Fix ValueInterval.negate()

h2/src/main/org/h2/value/ValueInterval.java

@@ -296,7 +296,7 @@ public class ValueInterval extends Value {
         if (leading == 0L && remaining == 0L) {
             return this;
         }
-        return from(getQualifier(), !negative, -leading, remaining);
+        return from(getQualifier(), !negative, leading, remaining);
     }
 
 }

h2/src/test/org/h2/test/scripts/datatypes/interval.sql

@@ -679,6 +679,9 @@ SELECT INTERVAL '1-2' YEAR TO MONTH + TIMESTAMP WITH TIME ZONE '2000-01-01 12:00
 SELECT TIMESTAMP WITH TIME ZONE '2000-01-01 12:00:00+01' - INTERVAL '1-2' YEAR TO MONTH;
 >> 1998-11-01 12:00:00+01
 
+SELECT -INTERVAL '1' DAY;
+>> INTERVAL '-1' DAY
+
 -- Date-time subtraction
 
 SELECT TIME '10:30:15.123456789' - TIME '11:00:00';