MDEV-32454 JSON test has problem in view protocol.

Few Item_func_json_xxx::fix_length_and_dec() functions fixed.

mysql-test/main/func_json.result

@@ -272,7 +272,7 @@ create table t1 as select json_object('id', 87, 'name', 'carrot') as f;
 show create table t1;
 Table	Create Table
 t1	CREATE TABLE `t1` (
-  `f` varchar(32) DEFAULT NULL
+  `f` varchar(46) DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
 select * from t1;
 f

mysql-test/main/func_json.test

@@ -87,15 +87,12 @@ select json_extract('[10, 20, [30, 40], 1, 10]', '$[1]') as exp;
 select json_extract('[10, 20, [30, 40], 1, 10]', '$[1]', '$[25]') as exp;
 select json_extract( '[{"a": [3, 4]}, {"b": 2}]', '$[0].a', '$[1].a') as exp;
 
-#enable after MDEV-32454 fix
---disable_view_protocol
 select json_insert('{"a":1, "b":{"c":1}, "d":[1, 2]}', '$.b.k1', 'word') as exp;
 select json_insert('{"a":1, "b":{"c":1}, "d":[1, 2]}', '$.d[3]', 3) as exp;
 select json_insert('{"a":1, "b":{"c":1}, "d":[1, 2]}', '$.a[2]', 2) as exp;
 select json_insert('{"a":1, "b":{"c":1}, "d":[1, 2]}', '$.b.c', 'word') as exp;
 
 select json_set('{ "a": 1, "b": [2, 3]}', '$.a', 10, '$.c', '[true, false]') as exp;
---enable_view_protocol
 
 select json_replace('{ "a": 1, "b": [2, 3]}', '$.a', 10, '$.c', '[true, false]') as exp;
 select json_replace('{ "a": 1, "b": [2, 3]}', '$.a', 10, '$.b', '[true, false]') as exp;
@@ -137,14 +134,11 @@ select json_merge('a','b');
 select json_merge('{"a":"b"}','{"c":"d"}');
 SELECT JSON_MERGE('[1, 2]', '{"id": 47}');
 
-#enable after MDEV-32454 fix
---disable_view_protocol
 select json_type('{"k1":123, "k2":345}');
 select json_type('[123, "k2", 345]');
 select json_type("true");
 select json_type('123');
 select json_type('123.12');
---enable_view_protocol
 
 select json_keys('{"a":{"c":1, "d":2}, "b":2}');
 select json_keys('{"a":{"c":1, "d":2}, "b":2}', "$.a");
@@ -173,11 +167,8 @@ select json_search( json_col, 'all', 'foot' ) as ex from t1;
 drop table t1;
 
 
-#enable after MDEV-32454 fix
---disable_view_protocol
 select json_unquote('"abc"');
 select json_unquote('abc');
---enable_view_protocol
 #
 # MDEV-13703 Illegal mix of collations for operation 'json_object' on using JSON_UNQUOTE as an argument.
 #
@@ -188,13 +179,9 @@ select json_object('foo', json_unquote(json_object('bar', c)),'qux', c) as fld f
 drop table t1;
 
 
-#enable after MDEV-32454 fix
---disable_view_protocol
 select json_object("a", json_object("b", "abcd"));
 select json_object("a", '{"b": "abcd"}');
 select json_object("a", json_compact('{"b": "abcd"}'));
---enable_view_protocol
-
 
 select json_compact(NULL);
 select json_depth(json_compact(NULL));
@@ -270,11 +257,8 @@ select json_merge('{"a":{"u":12, "x":"b"}}', '{"a":{"x":"c"}}') as ex ;
 select json_merge('{"a":{"u":12, "x":"b", "r":1}}', '{"a":{"x":"c", "r":2}}') as ex ;
 
 select json_compact('{"a":1, "b":[1,2,3], "c":{"aa":"v1", "bb": "v2"}}') as ex;
-#enable after MDEV-32454 fix
---disable_view_protocol
 select json_loose('{"a":1, "b":[1,2,3], "c":{"aa":"v1", "bb": "v2"}}') as ex;
 select json_detailed('{"a":1, "b":[1,2,3], "c":{"aa":"v1", "bb": "v2"}}') as ex;
---enable_view_protocol
 
 #
 # MDEV-11856 json_search doesn't search for values with double quotes character (")
@@ -466,12 +450,9 @@ drop table t1;
 --echo # MDEV-16750 JSON_SET mishandles unicode every second pair of arguments.
 --echo #
 
-#enable after MDEV-32454 fix
---disable_view_protocol
 SELECT JSON_SET('{}', '$.a', _utf8 0xC3B6) as exp;
 SELECT JSON_SET('{}', '$.a', _utf8 0xC3B6, '$.b', _utf8 0xC3B6) as exp;
 SELECT JSON_SET('{}', '$.a', _utf8 X'C3B6', '$.x', 1, '$.b', _utf8 X'C3B6') as exp;
---enable_view_protocol
 
 --echo #
 --echo # MDEV-17121 JSON_ARRAY_APPEND

sql/item_jsonfunc.cc

@@ -761,7 +761,7 @@ bool Item_func_json_unquote::fix_length_and_dec()
 {
   collation.set(&my_charset_utf8_general_ci,
                 DERIVATION_COERCIBLE, MY_REPERTOIRE_ASCII);
-  max_length= args[0]->max_length;
+  max_length= args[0]->max_char_length() * collation.collation->mbmaxlen;
   maybe_null= 1;
   return FALSE;
 }
@@ -1730,7 +1730,22 @@ bool Item_func_json_array::fix_length_and_dec()
     return TRUE;
 
   for (n_arg=0 ; n_arg < arg_count ; n_arg++)
-    char_length+= args[n_arg]->max_char_length() + 4;
+  {
+    ulonglong arg_length;
+    Item *arg= args[n_arg];
+
+    if (!arg->is_json_type() && arg->result_type() == STRING_RESULT)
+      arg_length= arg->max_char_length() * 2; /*escaping possible */
+    else if (arg->type_handler()->is_bool_type())
+      arg_length= 5;
+    else
+      arg_length= arg->max_char_length();
+
+    if (arg_length < 4)
+      arg_length= 4; /* can be 'null' */
+
+    char_length+= arg_length + 4;
+  }
 
   fix_char_length_ulonglong(char_length);
   tmp_val.set_charset(collation.collation);
@@ -2874,7 +2889,7 @@ longlong Item_func_json_depth::val_int()
 bool Item_func_json_type::fix_length_and_dec()
 {
   collation.set(&my_charset_utf8_general_ci);
-  max_length= 12;
+  max_length= 12 * collation.collation->mbmaxlen;
   maybe_null= 1;
   return FALSE;
 }
@@ -2940,6 +2955,11 @@ bool Item_func_json_insert::fix_length_and_dec()
   for (n_arg= 1; n_arg < arg_count; n_arg+= 2)
   {
     paths[n_arg/2].set_constant_flag(args[n_arg]->const_item());
+    /*
+      In the resulting JSON we can insert the property
+      name from the path, and the value itself.
+    */
+    char_length+= args[n_arg/2]->max_char_length() + 6;
     char_length+= args[n_arg/2+1]->max_char_length() + 4;
   }
 
@@ -3749,7 +3769,20 @@ bool Item_func_json_format::fix_length_and_dec()
 {
   decimals= 0;
   collation.set(args[0]->collation);
-  max_length= args[0]->max_length;
+  switch (fmt)
+  {
+  case COMPACT:
+    max_length= args[0]->max_length;
+    break;
+  case LOOSE:
+    max_length= args[0]->max_length * 2;
+    break;
+  case DETAILED:
+    max_length= MAX_BLOB_WIDTH;
+    break;
+  default:
+    DBUG_ASSERT(0);
+  };
   maybe_null= 1;
   return FALSE;
 }