gitea/build/codeformat/formatimports.go
flynnnnnnnnnn e81ccc406b
Implement FSFE REUSE for golang files (#21840)
Change all license headers to comply with REUSE specification.

Fix #16132

Co-authored-by: flynnnnnnnnnn <flynnnnnnnnnn@github>
Co-authored-by: John Olheiser <john.olheiser@gmail.com>
2022-11-27 18:20:29 +00:00

196 lines
4.5 KiB
Go

// Copyright 2021 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package codeformat
import (
"bytes"
"errors"
"io"
"os"
"sort"
"strings"
)
var importPackageGroupOrders = map[string]int{
"": 1, // internal
"code.gitea.io/gitea/": 2,
}
var errInvalidCommentBetweenImports = errors.New("comments between imported packages are invalid, please move comments to the end of the package line")
var (
importBlockBegin = []byte("\nimport (\n")
importBlockEnd = []byte("\n)")
)
type importLineParsed struct {
group string
pkg string
content string
}
func parseImportLine(line string) (*importLineParsed, error) {
il := &importLineParsed{content: line}
p1 := strings.IndexRune(line, '"')
if p1 == -1 {
return nil, errors.New("invalid import line: " + line)
}
p1++
p := strings.IndexRune(line[p1:], '"')
if p == -1 {
return nil, errors.New("invalid import line: " + line)
}
p2 := p1 + p
il.pkg = line[p1:p2]
pDot := strings.IndexRune(il.pkg, '.')
pSlash := strings.IndexRune(il.pkg, '/')
if pDot != -1 && pDot < pSlash {
il.group = "domain-package"
}
for groupName := range importPackageGroupOrders {
if groupName == "" {
continue // skip internal
}
if strings.HasPrefix(il.pkg, groupName) {
il.group = groupName
}
}
return il, nil
}
type (
importLineGroup []*importLineParsed
importLineGroupMap map[string]importLineGroup
)
func formatGoImports(contentBytes []byte) ([]byte, error) {
p1 := bytes.Index(contentBytes, importBlockBegin)
if p1 == -1 {
return nil, nil
}
p1 += len(importBlockBegin)
p := bytes.Index(contentBytes[p1:], importBlockEnd)
if p == -1 {
return nil, nil
}
p2 := p1 + p
importGroups := importLineGroupMap{}
r := bytes.NewBuffer(contentBytes[p1:p2])
eof := false
for !eof {
line, err := r.ReadString('\n')
eof = err == io.EOF
if err != nil && !eof {
return nil, err
}
line = strings.TrimSpace(line)
if line != "" {
if strings.HasPrefix(line, "//") || strings.HasPrefix(line, "/*") {
return nil, errInvalidCommentBetweenImports
}
importLine, err := parseImportLine(line)
if err != nil {
return nil, err
}
importGroups[importLine.group] = append(importGroups[importLine.group], importLine)
}
}
var groupNames []string
for groupName, importLines := range importGroups {
groupNames = append(groupNames, groupName)
sort.Slice(importLines, func(i, j int) bool {
return strings.Compare(importLines[i].pkg, importLines[j].pkg) < 0
})
}
sort.Slice(groupNames, func(i, j int) bool {
n1 := groupNames[i]
n2 := groupNames[j]
o1 := importPackageGroupOrders[n1]
o2 := importPackageGroupOrders[n2]
if o1 != 0 && o2 != 0 {
return o1 < o2
}
if o1 == 0 && o2 == 0 {
return strings.Compare(n1, n2) < 0
}
return o1 != 0
})
formattedBlock := bytes.Buffer{}
for _, groupName := range groupNames {
hasNormalImports := false
hasDummyImports := false
// non-dummy import comes first
for _, importLine := range importGroups[groupName] {
if strings.HasPrefix(importLine.content, "_") {
hasDummyImports = true
} else {
formattedBlock.WriteString("\t" + importLine.content + "\n")
hasNormalImports = true
}
}
// dummy (_ "pkg") comes later
if hasDummyImports {
if hasNormalImports {
formattedBlock.WriteString("\n")
}
for _, importLine := range importGroups[groupName] {
if strings.HasPrefix(importLine.content, "_") {
formattedBlock.WriteString("\t" + importLine.content + "\n")
}
}
}
formattedBlock.WriteString("\n")
}
formattedBlockBytes := bytes.TrimRight(formattedBlock.Bytes(), "\n")
var formattedBytes []byte
formattedBytes = append(formattedBytes, contentBytes[:p1]...)
formattedBytes = append(formattedBytes, formattedBlockBytes...)
formattedBytes = append(formattedBytes, contentBytes[p2:]...)
return formattedBytes, nil
}
// FormatGoImports format the imports by our rules (see unit tests)
func FormatGoImports(file string, doWriteFile bool) error {
f, err := os.Open(file)
if err != nil {
return err
}
var contentBytes []byte
{
defer f.Close()
contentBytes, err = io.ReadAll(f)
if err != nil {
return err
}
}
formattedBytes, err := formatGoImports(contentBytes)
if err != nil {
return err
}
if formattedBytes == nil {
return nil
}
if bytes.Equal(contentBytes, formattedBytes) {
return nil
}
if doWriteFile {
f, err = os.OpenFile(file, os.O_TRUNC|os.O_WRONLY, 0o644)
if err != nil {
return err
}
defer f.Close()
_, err = f.Write(formattedBytes)
return err
}
return err
}