if days == 0 {
		return modTime
	}
	t := modTime.UTC().Add(time.Duration(days+1) * 24 * time.Hour)
	return t.Truncate(24 * time.Hour)
}

// SetPredictionHeaders sets time to expiry and transition headers on w for a
// given obj.
func (lc Lifecycle) SetPredictionHeaders(w http.ResponseWriter, obj ObjectOpts) {
	event := lc.eval(obj, time.Time{}, 0)
	switch event.Action {

		w.Header()[xhttp.AmzStorageClass] = []string{filterStorageClass(ctx, objInfo.TransitionedObject.Tier)}
	}

	if lc, err := globalLifecycleSys.Get(objInfo.Bucket); err == nil {
		lc.SetPredictionHeaders(w, objInfo.ToLifecycleOpts())
	}

	if v, ok := objInfo.UserDefined[ReservedMetadataPrefix+"compression"]; ok {
		if i := strings.LastIndexByte(v, '/'); i >= 0 {
			v = v[i+1:]
		}

		}
	}

	if objInfo.Bucket != "" && objInfo.Name != "" {
		if lc, err := globalLifecycleSys.Get(objInfo.Bucket); err == nil && !del {
			lc.SetPredictionHeaders(w, objInfo.ToLifecycleOpts())
		}
	}
	cs, _ := objInfo.decryptChecksums(0, h)
	hash.AddChecksumHeader(w, cs)
}

			expRuleID:   0,
			transRuleID: 1,
		},
		{
			obj:         obj2,
			expRuleID:   0,
			transRuleID: 2,
		},
	}
	for i, tc := range tests {
		w := httptest.NewRecorder()
		lc.SetPredictionHeaders(w, tc.obj)
		if expHdrs, ok := w.Header()[xhttp.AmzExpiration]; ok && !strings.Contains(expHdrs[0], lc.Rules[tc.expRuleID].ID) {
			t.Fatalf("Test %d: Expected %s header", i+1, xhttp.AmzExpiration)
		}