=2;
-    /* QQ: COERCIBILITY */
-    cmp_charset= args[0]->binary() || args[1]->binary() ? 
-    		 &my_charset_bin : args[0]->charset();
-  }
   optimize_type select_optimize() const { return OPTIMIZE_NONE; }
   const char *func_name() const { return "strcmp"; }
 };

sql/item_strfunc.cc

@@ -702,6 +702,7 @@ String *Item_func_reverse::val_str(String *str)
 
 void Item_func_reverse::fix_length_and_dec()
 {
+  set_charset(args[0]->charset(),args[0]->coercibility);
   max_length = args[0]->max_length;
 }
 
@@ -1521,6 +1522,7 @@ String *Item_func_user::val_str(String *str)
 
 void Item_func_soundex::fix_length_and_dec()
 {
+  set_charset(args[0]->charset(), args[0]->coercibility);
   max_length=args[0]->max_length;
   set_if_bigger(max_length,4);
 }
@@ -1552,7 +1554,7 @@ String *Item_func_soundex::val_str(String *str)
 {
   String *res  =args[0]->val_str(str);
   char last_ch,ch;
-  CHARSET_INFO *cs= &my_charset_latin1;
+  CHARSET_INFO *cs= charset();
 
   if ((null_value=args[0]->null_value))
     return 0; /* purecov: inspected */
@@ -2538,6 +2540,7 @@ String *Item_func_quote::val_str(String *str)
   }
   *to= '\'';
   str->length(new_length);
+  str->set_charset(charset());
   return str;
 
 null:

sql/item_strfunc.h

@@ -571,7 +571,11 @@ class Item_func_quote :public Item_str_func
   Item_func_quote(Item *a) :Item_str_func(a) {}
   const char *func_name() const { return "quote"; }
   String *val_str(String *);
-  void fix_length_and_dec() { max_length= args[0]->max_length * 2 + 2; }
+  void fix_length_and_dec() 
+  { 
+    set_charset(args[0]->charset(), args[0]->coercibility);
+    max_length= args[0]->max_length * 2 + 2; 
+  }
 };
 
 class Item_func_conv_charset :public Item_str_func