Use custom deserializer for Event class

Using newer streaming versions of Gson causes deserialization
problems if the payload is before the type field in the returned
JSON using the current custom Event formatting.

This changes the behavior to use an internal custom Gson instance
just to handle parsing events that allows a chance to check the
type and create the custom payload before the Event object is
returned to any service callers.

This approach simplifies the code but does require an additional
Gson instance to be kept around to handle the default serialization
of the top-level Event fields.

Change-Id: Ic10a755bbf798ec2d1d4a4c53ccd9154e0cb91e2

1 files changed, 37 insertions, 17 deletions

diff --git a/org.eclipse.egit.github.core.tests/src/org/eclipse/egit/github/core/tests/EventFormatterTest.java b/org.eclipse.egit.github.core.tests/src/org/eclipse/egit/github/core/tests/EventFormatterTest.java
index d507f30d..0777f58d 100644
--- a/org.eclipse.egit.github.core.tests/src/org/eclipse/egit/github/core/tests/EventFormatterTest.java
+++ b/org.eclipse.egit.github.core.tests/src/org/eclipse/egit/github/core/tests/EventFormatterTest.java
@@ -10,45 +10,65 @@
  *******************************************************************************/
 package org.eclipse.egit.github.core.tests;
 
+import static org.eclipse.egit.github.core.event.Event.TYPE_FOLLOW;
+import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.assertNull;
 
 import org.eclipse.egit.github.core.client.EventFormatter;
+import org.eclipse.egit.github.core.client.GsonUtils;
+import org.eclipse.egit.github.core.event.Event;
 import org.eclipse.egit.github.core.event.EventPayload;
+import org.eclipse.egit.github.core.event.FollowPayload;
 import org.junit.Test;
 
 /**
- * Unit tests of {@link EventFormatter} and subclasses
+ * Unit tests of {@link EventFormatter}
  */
 public class EventFormatterTest {
 
 	/**
-	 * Create instance of EventFormatter
+	 * Follow event payload returned as {@link FollowPayload}
 	 */
 	@Test
-	public void createEventFormatterInstance() {
-		EventFormatter formatter = new EventFormatter();
-		assertNotNull(formatter.getEventCreator());
-		assertNotNull(formatter.getPayloadDeserializer());
+	public void followPayload() {
+		Event event = GsonUtils.fromJson("{\"type\":\"" + TYPE_FOLLOW
+				+ "\",\"payload\":{}}", Event.class);
+		assertNotNull(event);
+		assertNotNull(event.getPayload());
+		assertEquals(FollowPayload.class, event.getPayload().getClass());
 	}
 
 	/**
-	 * Create instance of Event
+	 * Unknown event payload returned as {@link EventPayload}
 	 */
 	@Test
-	public void createEventInstance() {
-		EventFormatter formatter = new EventFormatter();
-		assertNotNull(formatter.getEventCreator().createInstance(null));
+	public void unknownPayload() {
+		Event event = GsonUtils.fromJson(
+				"{\"type\":\"NotAnEventType\",\"payload\":{}}", Event.class);
+		assertNotNull(event);
+		assertNotNull(event.getPayload());
+		assertEquals(EventPayload.class, event.getPayload().getClass());
 	}
 
 	/**
-	 * Unknown event payload returned as EventPayload
+	 * Event with missing type has payload returned as {@link EventPayload}
 	 */
 	@Test
-	public void unknownPayload() {
-		EventFormatter formatter = new EventFormatter();
-		formatter.getEventCreator().createInstance(null);
-		EventPayload payload = formatter.getPayloadDeserializer().deserialize(null, null, null);
-		assertTrue(payload instanceof EventPayload);
+	public void missingType() {
+		Event event = GsonUtils.fromJson("{\"payload\":{}}", Event.class);
+		assertNotNull(event);
+		assertNotNull(event.getPayload());
+		assertEquals(EventPayload.class, event.getPayload().getClass());
+	}
+
+	/**
+	 * Missing payload
+	 */
+	@Test
+	public void missingPayload() {
+		Event event = GsonUtils.fromJson("{}", Event.class);
+		assertNotNull(event);
+		assertNull(event.getPayload());
 	}
 }