Fix for bug #14360: Date Between Interval Broken.

mysql-test/r/innodb.result

@@ -3232,3 +3232,12 @@ drop trigger t2t;
 drop trigger t3t;
 drop trigger t4t;
 drop table t1, t2, t3, t4, t5;
+create table t1(a date) engine=innodb;
+create table t2(a date, key(a)) engine=innodb;
+insert into t1 values('2005-10-01');
+insert into t2 values('2005-10-01');
+select * from t1, t2
+where t2.a between t1.a - interval 2 day and t1.a + interval 2 day;
+a	a
+2005-10-01	2005-10-01
+drop table t1, t2;

mysql-test/t/innodb.test

@@ -2127,3 +2127,15 @@ drop table t1, t2, t3, t4, t5;
 connection default;
 disconnect a;
 disconnect b;
+
+#
+# Bug #14360: problem with intervals
+#
+
+create table t1(a date) engine=innodb;
+create table t2(a date, key(a)) engine=innodb; 
+insert into t1 values('2005-10-01');
+insert into t2 values('2005-10-01');
+select * from t1, t2
+  where t2.a between t1.a - interval 2 day and t1.a + interval 2 day;
+drop table t1, t2;

sql/item_timefunc.cc

@@ -2125,6 +2125,41 @@ longlong Item_date_add_interval::val_int()
     ((date*100L + ltime.hour)*100L+ ltime.minute)*100L + ltime.second;
 }
 
+
+
+bool Item_date_add_interval::eq(const Item *item, bool binary_cmp) const
+{
+  INTERVAL interval, other_interval;
+  String val= value;   // Because of const
+
+  if (this == item)
+    return TRUE;
+
+  if ((item->type() != FUNC_ITEM) ||
+      (arg_count != ((Item_func*) item)->arg_count) ||
+      (func_name() != ((Item_func*) item)->func_name()))
+    return FALSE;
+
+  Item_date_add_interval *other= (Item_date_add_interval*) item;
+
+  if ((int_type != other->int_type) ||
+      (!args[0]->eq(other->args[0], binary_cmp)) ||
+      (get_interval_value(args[1], int_type, &val, &interval)))
+    return FALSE;
+
+  val= other->value;
+
+  if ((get_interval_value(other->args[1], other->int_type, &val,
+                         &other_interval)) ||
+      ((date_sub_interval ^ interval.neg) ^
+       (other->date_sub_interval ^ other_interval.neg)))
+    return FALSE;
+
+  // Assume comparing same types here due to earlier check
+  return memcmp(&interval, &other_interval, sizeof(INTERVAL)) == 0;
+}
+
+
 static const char *interval_names[]=
 {
   "year", "quarter", "month", "day", "hour",

sql/item_timefunc.h

@@ -656,6 +656,7 @@ class Item_date_add_interval :public Item_date_func
   double val_real() { DBUG_ASSERT(fixed == 1); return (double) val_int(); }
   longlong val_int();
   bool get_date(TIME *res, uint fuzzy_date);
+  bool eq(const Item *item, bool binary_cmp) const;
   void print(String *str);
 };