Add equality functions for SelfDescribing and SelfDescribingJson so t…

…hat they can be compared in unit tests (close  #380)

PR #381

src/main/java/com/snowplowanalytics/snowplow/tracker/events/SelfDescribing.java

@@ -95,4 +95,22 @@ public TrackerPayload getPayload() {
                 Parameter.SELF_DESCRIBING_ENCODED, Parameter.SELF_DESCRIBING);
         return putTrueTimestamp(payload);
     }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+
+        SelfDescribing that = (SelfDescribing) o;
+
+        if (base64Encode != that.base64Encode) return false;
+        return Objects.equals(eventData, that.eventData);
+    }
+
+    @Override
+    public int hashCode() {
+        int result = eventData != null ? eventData.hashCode() : 0;
+        result = 31 * result + (base64Encode ? 1 : 0);
+        return result;
+    }
 }

src/main/java/com/snowplowanalytics/snowplow/tracker/payload/SelfDescribingJson.java

@@ -198,4 +198,19 @@ public long getByteSize() {
     public String toString() {
         return Utils.mapToJSONString(payload);
     }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+
+        SelfDescribingJson that = (SelfDescribingJson) o;
+
+        return payload.equals(that.payload);
+    }
+
+    @Override
+    public int hashCode() {
+        return payload.hashCode();
+    }
 }

src/test/java/com/snowplowanalytics/snowplow/tracker/events/SelfDescribingTest.java

@@ -0,0 +1,37 @@
+package com.snowplowanalytics.snowplow.tracker.events;
+
+import com.snowplowanalytics.snowplow.tracker.payload.SelfDescribingJson;
+
+// JUnit
+import org.junit.Test;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotEquals;
+
+public class SelfDescribingTest {
+
+    @Test
+    public void testEqualityOfTwoInstances() {
+        SelfDescribing.Builder<?> builder = SelfDescribing.builder()
+                .eventData(new SelfDescribingJson("schema-name"));
+
+        SelfDescribing a = new SelfDescribing( builder );
+        SelfDescribing b = new SelfDescribing( builder );
+
+        assertEquals(a, b);
+    }
+
+    @Test
+    public void testNegativeEqualityOfTwoInstances() {
+        SelfDescribing.Builder<?> builderOne = SelfDescribing.builder()
+                .eventData(new SelfDescribingJson("schema-name-one"));
+
+        SelfDescribing.Builder<?> builderTwo = SelfDescribing.builder()
+                .eventData(new SelfDescribingJson("schema-name-two"));
+
+        SelfDescribing a = new SelfDescribing( builderOne );
+        SelfDescribing b = new SelfDescribing( builderTwo );
+
+        assertNotEquals(a, b);
+    }
+
+}

src/test/java/com/snowplowanalytics/snowplow/tracker/payload/SelfDescribingJsonTest.java

@@ -20,6 +20,9 @@
 import org.junit.Test;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertNotEquals;
+
+
 
 public class SelfDescribingJsonTest {
 
@@ -67,4 +70,64 @@ public void testMakeSdjWithSdj() {
         assertNotNull(sdj);
         assertEquals(expected, sdjString);
     }
+
+    @Test
+    public void testEqualityOfTwoInstances_withSchemaNameOnly() {
+        SelfDescribingJson a = new SelfDescribingJson("schema");
+        SelfDescribingJson b = new SelfDescribingJson("schema");
+        assertEquals(a, b);
+    }
+
+    @Test
+    public void testEqualityOfTwoInstances_withTrackerPayload() {
+        TrackerPayload nestedData = new TrackerPayload();
+        nestedData.add("key", "value");
+        SelfDescribingJson a = new SelfDescribingJson("schema", nestedData);
+        SelfDescribingJson b = new SelfDescribingJson("schema", nestedData);
+        assertEquals(a, b);
+    }
+
+    @Test
+    public void testEqualityOfTwoInstances_withNestedEvent() {
+        TrackerPayload nestedData = new TrackerPayload();
+        nestedData.add("key", "value");
+        SelfDescribingJson nestedEvent = new SelfDescribingJson("nested_event", nestedData);
+        SelfDescribingJson a = new SelfDescribingJson("schema", nestedEvent);
+        SelfDescribingJson b = new SelfDescribingJson("schema", nestedEvent);
+        assertEquals(a, b);
+    }
+
+    @Test
+    public void testNegativeEqualityOfTwoInstances_withSchemaNameOnly() {
+        SelfDescribingJson a = new SelfDescribingJson("schema-one");
+        SelfDescribingJson b = new SelfDescribingJson("schema-two");
+        assertNotEquals(a, b);
+    }
+
+    @Test
+    public void testNegativeEqualityOfTwoInstances_withTrackerPayload() {
+        TrackerPayload nestedDataOne = new TrackerPayload();
+        nestedDataOne.add("key", "value-one");
+        TrackerPayload nestedDataTwo = new TrackerPayload();
+        nestedDataTwo.add("key", "value-two");
+        SelfDescribingJson a = new SelfDescribingJson("schema", nestedDataOne);
+        SelfDescribingJson b = new SelfDescribingJson("schema", nestedDataTwo);
+        assertNotEquals(a, b);
+    }
+
+    @Test
+    public void testNegativeEqualityOfTwoInstances_withNestedEvent() {
+        TrackerPayload nestedDataOne = new TrackerPayload();
+        nestedDataOne.add("key", "value-one");
+        SelfDescribingJson nestedEventOne = new SelfDescribingJson("nested_event", nestedDataOne);
+
+        TrackerPayload nestedDataTwo = new TrackerPayload();
+        nestedDataTwo.add("key", "value-two");
+        SelfDescribingJson nestedEventTwo = new SelfDescribingJson("nested_event", nestedDataTwo);
+
+
+        SelfDescribingJson a = new SelfDescribingJson("schema", nestedEventOne);
+        SelfDescribingJson b = new SelfDescribingJson("schema", nestedEventTwo);
+        assertNotEquals(a, b);
+    }
 }