}

    // Demonstrates observed equals() asymmetry when this is shorter than argument
    @Test
    @DisplayName("equals: this shorter but same prefix -> true (observed behavior)")
    void equals_thisShorterSamePrefix_true_dueToImplementation() {
        // Arrange: left shorter than right but with identical prefix

   * A word about using {@link Equivalence}, which automatically checks for {@code null} and
   * identical inputs: This sounds like it ought to be a problem here, since the goals of this class
   * include testing that {@code equals()} is reflexive and is tolerant of {@code null}. However,
   * there's no problem. The reason: {@link EqualsTester} tests {@code null} and identical inputs
   * directly against {@code equals()} rather than through the {@code Equivalence}.

    }

    /**
     * Finish building an instance which also maps {@code x = x2} to {@code y = y2}. These values
     * must not both be identical to the values given in the first mapping. If only the {@code x}
     * values are identical, the transformation is vertical. If only the {@code y} values are
     * identical, the transformation is horizontal (i.e. the slope is zero).
     */
    public LinearTransformation and(double x2, double y2) {

    assertEquals("a", Strings.commonPrefix("abc", "aaaaa"));
    assertEquals("aa", Strings.commonPrefix("aa", "aaaaa"));
    assertEquals("abc", Strings.commonPrefix(new StringBuilder("abcdef"), "abcxyz"));

    // Identical valid surrogate pairs.
    assertEquals(
        "abc\uD8AB\uDCAB", Strings.commonPrefix("abc\uD8AB\uDCABdef", "abc\uD8AB\uDCABxyz"));
    // Differing valid surrogate pairs.

   * A word about using {@link Equivalence}, which automatically checks for {@code null} and
   * identical inputs: This sounds like it ought to be a problem here, since the goals of this class
   * include testing that {@code equals()} is reflexive and is tolerant of {@code null}. However,
   * there's no problem. The reason: {@link EqualsTester} tests {@code null} and identical inputs
   * directly against {@code equals()} rather than through the {@code Equivalence}.

            assertArrayEquals(firstEncoding, secondEncoding, "First and second encoding should be identical");
            assertArrayEquals(secondEncoding, thirdEncoding, "Second and third encoding should be identical");

            // Verify content preservation
            assertArrayEquals(mechs, parsed2.getMechanisms());
            assertEquals(flags, parsed2.getContextFlags());

import java.util.Collection;
import java.util.Set;
import org.jspecify.annotations.NullUnmarked;

/**
 * Variant of {@link SerializableTester} that does not require the reserialized object's class to be
 * identical to the original.
 *
 * @author Chris Povirk
 */
/*
 * The whole thing is really @GwtIncompatible, but GwtJUnitConvertedTestModule doesn't have a

/// tip

         * ours. Therefore, we have to be careful about whether we create our own TypeVariable:
         *
         * 2a. If the resolved types are identical to the original types, then we can return the
         * original, identical JDK TypeVariable. By doing so, we sidestep the problem entirely.
         *
         * 2b. If the resolved types are different from the original types, things are trickier. The

    Object[] array = collection.toArray();
    expectArrayContentsAnyOrder(createSamplesArray(), array);
  }

  /**
   * {@link Collection#toArray(Object[])} says: "Note that {@code toArray(new Object[0])} is
   * identical in function to {@code toArray()}."
   *
   * <p>For maximum effect, the collection under test should be created from an element array of a
   * type other than {@code Object[]}.
   */