) {
      check(!closed) { "closed" }
      checkOffsetAndCount(source.size, 0, byteCount)
      socket.sink.write(source, byteCount)
    }

    override fun flush() {
      if (closed) return // Don't throw; this stream might have been closed on the caller's behalf.
      socket.sink.flush()
    }

    override fun close() {
      if (closed) return
      closed = true
      detachTimeout(timeout)

  }

  /*
   * Whenever an implementation uses `instanceof` on a parameter instance, the test has to know that
   * (so much for "black box") and try instances that both do and don't pass the check. The "don't"
   * half of that is more awkward to arrange...
   */
  private static <T> Iterable<T> iterable(Collection<T> collection) {
    // return collection::iterator;
    return new Iterable<T>() {

      // It is possible due to races that we are currently in the expected state even though we
      // timed out. e.g. if we weren't event able to grab the lock within the timeout we would never
      // even check the guard. I don't think we care too much about this use case but it could lead
      // to a confusing error message.
      throw new TimeoutException("Timed out waiting for " + this + " to reach the RUNNING state.");
    }
  }

 *
 * @author Anthony Zana
 */
@NullUnmarked
public class UninterruptiblesTest extends TestCase {
  private static final String EXPECTED_TAKE = "expectedTake";

  /** Timeout to use when we don't expect the timeout to expire. */
  private static final long LONG_DELAY_MS = 2500;

  private static final long SLEEP_SLACK = 2;

  private final TearDownStack tearDownStack = new TearDownStack();

  }

  private static long random() {
    return randomSource.nextLong();
  }

  // A random value that cannot be 0 and that is unsigned-less-than or equal
  // to the given dividend, so that we don't have half of our divisions being
  // trivial because the divisor is bigger than the dividend.
  // Using remainder here does not give us a uniform distribution but it should
  // not have a big impact on the measurement.

        };

        // Test each pattern and see what actually works
        for (String cron : potentiallyValidCrons) {
            boolean result = validator.isValid(cron, context);
            // Don't assert true/false here, just test that method doesn't throw
            assertNotNull("Validation should return a boolean result for: " + cron, Boolean.valueOf(result));
        }
    }

  static final String NOT_AVAILABLE_ON_UNDIRECTED =
      "Cannot call source()/target() on a EndpointPair from an undirected graph. Consider calling "
          + "adjacentNode(node) if you already have a node, or nodeU()/nodeV() if you don't.";
  static final String EDGE_ALREADY_EXISTS = "Edge %s already exists in the graph.";
  static final String ENDPOINTS_MISMATCH =
      "Mismatch: endpoints' ordering is not compatible with directionality of the graph";

# Dependencies in path operation decorators { #dependencies-in-path-operation-decorators }

In some cases you don't really need the return value of a dependency inside your *path operation function*.

Or the dependency doesn't return a value.

But you still need it to be executed/solved.

For those cases, instead of declaring a *path operation function* parameter with `Depends`, you can add a `list` of `dependencies` to the *path operation decorator*.

                            }
                        } catch (ResourceDoesNotExistException md5TryException) {
                            // this was a failed transfer, and we don't want to retry.
                            handleChecksumFailure(
                                    checksumPolicy,
                                    "Error retrieving checksum file for " + remotePath,

Using `check_same_thread=False` allows FastAPI to use the same SQLite database in different threads. This is necessary as **one single request** could use **more than one thread** (for example in dependencies).

Don't worry, with the way the code is structured, we'll make sure we use **a single SQLModel *session* per request** later, this is actually what the `check_same_thread` is trying to achieve.

### Create the Tables { #create-the-tables }