title: A simple unit test, when run it, get error "No tests found"
body: <p>In my springboot project, I don't need to unit test those mvc things but some pure POJO classes. </p>
  
  <p>My pojo class:</p>
  
  <pre><code>public class Calculator {
  
     public int add(int a, int b) {
         return a+b;
     }
  }
  </code></pre>
  
  <p>My test class:</p>
  
  <pre><code>@ExtendWith(SpringExtension.class)
  public class SimpleTest {
      @Test
      void testIt() {
        Calculator cal = new Calculator();
        int result = cal.add(1, 2);
        assertThat(result).isEqualTo(3);
      }
  }
  </code></pre>
  
  <p>I am using intellij IDE. Next to the <code>void testIt()</code> line of code on the left, there is a small run arrow, when I click and run the test function , I get failure:  </p>
  
  <pre><code>FAILURE: Build failed with an exception.
  * What went wrong:
  Execution failed for task ':test'.
  &gt; No tests found for given includes: [com.my.calculator.SimpleTest.testIt](filter.includeTestsMatching)
  </code></pre>
  
  <p>Why I get this <code>No test found</code> error?</p>
  
  <p>BTW, the dependencies of my project for the test :</p>
  
  <pre><code>testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.3.1'
  testImplementation 'org.junit.jupiter:junit-jupiter-api:5.3.1'
  testImplementation 'org.springframework.boot:spring-boot-starter-test'
  testImplementation 'org.assertj:assertj-core'
  </code></pre>