test(ZNTA-2297): transunithistory returns bad request on null localei…

…d or transunitid

server/services/src/main/java/org/zanata/rest/editor/service/TransUnitHistoryService.java

@@ -66,4 +66,14 @@ public Response get(String localeId, Long transUnitId) {
                 historyHandler.getTranslationHistory(localeId, transUnitId);
         return Response.ok(result).build();
     }
+
+    public TransUnitHistoryService() {
+    }
+
+    @java.beans.ConstructorProperties({"historyHandler"})
+    protected TransUnitHistoryService(
+            final GetTranslationHistoryHandler historyHandler
+    ) {
+        this.historyHandler = historyHandler;
+    }
 }

server/services/src/test/java/org/zanata/rest/editor/service/TransUnitHistoryServiceTest.java

@@ -0,0 +1,39 @@
+package org.zanata.rest.editor.service;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import org.zanata.webtrans.server.rpc.GetTranslationHistoryHandler;
+import org.zanata.webtrans.shared.rpc.GetTranslationHistoryResult;
+
+import javax.ws.rs.core.Response;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class TransUnitHistoryServiceTest {
+    private TransUnitHistoryService service;
+    @Mock
+    private GetTranslationHistoryHandler historyHandler;
+
+    @Before
+    public void setUp() throws Exception {
+        MockitoAnnotations.initMocks(this);
+        historyHandler = new GetTranslationHistoryHandler();
+        service = new TransUnitHistoryService(historyHandler);
+    }
+
+    @Test
+    public void nullOrEmptyLocaleWillReturnBadRequest() {
+        Long transUnitID = 1L;
+        Response response = service.get(null, transUnitID);
+        assertThat(response.getStatus()).isEqualTo(400);
+    }
+
+    @Test
+    public void nullTransUnitIdWillReturnBadRequest() {
+        String localeId = "ja";
+        Response response = service.get(localeId, null);
+        assertThat(response.getStatus()).isEqualTo(400);
+    }
+}