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

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

Source:OptionalAssert_containsInstanceOf_Test.java

...14import java.util.Optional;15import org.assertj.core.api.Assertions;16import org.assertj.core.api.BaseTest;17import org.assertj.core.error.OptionalShouldBePresent;18import org.assertj.core.error.OptionalShouldContainInstanceOf;19import org.junit.jupiter.api.Test;20public class OptionalAssert_containsInstanceOf_Test extends BaseTest {21    @Test22    public void should_fail_if_optional_is_empty() {23        Optional<Object> actual = Optional.empty();24        Throwable thrown = Assertions.catchThrowable(() -> {25            assertThat(actual).containsInstanceOf(.class);26        });27        Assertions.assertThat(thrown).isInstanceOf(AssertionError.class).hasMessage(OptionalShouldBePresent.shouldBePresent(actual).create());28    }29    @Test30    public void should_pass_if_optional_contains_required_type() {31        Assertions.assertThat(Optional.of("something")).containsInstanceOf(String.class).containsInstanceOf(Object.class);32    }33    @Test34    public void should_pass_if_optional_contains_required_type_subclass() {35        Assertions.assertThat(Optional.of(new OptionalAssert_containsInstanceOf_Test.SubClass())).containsInstanceOf(OptionalAssert_containsInstanceOf_Test.ParentClass.class);36    }37    @Test38    public void should_fail_if_optional_contains_other_type_than_required() {39        Optional<OptionalAssert_containsInstanceOf_Test.ParentClass> actual = Optional.of(new OptionalAssert_containsInstanceOf_Test.ParentClass());40        Throwable thrown = Assertions.catchThrowable(() -> {41            assertThat(actual).containsInstanceOf(.class);42        });43        Assertions.assertThat(thrown).isInstanceOf(AssertionError.class).hasMessage(OptionalShouldContainInstanceOf.shouldContainInstanceOf(actual, OptionalAssert_containsInstanceOf_Test.OtherClass.class).create());44    }45    private static class ParentClass {}46    private static class SubClass extends OptionalAssert_containsInstanceOf_Test.ParentClass {}47    private static class OtherClass {}48}...

Source:OptionalShouldContainInstanceOf.java

...17 * Build an error message when a value should be instance of a specific class.18 *19 * @author Alban Dericbourg20 */21public class OptionalShouldContainInstanceOf extends BasicErrorMessageFactory {22  private OptionalShouldContainInstanceOf(String message) {23    super(message);24  }25  /**26   * Indicates that a value should be present in an empty {@link java.util.Optional}.27   *28   * @param value Optional to be checked.29   * @param clazz the class to check the optional value against30   * @return an error message factory.31   * @throws java.lang.NullPointerException if optional is null.32   */33  public static OptionalShouldContainInstanceOf shouldContainInstanceOf(Object value, Class<?> clazz) {34    Optional<?> optional = (Optional<?>) value;35    if (optional.isPresent()) {36      return new OptionalShouldContainInstanceOf(format("%nExpecting actual:%n %s%nto contain a value that is an instance of:%n %s%nbut did contain an instance of:%n %s",37                                                        optional.getClass().getSimpleName(), clazz.getName(),38                                                        optional.get().getClass().getName()));39    }40    return new OptionalShouldContainInstanceOf(format("%nExpecting actual:%n %s%nto contain a value that is an instance of:%n %s%nbut was empty",41                                                      optional.getClass().getSimpleName(), clazz.getName()));42  }43}...

Source:OptionalShouldContainInstanceOf_create_Test.java

...13package org.assertj.core.error;14import java.util.Optional;15import org.assertj.core.api.Assertions;16import org.junit.jupiter.api.Test;17public class OptionalShouldContainInstanceOf_create_Test {18    @Test19    public void should_create_error_message_with_empty() {20        String errorMessage = OptionalShouldContainInstanceOf.shouldContainInstanceOf(Optional.empty(), Object.class).create();21        Assertions.assertThat(errorMessage).isEqualTo(String.format(("%nExpecting:%n <Optional>%n" + ("to contain a value that is an instance of:%n <java.lang.Object>%n" + "but was empty"))));22    }23    @Test24    public void should_create_error_message_with_expected_type() {25        String errorMessage = OptionalShouldContainInstanceOf.shouldContainInstanceOf(Optional.of(Integer.MIN_VALUE), String.class).create();26        Assertions.assertThat(errorMessage).isEqualTo(String.format(("%nExpecting:%n <Optional>%n" + ("to contain a value that is an instance of:%n <java.lang.String>%n" + "but did contain an instance of:%n <java.lang.Integer>"))));27    }28}...