github.com/joelanford/operator-sdk@v0.8.2/internal/util/diffutil/diff_util.go (about) 1 // Copyright 2018 The Operator-SDK Authors 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 package diffutil 16 17 import ( 18 "bytes" 19 "regexp" 20 "strings" 21 22 "github.com/sergi/go-diff/diffmatchpatch" 23 ) 24 25 func Diff(a, b string) string { 26 dmp := diffmatchpatch.New() 27 28 wSrc, wDst, warray := dmp.DiffLinesToRunes(a, b) 29 diffs := dmp.DiffMainRunes(wSrc, wDst, false) 30 diffs = dmp.DiffCharsToLines(diffs, warray) 31 var buff bytes.Buffer 32 for _, diff := range diffs { 33 text := diff.Text 34 35 switch diff.Type { 36 case diffmatchpatch.DiffInsert: 37 _, _ = buff.WriteString("\x1b[32m") 38 _, _ = buff.WriteString(prefixLines(text, "+")) 39 _, _ = buff.WriteString("\x1b[0m") 40 case diffmatchpatch.DiffDelete: 41 _, _ = buff.WriteString("\x1b[31m") 42 _, _ = buff.WriteString(prefixLines(text, "-")) 43 _, _ = buff.WriteString("\x1b[0m") 44 case diffmatchpatch.DiffEqual: 45 _, _ = buff.WriteString(prefixLines(text, " ")) 46 } 47 } 48 return buff.String() 49 } 50 51 func prefixLines(s, prefix string) string { 52 var buf bytes.Buffer 53 lines := strings.Split(s, "\n") 54 ls := regexp.MustCompile("^") 55 for _, line := range lines[:len(lines)-1] { 56 buf.WriteString(ls.ReplaceAllString(line, prefix)) 57 buf.WriteString("\n") 58 } 59 return buf.String() 60 }