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How to use ShouldHaveRootCauseInstance class of org.assertj.core.error package

Best Assertj code snippet using org.assertj.core.error.ShouldHaveRootCauseInstance

Source:Throwables_assertHasRootCauseInstanceOf_Test.java

...12 */13package org.assertj.core.internal.throwables;14import org.assertj.core.api.AssertionInfo;15import org.assertj.core.api.Assertions;16import org.assertj.core.error.ShouldHaveRootCauseInstance;17import org.assertj.core.internal.ThrowablesBaseTest;18import org.assertj.core.test.TestData;19import org.assertj.core.test.TestFailures;20import org.assertj.core.util.FailureMessages;21import org.junit.jupiter.api.Test;22import org.mockito.Mockito;23/**24 * Tests for25 * {@link org.assertj.core.internal.Throwables#assertHasRootCauseInstanceOf(org.assertj.core.api.AssertionInfo, Throwable, Class)}26 * .27 *28 * @author Jean-Christophe Gay29 */30public class Throwables_assertHasRootCauseInstanceOf_Test extends ThrowablesBaseTest {31    private Throwable throwableWithCause = new Throwable(new Exception(new IllegalArgumentException()));32    @Test33    public void should_pass_if_root_cause_is_exactly_instance_of_expected_type() {34        throwables.assertHasRootCauseInstanceOf(TestData.someInfo(), throwableWithCause, IllegalArgumentException.class);35    }36    @Test37    public void should_pass_if_root_cause_is_instance_of_expected_type() {38        throwables.assertHasRootCauseInstanceOf(TestData.someInfo(), throwableWithCause, RuntimeException.class);39    }40    @Test41    public void should_fail_if_actual_is_null() {42        Assertions.assertThatExceptionOfType(AssertionError.class).isThrownBy(() -> throwables.assertHasRootCauseInstanceOf(someInfo(), null, .class)).withMessage(FailureMessages.actualIsNull());43    }44    @Test45    public void should_throw_NullPointerException_if_given_type_is_null() {46        Assertions.assertThatNullPointerException().isThrownBy(() -> throwables.assertHasRootCauseInstanceOf(someInfo(), throwableWithCause, null)).withMessage("The given type should not be null");47    }48    @Test49    public void should_fail_if_actual_has_no_cause() {50        AssertionInfo info = TestData.someInfo();51        Class<NullPointerException> expectedCauseType = NullPointerException.class;52        try {53            throwables.assertHasRootCauseInstanceOf(info, ThrowablesBaseTest.actual, expectedCauseType);54        } catch (AssertionError err) {55            Mockito.verify(failures).failure(info, ShouldHaveRootCauseInstance.shouldHaveRootCauseInstance(ThrowablesBaseTest.actual, expectedCauseType));56            return;57        }58        TestFailures.failBecauseExpectedAssertionErrorWasNotThrown();59    }60    @Test61    public void should_fail_if_root_cause_is_not_instance_of_expected_type() {62        AssertionInfo info = TestData.someInfo();63        Class<NullPointerException> expectedCauseType = NullPointerException.class;64        try {65            throwables.assertHasRootCauseInstanceOf(info, throwableWithCause, expectedCauseType);66        } catch (AssertionError err) {67            Mockito.verify(failures).failure(info, ShouldHaveRootCauseInstance.shouldHaveRootCauseInstance(throwableWithCause, expectedCauseType));68            return;69        }70        TestFailures.failBecauseExpectedAssertionErrorWasNotThrown();71    }72}...

ShouldHaveRootCauseInstance

Using AI Code Generation

1public class ShouldHaveRootCauseInstance extends BasicErrorMessageFactory {2  private static final String SHOULD_HAVE_ROOT_CAUSE_INSTANCE = "%nExpecting root cause of%n  <%s>%nto be an instance of:%n  <%s>%nbut was an instance of:%n  <%s>.";3  public ShouldHaveRootCauseInstance(Throwable actual, Class<? extends Throwable> expectedType) {4    super(SHOULD_HAVE_ROOT_CAUSE_INSTANCE, actual, expectedType, actual.getCause().getClass());5  }6}7public void test_should_have_root_cause_instance() {8  Throwable actual = new Throwable(new IllegalArgumentException("argument is null"));9  ErrorMessageFactory factory = shouldHaveRootCauseInstance(actual, NullPointerException.class);10  String message = factory.create(new TextDescription("Test"), new StandardRepresentation());11  Assertions.assertThat(message).isEqualTo(String.format(12    "[Test] %nExpecting root cause of%n  <java.lang.Throwable: java.lang.IllegalArgumentException: argument is null>%nto be an instance of:%n  <java.lang.NullPointerException>%nbut was an instance of:%n  <java.lang.IllegalArgumentException>"));13}

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