Match BaseEvent entities API with Android tracker

Sources/Snowplow/Events/EventBase.swift

@@ -82,18 +82,18 @@ public class Event: NSObject {
  return self
  }
 
- /// Replace the context entities attached to the event with a new list of entities.
+ /// Adds a list of context entities to the existing ones.
  @objc
  public func entities(_ entities: [SelfDescribingJson]) -> Self {
- self.entities = entities
+ self.entities.append(contentsOf: entities)
  return self
  }
 
- /// Replace the context entities attached to the event with a new list of entities.
+ /// Adds a list of context entities to the existing ones.
  @objc
  @available(*, deprecated, renamed: "entities")
  public func contexts(_ entities: [SelfDescribingJson]) -> Self {
- self.entities = entities
+ self.entities.append(contentsOf: entities)
  return self
  }
 }

Tests/TestEvents.swift

@@ -24,6 +24,27 @@ class TestEvents: XCTestCase {
  event.trueTimestamp = testDate
  XCTAssertEqual(event.trueTimestamp, testDate)
  }
+
+ func testEntities() {
+ let event = ScreenView(name: "screen")
+ let entity1 = SelfDescribingJson(schema: "schema1", andData: [String:NSObject]())
+ let entity2 = SelfDescribingJson(schema: "schema2", andData: [String:NSObject]())
+ let entity3 = SelfDescribingJson(schema: "schema3", andData: [String:NSObject]())
+
+ event.entities.append(entity1)
+ XCTAssertEqual(1, event.entities.count)
+
+ _ = event.entities([entity2])
+ XCTAssertEqual(2, event.entities.count)
+
+ _ = event.contexts([entity3])
+ XCTAssertEqual(3, event.entities.count)
+
+ XCTAssertEqual(3, event.contexts.count)
+ XCTAssertTrue(event.entities.contains(entity1))
+ XCTAssertTrue(event.entities.contains(entity2))
+ XCTAssertTrue(event.entities.contains(entity3))
+ }
 
  func testApplicationInstall() {
  // Prepare ApplicationInstall event