import java.io.File

fun Configuration.getSingleFileProvider(): Provider<File> {
    val name = this.name
    return incoming.files.elements.map {
        require(it.size <= 1) {
            "Expected at most one file in configuration '$name' but found: $it"
        }
        it.firstOrNull()?.asFile
    }
}

fun NamedDomainObjectProvider<Configuration>.getSingleFileProvider(): Provider<File> {

    List<E> iteratorElements = new ArrayList<>();
    for (E element : collection) { // uses iterator()
      iteratorElements.add(element);
    }
    List<E> expected = copyToList(getOrderedElements());
    assertEquals("Different ordered iteration", expected, iteratorElements);
  }

  @CollectionFeature.Require(ALLOWS_NULL_VALUES)
  @CollectionSize.Require(absent = ZERO)
  public void testIterator_nullElement() {

     */
    public void testCreateCustomFilter_NullPatterns() {
        try {
            SerializeUtil.createCustomFilter(null);
            fail("Expected IllegalArgumentException");
        } catch (final IllegalArgumentException e) {
            // Expected
        }
    }

    /**
     * Test serialization with empty array
     *
     * @throws Exception
     */

    assertTrue(
        from.getType() + " is expected to be assignable to " + to.getType(),
        to.isSupertypeOf(from));
    assertTrue(
        to.getType() + " is expected to be a supertype of " + from.getType(),
        to.isSupertypeOf(from));
    assertTrue(
        from.getType() + " is expected to be a subtype of " + to.getType(), from.isSubtypeOf(to));
  }

    assertBitEquals(1.0, at.get());
    for (double x : VALUES) {
      at.lazySet(x);
      assertBitEquals(x, at.get());
    }
  }

  /** compareAndSet succeeds in changing value if equal to expected else fails */
  public void testCompareAndSet() {
    double prev = Math.E;
    double unused = Math.E + Math.PI;
    AtomicDouble at = new AtomicDouble(prev);
    for (double x : VALUES) {

  public void testFailsToForward() {
    try {
      ForwardingObjectTester.testForwardingObject(FailToForward.class);
    } catch (AssertionError | UnsupportedOperationException expected) {
      // UnsupportedOperationException is what we see on Android.
      return;
    }
    fail("Should have thrown");
  }

import com.google.common.annotations.J2ktIncompatible;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

/**
 * Tests that {@link AggregateFutureState} uses the expected {@code AtomicHelper} implementation.
 *
 * <p>We have more thorough testing of {@code AtomicHelper} implementations in {@link
 * AggregateFutureStateFallbackAtomicHelperTest}. The advantage to this test is that it can run

public class CollectionStreamTester<E> extends AbstractCollectionTester<E> {
  /*
   * We're not really testing the implementation of Stream, only that we're getting a Stream
   * that corresponds to the expected elements.
   */

  @CollectionFeature.Require(absent = KNOWN_ORDER)
  public void testStreamToArrayUnknownOrder() {
    Helpers.assertEqualIgnoringOrder(getSampleElements(), asList(collection.stream().toArray()));
  }

        val peekedHeader =
          reader.peekHeader()
            ?: throw ProtocolException("expected a value at $reader")

        val choice =
          choices.firstOrNull { it.matches(peekedHeader) }
            ?: throw ProtocolException(
              "expected a matching choice but was $peekedHeader at $reader",
            )

        return choice to choice.fromDer(reader)
      }

                if (logger.isDebugEnabled()) {
                    logger.warn("Failed to parse max_access_count: '{}'. Expected: integer value", maxAccessCount, e);
                } else {
                    logger.warn("Failed to parse max_access_count: '{}'. Expected: integer value", maxAccessCount);
                }
            }
        }