1 // Licensed under the Apache License, Version 2.0 (the "License"); you may not 2 // use this file except in compliance with the License. You may obtain a copy of 3 // the License at 4 // 5 // http://www.apache.org/licenses/LICENSE-2.0 6 // 7 // Unless required by applicable law or agreed to in writing, software 8 // distributed under the License is distributed on an "AS IS" BASIS, WITHOUT 9 // WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the 10 // License for the specific language governing permissions and limitations under 11 // the License. 12 13 // Package cdb provides the core CouchDB types. 14 package cdb 15 16 import ( 17 "fmt" 18 ) 19 20 // RevHistory represents the recent ancestors of a revision. 21 type RevHistory struct { 22 Start int64 `json:"start" yaml:"start"` 23 IDs []string `json:"ids" yaml:"ids"` 24 } 25 26 // Ancestors returns the full, known revision history, newest first, starting 27 // with the current rev. 28 func (h *RevHistory) Ancestors() []string { 29 history := make([]string, len(h.IDs)) 30 for i, id := range h.IDs { 31 history[i] = fmt.Sprintf("%d-%s", h.Start-int64(i), id) 32 } 33 return history 34 } 35 36 // AddRevision returns a new history, with rev added. 37 func (h *RevHistory) AddRevision(rev RevID) *RevHistory { 38 return &RevHistory{ 39 Start: rev.Seq, 40 IDs: append([]string{rev.Sum}, h.IDs...), 41 } 42 } 43