| // Licensed to the Apache Software Foundation (ASF) under one or more |
| // contributor license agreements. See the NOTICE file distributed with |
| // this work for additional information regarding copyright ownership. |
| // The ASF licenses this file to You under the Apache License, Version 2.0 |
| // (the "License"); you may not use this file except in compliance with |
| // the License. You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| // Package diff implements diffing. |
| // |
| // Should primarily be used for testing. |
| package diff |
| |
| // Largely copied from https://github.com/golang/go/blob/master/src/cmd/gofmt/gofmt.go |
| // |
| // Copyright 2009 The Go Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| // |
| // https://github.com/golang/go/blob/master/LICENSE |
| |
| import ( |
| "bytes" |
| "context" |
| "fmt" |
| "os" |
| "path/filepath" |
| "runtime" |
| ) |
| |
| import ( |
| "github.com/apache/dubbo-kubernetes/pkg/bufman/pkg/command" |
| ) |
| |
| // Diff does a diff. |
| // |
| // Returns nil if no diff. |
| func Diff( |
| ctx context.Context, |
| runner command.Runner, |
| b1 []byte, |
| b2 []byte, |
| filename1 string, |
| filename2 string, |
| options ...DiffOption, |
| ) ([]byte, error) { |
| diffOptions := newDiffOptions() |
| for _, option := range options { |
| option(diffOptions) |
| } |
| return doDiff( |
| ctx, |
| runner, |
| b1, |
| b2, |
| filename1, |
| filename2, |
| diffOptions.suppressCommands, |
| diffOptions.suppressTimestamps, |
| ) |
| } |
| |
| // DiffOption is an option for Diff. |
| type DiffOption func(*diffOptions) |
| |
| // DiffWithSuppressCommands returns a new DiffOption that suppresses printing of commands. |
| func DiffWithSuppressCommands() DiffOption { |
| return func(diffOptions *diffOptions) { |
| diffOptions.suppressCommands = true |
| } |
| } |
| |
| // DiffWithSuppressCommands returns a new DiffOption that suppresses printing of timestamps. |
| func DiffWithSuppressTimestamps() DiffOption { |
| return func(diffOptions *diffOptions) { |
| diffOptions.suppressTimestamps = true |
| } |
| } |
| |
| func doDiff( |
| ctx context.Context, |
| runner command.Runner, |
| b1 []byte, |
| b2 []byte, |
| filename1 string, |
| filename2 string, |
| suppressCommands bool, |
| suppressTimestamps bool, |
| ) ([]byte, error) { |
| if bytes.Equal(b1, b2) { |
| return nil, nil |
| } |
| |
| f1, err := writeTempFile("", "", b1) |
| if err != nil { |
| return nil, err |
| } |
| defer func() { |
| _ = os.Remove(f1) |
| }() |
| |
| f2, err := writeTempFile("", "", b2) |
| if err != nil { |
| return nil, err |
| } |
| defer func() { |
| _ = os.Remove(f2) |
| }() |
| |
| binaryPath := "diff" |
| if runtime.GOOS == "plan9" { |
| binaryPath = "/bin/ape/diff" |
| } |
| |
| buffer := bytes.NewBuffer(nil) |
| err = runner.Run( |
| ctx, |
| binaryPath, |
| command.RunWithArgs("-u", f1, f2), |
| command.RunWithStdout(buffer), |
| command.RunWithStderr(buffer), |
| ) |
| data := buffer.Bytes() |
| if len(data) > 0 { |
| // diff exits with a non-zero status when the files don't match. |
| // Ignore that failure as long as we get output. |
| return tryModifyHeader(data, filename1, filename2, suppressCommands, suppressTimestamps), nil |
| } |
| return nil, err |
| } |
| |
| func writeTempFile(dir string, prefix string, data []byte) (string, error) { |
| file, err := os.CreateTemp(dir, prefix) |
| if err != nil { |
| return "", err |
| } |
| if len(data) > 0 { |
| _, err = file.Write(data) |
| } |
| if err1 := file.Close(); err == nil { |
| err = err1 |
| } |
| if err != nil { |
| _ = os.Remove(file.Name()) |
| return "", err |
| } |
| return file.Name(), nil |
| } |
| |
| func tryModifyHeader( |
| diff []byte, |
| filename1 string, |
| filename2 string, |
| suppressCommands bool, |
| suppressTimestamps bool, |
| ) []byte { |
| bs := bytes.SplitN(diff, []byte{'\n'}, 3) |
| if len(bs) < 3 { |
| return diff |
| } |
| // Preserve timestamps. |
| var t0, t1 []byte |
| if !suppressTimestamps { |
| if i := bytes.LastIndexByte(bs[0], '\t'); i != -1 { |
| t0 = bs[0][i:] |
| } |
| if i := bytes.LastIndexByte(bs[1], '\t'); i != -1 { |
| t1 = bs[1][i:] |
| } |
| } |
| // Always print filepath with slash separator. |
| filename1 = filepath.ToSlash(filename1) |
| filename2 = filepath.ToSlash(filename2) |
| if filename1 == filename2 { |
| filename1 = filename1 + ".orig" |
| } |
| bs[0] = []byte(fmt.Sprintf("--- %s%s", filename1, t0)) |
| bs[1] = []byte(fmt.Sprintf("+++ %s%s", filename2, t1)) |
| if !suppressCommands { |
| bs = append( |
| [][]byte{ |
| []byte(fmt.Sprintf("diff -u %s %s", filename1, filename2)), |
| }, |
| bs..., |
| ) |
| } |
| return bytes.Join(bs, []byte{'\n'}) |
| } |
| |
| type diffOptions struct { |
| suppressCommands bool |
| suppressTimestamps bool |
| } |
| |
| func newDiffOptions() *diffOptions { |
| return &diffOptions{} |
| } |