Multiple assertions

When checking for multiple elements, chaining assertions is cleaner than multiple separate assertTrue() calls.

Before

AssertListContains.java

import org.junit.jupiter.api.Test;

import java.util.List;

import static org.junit.jupiter.api.Assertions.assertTrue;

class AssertListContains {

    List<String> list = List.of("a", "b", "c");

    @Test
    void assertMultipleElements() {
        assertTrue(list.contains("a"));
        assertTrue(list.contains("b"));
        assertTrue(list.contains("c"));
    }
}

warning

Multiple assertTrue() calls are verbose and stop at the first failure, hiding subsequent issues.

After

AssertListContains.java

import org.junit.jupiter.api.Test;

import java.util.List;

import static org.assertj.core.api.Assertions.assertThat;

class AssertListContains {

    List<String> list = List.of("a", "b", "c");

    @Test
    void assertMultipleElements() {
        assertThat(list).contains("a", "b", "c");
    }
}

tip

AssertJ allows checking for multiple elements in a single assertion, making the test more concise and showing all missing elements in case of failure.