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

/**
 * Unit tests for the {@link ModelVersionUtils} utility class.
 * Tests model version detection, validation, upgrade logic, and namespace operations.
 */
@DisplayName("ModelVersionUtils")
class ModelVersionUtilsTest {

    @Nested

import java.io.IOException;
import java.io.Reader;
import java.io.Writer;
import java.nio.CharBuffer;
import java.util.ArrayList;
import java.util.List;
import org.jspecify.annotations.Nullable;

/**
 * Provides utility methods for working with character streams.
 *
 * @author Chris Nokleberg
 * @author Bin Zhu
 * @author Colin Decker
 * @since 1.0
 */
@J2ktIncompatible
@GwtIncompatible
public final class CharStreams {

import com.google.common.annotations.J2ktIncompatible;
import java.io.Serializable;
import java.util.Map;
import java.util.Objects;
import org.jspecify.annotations.Nullable;

/**
 * Static utility methods pertaining to {@code com.google.common.base.Function} instances; see that
 * class for information about migrating to {@code java.util.function}.
 *

## Pydantic `Settings` { #pydantic-settings }

Fortunately, Pydantic provides a great utility to handle these settings coming from environment variables with <a href="https://docs.pydantic.dev/latest/concepts/pydantic_settings/" class="external-link" target="_blank">Pydantic: Settings management</a>.

import com.google.common.annotations.GwtCompatible;
import com.google.errorprone.annotations.CanIgnoreReturnValue;
import java.util.Arrays;
import java.util.Comparator;

/**
 * Static utility methods pertaining to {@code int} primitives that interpret values as
 * <i>unsigned</i> (that is, any negative value {@code x} is treated as the positive value {@code

import java.util.concurrent.PriorityBlockingQueue;
import java.util.concurrent.SynchronousQueue;
import java.util.concurrent.TimeUnit;
import org.jspecify.annotations.Nullable;

/**
 * Static utility methods pertaining to {@link Queue} and {@link Deque} instances. Also see this
 * class's counterparts {@link Lists}, {@link Sets}, and {@link Maps}.
 *
 * @author Kurt Alfred Kluever
 * @since 11.0
 */
@GwtCompatible

         * Class argument that this test uses. Normally we'd fix that by declaring a
         * ReflectionFreeAssertThrowsTest with a testNulls method, but that's annoying to have to do
         * for a package-private utility class. So we skip the class entirely instead.
         */
        continue;
      }
      try {
        tester.doTestNulls(classToTest, visibility);
      } catch (Throwable e) {

import java.lang.reflect.Method;
import java.util.AbstractList;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import org.jspecify.annotations.Nullable;

/**
 * Static utility methods pertaining to instances of {@link Throwable}.
 *
 * <p>See the Guava User Guide entry on <a
 * href="https://github.com/google/guava/wiki/ThrowablesExplained">Throwables</a>.
 *
 * @author Kevin Bourrillion

import com.google.common.annotations.GwtCompatible;
import com.google.errorprone.annotations.CanIgnoreReturnValue;
import java.math.BigInteger;
import java.util.Arrays;
import java.util.Comparator;

/**
 * Static utility methods pertaining to {@code long} primitives that interpret values as
 * <i>unsigned</i> (that is, any negative value {@code x} is treated as the positive value {@code

         * Class argument that this test uses. Normally we'd fix that by declaring a
         * ReflectionFreeAssertThrowsTest with a testNulls method, but that's annoying to have to do
         * for a package-private utility class. So we skip the class entirely instead.
         */
        continue;
      }
      try {
        tester.doTestNulls(classToTest, visibility);
      } catch (Throwable e) {