mirror of https://github.com/harness/drone.git
126 lines
3.1 KiB
Go
126 lines
3.1 KiB
Go
// Copyright 2023 Harness, Inc.
|
|
//
|
|
// Licensed 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 parser
|
|
|
|
import (
|
|
"bufio"
|
|
"io"
|
|
"regexp"
|
|
)
|
|
|
|
type DiffFileHunkHeaders struct {
|
|
FileHeader DiffFileHeader
|
|
HunksHeaders []HunkHeader
|
|
}
|
|
|
|
var regExpDiffFileHeader = regexp.MustCompile(`^diff --git a/(.+) b/(.+)$`)
|
|
|
|
func ParseDiffFileHeader(line string) (DiffFileHeader, bool) {
|
|
groups := regExpDiffFileHeader.FindStringSubmatch(line)
|
|
if groups == nil {
|
|
return DiffFileHeader{}, false
|
|
}
|
|
|
|
return DiffFileHeader{
|
|
OldFileName: groups[1],
|
|
NewFileName: groups[2],
|
|
Extensions: map[string]string{},
|
|
}, true
|
|
}
|
|
|
|
// GetHunkHeaders parses git diff output and returns all diff headers for all files.
|
|
// See for documentation: https://git-scm.com/docs/git-diff#generate_patch_text_with_p
|
|
func GetHunkHeaders(r io.Reader) ([]*DiffFileHunkHeaders, error) {
|
|
bufrd := bufio.NewReader(r)
|
|
|
|
var currentFile *DiffFileHunkHeaders
|
|
var result []*DiffFileHunkHeaders
|
|
|
|
for {
|
|
// Consume the line but get only the first 4K of it...
|
|
// We're interested only in the hunk headers anyway, and they are never longer than this.
|
|
line, err := readLinePrefix(bufrd, 4096)
|
|
if err != nil && err != io.EOF { //nolint:errorlint
|
|
return nil, err
|
|
}
|
|
|
|
if len(line) == 0 {
|
|
break
|
|
}
|
|
|
|
if h, ok := ParseDiffFileHeader(line); ok {
|
|
if currentFile != nil {
|
|
result = append(result, currentFile)
|
|
}
|
|
currentFile = &DiffFileHunkHeaders{
|
|
FileHeader: h,
|
|
HunksHeaders: nil,
|
|
}
|
|
|
|
continue
|
|
}
|
|
|
|
if currentFile == nil {
|
|
// should not happen: we reached the hunk header without first finding the file header.
|
|
return nil, ErrHunkNotFound
|
|
}
|
|
|
|
if h, ok := ParseDiffHunkHeader(line); ok {
|
|
currentFile.HunksHeaders = append(currentFile.HunksHeaders, h)
|
|
continue
|
|
}
|
|
|
|
if headerKey, headerValue := ParseDiffFileExtendedHeader(line); headerKey != "" {
|
|
currentFile.FileHeader.Extensions[headerKey] = headerValue
|
|
continue
|
|
}
|
|
}
|
|
|
|
if currentFile != nil {
|
|
result = append(result, currentFile)
|
|
}
|
|
|
|
return result, nil
|
|
}
|
|
|
|
// readLinePrefix will consume the entire line from the reader,
|
|
// but will return only the first maxLen bytes from it - the rest is discarded.
|
|
// Returns io.EOF when the end of the input has been reached.
|
|
func readLinePrefix(br *bufio.Reader, maxLen int) (line string, err error) {
|
|
for {
|
|
var raw []byte
|
|
var isPrefix bool
|
|
|
|
raw, isPrefix, err = br.ReadLine()
|
|
if err != nil && err != io.EOF { //nolint:errorlint
|
|
return "", err
|
|
}
|
|
|
|
if needMore := maxLen - len(line); needMore > 0 {
|
|
if len(raw) > needMore {
|
|
line += string(raw[:needMore])
|
|
} else {
|
|
line += string(raw)
|
|
}
|
|
}
|
|
|
|
if !isPrefix || len(raw) == 0 {
|
|
break
|
|
}
|
|
}
|
|
|
|
return line, err
|
|
}
|