A survey on the Spring MVC method test API model (). Attribute ()

Question

I am trying to test the following controller method using the Spring MVC test API:

@RequestMapping(value = "/preference/email", method = RequestMethod.GET, produces = "text/html") public String emailForm(@ModelAttribute EmailInfo emailInfo, Model model, @CurrentMember Member member) { emailInfo.setEmail(member.getEmail()); emailInfo.setActivated(member.isActivated()); emailInfo.setToken(member.getToken()); model.addAttribute("emailInfo", emailInfo); return "preference"; } 

When I debug the following test method ...

 @Test public void shouldPopulateEmailInfo() throws Exception { when(currentMemberHandlerMethodArgumentResolver.supportsParameter(any(MethodParameter.class))).thenReturn(Boolean.TRUE); when(currentMemberHandlerMethodArgumentResolver.resolveArgument(any(MethodParameter.class), any(ModelAndViewContainer.class), any(NativeWebRequest.class), any(WebDataBinderFactory.class))).thenReturn(currentMember); mockMvc.perform(get("/preference/email"))// .andDo(print())// .andExpect(model().attribute("emailInfo.email", " [e-mail] "));// } 

... I see that " [e-mail] " is set in the emailInfo email field .

However, I systematically get:

 java.lang.AssertionError: Model attribute 'emailInfo.email' expected:< [e-mail] > but was:<null> at org.springframework.test.util.AssertionErrors.fail(AssertionErrors.java:60) at org.springframework.test.util.AssertionErrors.assertEquals(AssertionErrors.java:89) at org.springframework.test.web.servlet.result.ModelResultMatchers$2.match(ModelResultMatchers.java:68) at org.springframework.test.web.servlet.MockMvc$1.andExpect(MockMvc.java:141) at com.bignibou.tests.controller.preference.PreferenceControllerEmailManagementTest.shouldPopulateEmailInfo(PreferenceControllerEmailManagementTest.java:109) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:606) at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47) at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12) at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44) at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17) at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26) at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:74) at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:83) at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:72) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:231) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:88) at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238) at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63) at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236) at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53) at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229) at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61) at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:71) at org.junit.runners.ParentRunner.run(ParentRunner.java:309) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:174) at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50) at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197) 

There is something that I cannot get using the Spring Mvc Test API .... Can anyone help?

edit : this is what I came up with after taking into account the provided answer:

 .andExpect(model().attribute("emailInfo", Matchers.hasProperty("email", Matchers.equalTo(" [e-mail] "))));// 

Now it works great.

Answer 1

Model attributes are pairs of value objects. Expression resolution does not occur. When you do

 model().attribute("emailInfo.email", " [e-mail] "));// 

You ask if there is a Model attribute with the emailInfo.email key that has the specified value. The answer is clearly missing, since you do not have such a Model attribute with such a key.

You have

 model.addAttribute("emailInfo", emailInfo); 

which is the Model attribute with the emailInfo key, which contains an object of type emailInfo . You need to compare the email field of the emailInfo object yourself.

Answer 2

As Sotirios noted, model().attribute("attributeName") will not let you navigate, and it will use all of this as a name.

However, you can use this method instead of:

 public <T> ResultMatcher attribute(final String name, final Matcher<T> matcher) 

This will allow you to specify a Hamcrest match to match your attributes as follows:

 .andExpect(model().attribute("emailInfo", hasProperty("email", is(" [e-mail] ")))) 

Just make sure you have the Hamcrest library in your classpath and import it like this:

 import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.* 

Note. For import, it is especially important if you use Groovy for your tests (Spock) as method names in the Hamcrest conflict with the Groovy standard library