Adding gofumpt (#1177)

CHANGELOG.md

@@ -1,6 +1,9 @@
 Follow the news and releases on our [twitter](https://twitter.com/golangci) and our [blog](https://medium.com/golangci).
 There is the most valuable changes log:
 
+### June 2020
+1. Add new linters: `gofumpt`
+
 ### May 2020
 
 1. Add new linters: `nolintlint`, `goerr113`

go.mod

@@ -57,6 +57,7 @@ require (
 	golang.org/x/tools v0.0.0-20200519015757-0d0afa43d58a
 	gopkg.in/yaml.v2 v2.3.0
 	honnef.co/go/tools v0.0.1-2020.1.4
+	mvdan.cc/gofumpt v0.0.0-20200513141252-abc0db2c416a
 	mvdan.cc/interfacer v0.0.0-20180901003855-c20040233aed
 	mvdan.cc/lint v0.0.0-20170908181259-adc824a0674b // indirect
 	mvdan.cc/unparam v0.0.0-20190720180237-d51796306d8f

go.sum

@@ -145,6 +145,9 @@ github.com/google/go-cmp v0.2.0 h1:+dTQ8DZQJz0Mb/HjFlkptS1FeQ4cWSnN941F8aEG4SQ=
 github.com/google/go-cmp v0.2.0/go.mod h1:oXzfMopK8JAjlY9xF4vHSVASa0yLyX7SntLO5aqRK0M=
 github.com/google/go-cmp v0.3.0 h1:crn/baboCvb5fXaQ0IJ1SGTsTVrWpDsCWC8EGETZijY=
 github.com/google/go-cmp v0.3.0/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
+github.com/google/go-cmp v0.4.0 h1:xsAVV57WRhGj6kEIi8ReJzQlHHqcBYCElAvkovg3B/4=
+github.com/google/go-cmp v0.4.0/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+github.com/google/martian v2.1.0+incompatible h1:/CP5g8u/VJHijgedC/Legn3BAbAaWPgecwXBIDzw5no=
 github.com/google/martian v2.1.0+incompatible/go.mod h1:9I4somxYTbIHy5NJKHRl3wXiIaQGbYVAs8BPL6v8lEs=
 github.com/google/pprof v0.0.0-20181206194817-3ea8567a2e57/go.mod h1:zfwlbNMJ+OItoe0UupaVj+oy1omPYYDuagoSzA8v9mc=
 github.com/google/pprof v0.0.0-20190515194954-54271f7e092f/go.mod h1:zfwlbNMJ+OItoe0UupaVj+oy1omPYYDuagoSzA8v9mc=
@@ -307,6 +310,7 @@ github.com/quasilyte/go-ruleguard v0.1.2-0.20200318202121-b00d7a75d3d8 h1:Dvnesv
 github.com/quasilyte/go-ruleguard v0.1.2-0.20200318202121-b00d7a75d3d8/go.mod h1:CGFX09Ci3pq9QZdj86B+VGIdNj4VyCo2iPOGS9esB/k=
 github.com/rogpeppe/fastuuid v0.0.0-20150106093220-6724a57986af/go.mod h1:XWv6SoW27p1b0cqNHllgS5HIMJraePCO15w5zCzIWYg=
 github.com/rogpeppe/go-internal v1.3.0/go.mod h1:M8bDsm7K2OlrFYOpmOWEs/qY81heoFRclV5y23lUDJ4=
+github.com/rogpeppe/go-internal v1.5.2/go.mod h1:xXDCJY+GAPziupqXw64V24skbSoqbTEfhy4qGm1nDQc=
 github.com/russross/blackfriday/v2 v2.0.1/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
 github.com/ryancurrah/gomodguard v1.1.0 h1:DWbye9KyMgytn8uYpuHkwf0RHqAYO6Ay/D0TbCpPtVU=
 github.com/ryancurrah/gomodguard v1.1.0/go.mod h1:4O8tr7hBODaGE6VIhfJDHcwzh5GUccKSJBU0UMXJFVM=
@@ -359,8 +363,6 @@ github.com/stretchr/testify v1.4.0 h1:2E4SXV/wtOkTonXsotYi4li6zVWxYlZuYNCXe9XRJy
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
 github.com/stretchr/testify v1.5.1 h1:nOGnQDM7FYENwehXlg/kFVnos3rEvtKTjRvOWSzb6H4=
 github.com/stretchr/testify v1.5.1/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5cxcmMvtA=
-github.com/stretchr/testify v1.6.0 h1:jlIyCplCJFULU/01vCkhKuTyc3OorI3bJFuw6obfgho=
-github.com/stretchr/testify v1.6.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.6.1 h1:hDPOHmpOpP40lSULcqw7IrRb/u7w6RpDC9399XyoNd0=
 github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/subosito/gotenv v1.2.0 h1:Slr1R9HxAlEKefgq5jn9U+DnETlIUa6HfgEzj0g5d7s=
@@ -519,6 +521,7 @@ golang.org/x/tools v0.0.0-20200331202046-9d5940d49312/go.mod h1:EkVYQZoAsY45+roY
 golang.org/x/tools v0.0.0-20200414032229-332987a829c3/go.mod h1:EkVYQZoAsY45+roYkvgYkIh4xh/qjgUK9TdY2XT94GE=
 golang.org/x/tools v0.0.0-20200422022333-3d57cf2e726e h1:3Dzrrxi54Io7Aoyb0PYLsI47K2TxkRQg+cqUn+m04do=
 golang.org/x/tools v0.0.0-20200422022333-3d57cf2e726e/go.mod h1:EkVYQZoAsY45+roYkvgYkIh4xh/qjgUK9TdY2XT94GE=
+golang.org/x/tools v0.0.0-20200428185508-e9a00ec82136/go.mod h1:EkVYQZoAsY45+roYkvgYkIh4xh/qjgUK9TdY2XT94GE=
 golang.org/x/tools v0.0.0-20200519015757-0d0afa43d58a h1:gILuVKC+ZPD6g/tj6zBOdnOH1ZHI0zZ86+KLMogc6/s=
 golang.org/x/tools v0.0.0-20200519015757-0d0afa43d58a/go.mod h1:EkVYQZoAsY45+roYkvgYkIh4xh/qjgUK9TdY2XT94GE=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7 h1:9zdDQZ7Thm29KFXgAX/+yaf3eVbP7djjWp/dXAppNCc=
@@ -582,6 +585,8 @@ honnef.co/go/tools v0.0.0-20190418001031-e561f6794a2a/go.mod h1:rf3lG4BRIbNafJWh
 honnef.co/go/tools v0.0.1-2019.2.3/go.mod h1:a3bituU0lyd329TUQxRnasdCoJDkEUEAqEt0JzvZhAg=
 honnef.co/go/tools v0.0.1-2020.1.4 h1:UoveltGrhghAA7ePc+e+QYDHXrBps2PqFZiHkGR/xK8=
 honnef.co/go/tools v0.0.1-2020.1.4/go.mod h1:X/FiERA/W4tHapMX5mGpAtMSVEeEUOyHaw9vFzvIQ3k=
+mvdan.cc/gofumpt v0.0.0-20200513141252-abc0db2c416a h1:TTEzidAa7rn93JGy1ACigx6o9VcsRLKG7qICdErmvUs=
+mvdan.cc/gofumpt v0.0.0-20200513141252-abc0db2c416a/go.mod h1:4q/PlrZKQLU5MowSvCKM3U4xJUPtJ8vKWx7vsWFJ3MI=
 mvdan.cc/interfacer v0.0.0-20180901003855-c20040233aed h1:WX1yoOaKQfddO/mLzdV4wptyWgoH/6hwLs7QHTixo0I=
 mvdan.cc/interfacer v0.0.0-20180901003855-c20040233aed/go.mod h1:Xkxe497xwlCKkIaQYRfC7CSLworTXY9RMqwhhCm+8Nc=
 mvdan.cc/lint v0.0.0-20170908181259-adc824a0674b h1:DxJ5nJdkhDlLok9K6qO+5290kphDJbHOQO1DFFFTeBo=

pkg/golinters/gofumpt.go

@@ -0,0 +1,78 @@
+package golinters
+
+import (
+	"bytes"
+	"fmt"
+	"go/token"
+	"io/ioutil"
+	"strings"
+	"sync"
+
+	"golang.org/x/tools/go/analysis"
+	"mvdan.cc/gofumpt/format"
+
+	"github.com/golangci/golangci-lint/pkg/golinters/goanalysis"
+	"github.com/golangci/golangci-lint/pkg/lint/linter"
+	"github.com/golangci/golangci-lint/pkg/result"
+)
+
+const gofumptName = "gofumpt"
+
+func NewGofumpt() *goanalysis.Linter {
+	var mu sync.Mutex
+	var resIssues []goanalysis.Issue
+
+	analyzer := &analysis.Analyzer{
+		Name: gofumptName,
+		Doc:  goanalysis.TheOnlyanalyzerDoc,
+	}
+	return goanalysis.NewLinter(
+		gofumptName,
+		"Gofumpt checks whether code was gofumpt-ed.",
+		[]*analysis.Analyzer{analyzer},
+		nil,
+	).WithContextSetter(func(lintCtx *linter.Context) {
+		analyzer.Run = func(pass *analysis.Pass) (interface{}, error) {
+			var fileNames []string
+			for _, f := range pass.Files {
+				pos := pass.Fset.PositionFor(f.Pos(), false)
+				fileNames = append(fileNames, pos.Filename)
+			}
+
+			var issues []goanalysis.Issue
+
+			for _, f := range fileNames {
+				input, err := ioutil.ReadFile(f)
+				if err != nil {
+					return nil, fmt.Errorf("unable to open file %s: %w", f, err)
+				}
+				output, err := format.Source(input, "")
+				if err != nil {
+					return nil, fmt.Errorf("error while running gofumpt: %w", err)
+				}
+				if !bytes.Equal(input, output) {
+					issues = append(issues, goanalysis.NewIssue(&result.Issue{
+						FromLinter: gofumptName,
+						Text:       "File is not `gofumpt`-ed",
+						Pos: token.Position{
+							Filename: f,
+							Line:     strings.Count(string(input), "\n"),
+						},
+					}, pass))
+				}
+			}
+
+			if len(issues) == 0 {
+				return nil, nil
+			}
+
+			mu.Lock()
+			resIssues = append(resIssues, issues...)
+			mu.Unlock()
+
+			return nil, nil
+		}
+	}).WithIssuesReporter(func(*linter.Context) []goanalysis.Issue {
+		return resIssues
+	}).WithLoadMode(goanalysis.LoadModeSyntax)
+}

pkg/lint/lintersdb/manager.go

@@ -195,6 +195,9 @@ func (m Manager) GetAllSupportedLinterConfigs() []*linter.Config {
 			WithPresets(linter.PresetFormatting).
 			WithAutoFix().
 			WithURL("https://golang.org/cmd/gofmt/"),
+		linter.NewConfig(golinters.NewGofumpt()).
+			WithPresets(linter.PresetFormatting).
+			WithURL("https://github.com/mvdan/gofumpt"),
 		linter.NewConfig(golinters.NewGoimports()).
 			WithPresets(linter.PresetFormatting).
 			WithAutoFix().

test/testdata/gofumpt.go

@@ -0,0 +1,11 @@
+//args: -Egofumpt
+package testdata
+
+import "fmt"
+
+func GofumptNewLine() {
+
+	fmt.Println("foo")
+}
+
+// ERROR "File is not `gofumpt`-ed"