add SlackEventMessageDeserializationTest

slack-base/src/test/java/com/hubspot/slack/client/models/events/includingfiles/SlackEventMessageDeserializationTest.java

@@ -0,0 +1,36 @@
+package com.hubspot.slack.client.models.events.includingfiles;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import com.fasterxml.jackson.core.type.TypeReference;
+import com.hubspot.slack.client.jackson.ObjectMapperUtils;
+import com.hubspot.slack.client.models.JsonLoader;
+import com.hubspot.slack.client.models.events.SlackEventType;
+import com.hubspot.slack.client.models.events.SlackEventWrapper;
+import java.io.IOException;
+import org.junit.Test;
+
+public class SlackEventMessageDeserializationTest {
+
+  @Test
+  public void itDeserializes() throws IOException {
+    SlackEventMessage slackEvent = fetchAndDeserializeSlackEvent(
+      "message_shared_with_file.json"
+    );
+    assertThat(slackEvent.getType()).isEqualTo(SlackEventType.MESSAGE);
+    assertThat(slackEvent.getFiles().size()).isEqualTo(2);
+  }
+
+  private SlackEventMessage fetchAndDeserializeSlackEvent(String jsonFileName)
+    throws IOException {
+    String rawJson = JsonLoader.loadJsonFromFile(jsonFileName);
+    return deserializeSlackEvent(rawJson);
+  }
+
+  private SlackEventMessage deserializeSlackEvent(String rawJson) throws IOException {
+    SlackEventWrapper<SlackEventMessage> eventWrapper = ObjectMapperUtils
+      .mapper()
+      .readValue(rawJson, new TypeReference<>() {});
+    return eventWrapper.getEvent();
+  }
+}