JUnit assertion can be 'assertThat()' call

Reports calls to Assert.assertEquals(), Assert.assertTrue(), etc. methods which can be migrated to Hamcrest declarative style Assert.assertThat() calls.

For example:

public class SubstantialTest {
  @Test
  public void testContents(Collection<String> c, String s) {
    Assert.assertTrue(c.contains(s));
    Assert.assertEquals(c, s);
    Assert.assertNotNull(c);
    Assert.assertNull(c);
    Assert.assertFalse(c.contains(s));
  }
}

A quick-fix is provided to perform the migration:

public class SubstantialTest {
  @Test
  public void testContents(Collection<String> c, String s) {
    assertThat(c, hasItem(o));
    assertThat(o, is(c));
    assertThat(c, notNullValue());
    assertThat(c, nullValue());
    assertThat(c, not(hasItem(o)));
  }
}

This inspection requires that the Hamcrest library is available on the classpath.

Use the Statically import matcher's methods option to specify if you want the quick-fix to statically import the Hamcrest matcher methods.

Inspection options

Option	Type	Default
Statically import matcher's methods	Checkbox	true

Inspection Details
Available in:	IntelliJ IDEA 2023.3, Qodana for JVM 2023.3
Plugin:	Java, 233.SNAPSHOT

Last modified: 13 July 2023