*
   * if (guardExpression) {
   *    throw new BadException(badMsg(...));
   * }
   *
   * The alternative natural refactorings into void or Exception-returning methods are much slower.
   * This is a big deal - we're talking factors of 2-8 in microbenchmarks, not just 10-20%. (This is
   * a hotspot optimizer bug, which should be fixed, but that's a separate, big project).
   *

                new ClosingCallable<TestCloseable>() {
                  @Override
                  public TestCloseable call(DeferredCloser closer) throws Exception {
                    closer.eventuallyClose(closeable1, closingExecutor);
                    closer.eventuallyClose(closeable2, closingExecutor);
                    return closeable3;
                  }
                },
                executor)

	}
	// Prefer newest modtime.
	if x.ModTime != o.ModTime {
		return x.ModTime > o.ModTime
	}

	// The following doesn't make too much sense, but we want sort to be consistent nonetheless.
	// Prefer lower types
	if x.Type != o.Type {
		return x.Type < o.Type
	}
	// Consistent sort on signature
	if v := bytes.Compare(x.Signature[:], o.Signature[:]); v != 0 {
		return v > 0
	}
	// On ID mismatch

   * is merely copied. Only as the power set is iterated are the individual subsets created, and
   * these subsets themselves occupy only a small constant amount of memory.
   *
   * @param set the set of elements to construct a power set from
   * @return the power set, as an immutable set of immutable sets

	for k, vv := range req.Header {
		// If request header key is not in ignored headers, then add it.
		if _, ok := ignoredStreamingHeaders[http.CanonicalHeaderKey(k)]; !ok {
			headerMap[strings.ToLower(k)] = vv
		}
	}

	// Get header keys.
	headers := []string{"host"}
	for k := range headerMap {
		headers = append(headers, k)
	}
	sort.Strings(headers)

	// Get canonical headers.

		nsUnlocker = func() { lock.RUnlock(lkctx) }
		unlockOnDefer = true
	}

	checkPrecondFn := opts.CheckPrecondFn
	opts.CheckPrecondFn = nil // do not need to apply pre-conditions at lower layer.
	opts.NoLock = true        // no locks needed at lower levels for getObjectInfo()
	objInfo, zIdx, err := z.getLatestObjectInfoWithIdx(ctx, bucket, object, opts)
	if err != nil {
		if objInfo.DeleteMarker {
			if opts.VersionID == "" {

	}

	AssertEqual(t, "varchar", strings.ToLower(ct.DatabaseTypeName()))

	err = DB.Table("diff_types").AutoMigrate(&DiffType1{})
	if err != nil {
		t.Errorf("AutoMigrate err:%v", err)
	}

	ct, err = findColumnType(&DiffType{}, "name")
	if err != nil {
		t.Errorf("findColumnType err:%v", err)
	}

	AssertEqual(t, "text", strings.ToLower(ct.DatabaseTypeName()))
}

	// Small file threshold below which data accompanies metadata from storage layer.
	smallFileThreshold = 128 * humanize.KiByte // Optimized for NVMe/SSDs

	// For hardrives it is possible to set this to a lower value to avoid any
	// spike in latency. But currently we are simply keeping it optimal for SSDs.

	// bigFileThreshold is the point where we add readahead to put operations.
	bigFileThreshold = 128 * humanize.MiByte

   * accommodate as many threads as will ever concurrently modify the table. Using a significantly
   * higher value than you need can waste space and time, and a significantly lower value can lead
   * to thread contention. But overestimates and underestimates within an order of magnitude do not
   * usually have much noticeable impact. A value of one permits only one thread to modify the cache

			markDelete = false
		}
		if opts.VersionPurgeStatus() == replication.VersionPurgeComplete {
			markDelete = false
		}
		// now, since VersionPurgeStatus() is already set, we can let the
		// lower layers decide this. This fixes a regression that was introduced
		// in PR #14555 where !VersionPurgeStatus.Empty() is automatically
		// considered as Delete marker true to avoid listing such objects by