Restore original behaviour

snowplow-tracker/src/androidTest/java/com/snowplowanalytics/snowplow/event/AbstractEventTest.kt

@@ -24,14 +24,21 @@ class AbstractEventTest {
     @Test
     fun testAddsEntitiesUsingAllAPIs() {
         val event = ScreenView("screen")
-        val entity = SelfDescribingJson("schema3", "data3")
-
-        event.entities.add(SelfDescribingJson("schema1", "data1"))
-        event.contexts(listOf(SelfDescribingJson("schema2", "data2")))
-        event.entities(listOf(entity))
+        val entity1 = SelfDescribingJson("schema1", "data1")
+        val entity2 = SelfDescribingJson("schema2", "data2")
+        val entity3 = SelfDescribingJson("schema3", "data3")
 
+        event.entities.add(entity1)
         Assert.assertEquals(1, event.entities.count())
-        Assert.assertEquals(1, event.contexts.count())
-        Assert.assertTrue(event.entities.contains(entity))
+
+        event.entities(listOf(entity2))
+        Assert.assertEquals(2, event.entities.count())
+
+        event.contexts(listOf(entity3))
+        Assert.assertEquals(3, event.entities.count())
+        Assert.assertEquals(3, event.contexts.count())
+        Assert.assertTrue(event.entities.contains(entity1))
+        Assert.assertTrue(event.entities.contains(entity2))
+        Assert.assertTrue(event.entities.contains(entity3))
     }
 }

snowplow-tracker/src/main/java/com/snowplowanalytics/snowplow/event/AbstractEvent.kt

@@ -22,7 +22,7 @@ import java.util.*
  * - "True" timestamp: user-defined custom event timestamp
  */
 abstract class AbstractEvent : Event {
-    private var _entities: MutableList<SelfDescribingJson> = LinkedList()
+    private var _entities = mutableListOf<SelfDescribingJson>()
     /**
      * @return the custom context entities associated with the event.
      */
@@ -55,13 +55,13 @@ abstract class AbstractEvent : Event {
 
     // Builder methods
 
-    /** Replace the context entities attached to the event with a new list of entities. */
+    /** Adds a list of context entities to the existing ones. */
     fun entities(entities: List<SelfDescribingJson>): AbstractEvent {
-        this.entities = entities.toMutableList()
+        this.entities.addAll(entities)
         return this
     }
 
-    /** Replace the context entities attached to the event with a new list of entities. */
+    /** Adds a list of context entities to the existing ones. */
     @Deprecated("Old nomenclature.", ReplaceWith("entities()"))
     fun contexts(contexts: List<SelfDescribingJson>): AbstractEvent {
         return entities(contexts)