added test

querydsl-core/src/test/java/com/mysema/query/types/PredicateOperationTest.java

@@ -0,0 +1,18 @@
+package com.mysema.query.types;
+
+import static org.junit.Assert.assertEquals;
+
+import org.junit.Test;
+
+public class PredicateOperationTest {
+
+    @SuppressWarnings("unchecked")
+    @Test
+    public void Not() {
+        Path o1 = new PathImpl(Object.class, "o1");
+        Path o2 = new PathImpl(Object.class, "o2");
+        PredicateOperation template = new PredicateOperation(Ops.EQ_OBJECT, o1, o2);
+        assertEquals("!o1 = o2", template.not().toString());
+    }
+
+}