Item::print(): remove redundant parentheses

by introducing new Item::precedence() method and using it
to decide whether parentheses are required

1 files changed, 6 insertions, 11 deletions

diff --git a/sql/item_func.cc b/sql/item_func.cc
index 64e4db80aa9..9bafe25e431 100644
--- a/sql/item_func.cc
+++ b/sql/item_func.cc
@@ -471,16 +471,14 @@ void Item_func::print_args(String *str, uint from, enum_query_type query_type)
 
 void Item_func::print_op(String *str, enum_query_type query_type)
 {
-  str->append('(');
   for (uint i=0 ; i < arg_count-1 ; i++)
   {
-    args[i]->print(str, query_type);
+    args[i]->print_parenthesised(str, query_type, precedence());
     str->append(' ');
     str->append(func_name());
     str->append(' ');
   }
-  args[arg_count-1]->print(str, query_type);
-  str->append(')');
+  args[arg_count-1]->print_parenthesised(str, query_type, precedence());
 }
 
 
@@ -5245,11 +5243,10 @@ bool Item_func_set_user_var::is_null_result()
 
 void Item_func_set_user_var::print(String *str, enum_query_type query_type)
 {
-  str->append(STRING_WITH_LEN("(@"));
+  str->append(STRING_WITH_LEN("@"));
   str->append(name.str, name.length);
   str->append(STRING_WITH_LEN(":="));
-  args[0]->print(str, query_type);
-  str->append(')');
+  args[0]->print_parenthesised(str, query_type, precedence());
 }
 
 
@@ -5259,8 +5256,7 @@ void Item_func_set_user_var::print_as_stmt(String *str,
   str->append(STRING_WITH_LEN("set @"));
   str->append(name.str, name.length);
   str->append(STRING_WITH_LEN(":="));
-  args[0]->print(str, query_type);
-  str->append(')');
+  args[0]->print_parenthesised(str, query_type, precedence());
 }
 
 bool Item_func_set_user_var::send(Protocol *protocol, String *str_arg)
@@ -5629,9 +5625,8 @@ bool Item_func_get_user_var::const_item() const
 
 void Item_func_get_user_var::print(String *str, enum_query_type query_type)
 {
-  str->append(STRING_WITH_LEN("(@"));
+  str->append(STRING_WITH_LEN("@"));
   append_identifier(current_thd, str, name.str, name.length);
-  str->append(')');
 }