code: @Test public void shouldBuildValidInjectorWithFewFieldsSet() throws Exception {
    final NamingStrategy mockNamingStrategy=mock(NamingStrategy.class);
    final ProcessorsFactory mockProcessorsFactory=mock(ProcessorsFactory.class);
    final UriLocatorFactory mockLocatorFactory=mock(UriLocatorFactory.class);
    final MetaDataFactory mockMetaDataFactory=Mockito.mock(MetaDataFactory.class);
    final BaseWroManagerFactory managerFactroy=new BaseWroManagerFactory();
    managerFactroy.setNamingStrategy(mockNamingStrategy);
    managerFactroy.setProcessorsFactory(mockProcessorsFactory);
    managerFactroy.setUriLocatorFactory(mockLocatorFactory);
    managerFactroy.setMetaDataFactory(mockMetaDataFactory);
    final Injector injector=InjectorBuilder.create(managerFactroy).build();
    assertNotNull(injector);
    final Sample sample=new Sample();
    injector.inject(sample);
    assertNotNull(sample.preProcessorExecutor);
    sample.namingStrategy.rename("",WroUtil.EMPTY_STREAM);
    verify(mockNamingStrategy).rename("",WroUtil.EMPTY_STREAM);
    sample.processorsFactory.getPostProcessors();
    verify(mockProcessorsFactory).getPostProcessors();
    sample.uriLocatorFactory.getInstance("");
    verify(mockLocatorFactory).getInstance("");
    sample.metaDataFactory.create();
    verify(mockMetaDataFactory).create();
    assertNotNull(sample.callbackRegistry);
    assertSame(injector,sample.injector);
    assertNotNull(sample.groupsProcessor);
    assertNotNull(sample.modelFactory);
    assertNotNull(sample.groupExtractor);
    assertNotNull(sample.cacheStrategy);
    assertNotNull(sample.hashBuilder);
    assertNotNull(sample.readOnlyContext);
    assertNotNull(sample.metaDataFactory);
    assertNotNull(sample.cacheKeyFactory);
    assertNotNull(sample.bundleProcessor);
  }
  