Add linter for nolint

Linter can check that nolint statements are properly formatted and also that all
nolint statements are used.

Author: ashanbrown

.golangci.example.yml

@@ -224,6 +224,17 @@ linters-settings:
     simple: true
     range-loops: true # Report preallocation suggestions on range loops, true by default
     for-loops: false # Report preallocation suggestions on for loops, false by default
+  nolintlint:
+    # Enable to ensure that nolint directives are all used. Default is true.
+    allow-unused: false
+    # Disable to ensure that nolint directives don't have a leading space. Default is true.
+    allow-leading-space: true
+    # Exclude following linters from requiring an explanation.  Default is [].
+    allow-no-explanation: []
+    # Enable to require an explanation after each nolint directive. Default is false.
+    require-explanation: true
+    # Enable to require an explanation after each nolint directive. Default is false.
+    require-specific: true
   rowserrcheck:
     packages:
       - github.com/jmoiron/sqlx

.golangci.yml

@@ -54,6 +54,11 @@ linters-settings:
     suggest-new: true
   misspell:
     locale: US
+  nolintlint:
+    allow-leading-space: true # don't require machine-readable nolint directives (i.e. with no leading space)
+    allow-unused: false # report any unused nolint directives
+    require-explanation: false # don't require an explanation for nolint directives
+    require-specific: false # don't require nolint directives to be specific about which linter is being skipped
 
 linters:
   # please, do not use `enable-all`: it's deprecated and will be removed soon.
@@ -84,6 +89,7 @@ linters:
     - lll
     - misspell
     - nakedret
+    - nolintlint
     - rowserrcheck
     - scopelint
     - staticcheck

README.md

@@ -231,6 +231,7 @@ maligned: Tool to detect Go structs that would take less memory if their fields
 misspell: Finds commonly misspelled English words in comments [fast: true, auto-fix: true]
 nakedret: Finds naked returns in functions greater than a specified function length [fast: true, auto-fix: false]
 nestif: Reports deeply nested if statements [fast: true, auto-fix: false]
+nolintlint: Reports ill-formed or insufficient nolint directives [fast: true, auto-fix: false]
 prealloc: Finds slice declarations that could potentially be preallocated [fast: true, auto-fix: false]
 rowserrcheck: checks whether Err of rows is checked successfully [fast: true, auto-fix: false]
 scopelint: Scopelint checks for unpinned variables in go programs [fast: true, auto-fix: false]
@@ -496,6 +497,7 @@ golangci-lint help linters
 - [godot](https://github.com/tetafro/godot) - Check if comments end in a period
 - [testpackage](https://github.com/maratori/testpackage) - linter that makes you use a separate _test package
 - [nestif](https://github.com/nakabonne/nestif) - Reports deeply nested if statements
+- [nolintlint](https://github.com/golangci-lint/pkg/golinters/nolintlint) - Reports ill-formed or insufficient nolint directives
 
 ## Configuration
 
@@ -544,7 +546,7 @@ Flags:
       --disable-all                    Disable all linters
   -p, --presets strings                Enable presets (bugs|complexity|format|performance|style|unused) of linters. Run 'golangci-lint linters' to see them. This option implies option --disable-all
       --fast                           Run only fast linters from enabled linters set (first run won't be fast)
-  -e, --exclude strings                Exclude issue by regexp
+  -e, --exclude strings                ExcludeLinters issue by regexp
       --exclude-use-default            Use or not use default excludes:
                                          # EXC0001 errcheck: Almost all programs ignore errors on these functions and in most cases it's ok
                                          - Error return value of .((os\.)?std(out|err)\..*|.*Close|.*Flush|os\.Remove(All)?|.*printf?|os\.(Un)?Setenv). is not checked
@@ -843,6 +845,17 @@ linters-settings:
     simple: true
     range-loops: true # Report preallocation suggestions on range loops, true by default
     for-loops: false # Report preallocation suggestions on for loops, false by default
+  nolintlint:
+    # Enable to ensure that nolint directives are all used. Default is true.
+    allow-unused: false
+    # Disable to ensure that nolint directives don't have a leading space. Default is true.
+    allow-leading-space: true
+    # Exclude following linters from requiring an explanation.  Default is [].
+    allow-no-explanation: []
+    # Enable to require an explanation after each nolint directive. Default is false.
+    require-explanation: true
+    # Enable to require an explanation after each nolint directive. Default is false.
+    require-specific: true
   rowserrcheck:
     packages:
       - github.com/jmoiron/sqlx
@@ -1032,6 +1045,11 @@ linters-settings:
     suggest-new: true
   misspell:
     locale: US
+  nolintlint:
+    allow-leading-space: true # don't require machine-readable nolint directives (i.e. with no leading space)
+    allow-unused: false # report any unused nolint directives
+    require-explanation: false # don't require an explanation for nolint directives
+    require-specific: false # don't require nolint directives to be specific about which linter is being skipped
 
 linters:
   # please, do not use `enable-all`: it's deprecated and will be removed soon.
@@ -1062,6 +1080,7 @@ linters:
     - lll
     - misspell
     - nakedret
+    - nolintlint
     - rowserrcheck
     - scopelint
     - staticcheck
@@ -1298,6 +1317,7 @@ Thanks to developers and authors of used linters:
 - [tetafro](https://github.com/tetafro)
 - [maratori](https://github.com/maratori)
 - [nakabonne](https://github.com/nakabonne)
+- [golangci-lint](https://github.com/golangci-lint)
 
 ## Changelog
 

pkg/commands/run.go

@@ -187,7 +187,7 @@ func initFlagSet(fs *pflag.FlagSet, cfg *config.Config, m *lintersdb.Manager, is
 
 	// Issues config
 	ic := &cfg.Issues
-	fs.StringSliceVarP(&ic.ExcludePatterns, "exclude", "e", nil, wh("Exclude issue by regexp"))
+	fs.StringSliceVarP(&ic.ExcludePatterns, "exclude", "e", nil, wh("ExcludeLinters issue by regexp"))
 	fs.BoolVar(&ic.UseDefaultExcludes, "exclude-use-default", true, getDefaultIssueExcludeHelp())
 	fs.BoolVar(&ic.ExcludeCaseSensitive, "exclude-case-sensitive", false, wh("If set to true exclude "+
 		"and exclude rules regular expressions are case sensitive"))
@@ -441,7 +441,7 @@ func (e *Executor) executeRun(_ *cobra.Command, args []string) {
 // to be removed when deadline is finally decommissioned
 func (e *Executor) setTimeoutToDeadlineIfOnlyDeadlineIsSet() {
 	//lint:ignore SA1019 We want to promoted the deprecated config value when needed
-	deadlineValue := e.cfg.Run.Deadline // nolint: staticcheck
+	deadlineValue := e.cfg.Run.Deadline // nolint:staticcheck
 	if deadlineValue != 0 && e.cfg.Run.Timeout == defaultTimeout {
 		e.cfg.Run.Timeout = deadlineValue
 	}

pkg/config/config.go

@@ -235,6 +235,7 @@ type LintersSettings struct {
 	Godot       GodotSettings
 	Testpackage TestpackageSettings
 	Nestif      NestifSettings
+	NoLintLint  NoLintLintSettings
 
 	Custom map[string]CustomLinterSettings
 }
@@ -316,6 +317,14 @@ type GodotSettings struct {
 	CheckAll bool `mapstructure:"check-all"`
 }
 
+type NoLintLintSettings struct {
+	RequireExplanation bool     `mapstructure:"require-explanation"`
+	AllowLeadingSpace  bool     `mapstructure:"allow-leading-space"`
+	RequireSpecific    bool     `mapstructure:"require-specific"`
+	AllowNoExplanation []string `mapstructure:"allow-no-explanation"`
+	AllowUnused        bool     `mapstructure:"allow-unused"`
+}
+
 type TestpackageSettings struct {
 	SkipRegexp string `mapstructure:"skip-regexp"`
 }
@@ -324,7 +333,6 @@ type NestifSettings struct {
 	MinComplexity int `mapstructure:"min-complexity"`
 }
 
-//nolint:gomnd
 var defaultLintersSettings = LintersSettings{
 	Lll: LllSettings{
 		LineLength: 120,
@@ -363,6 +371,12 @@ var defaultLintersSettings = LintersSettings{
 		ForceCuddleErrCheckAndAssign:     false,
 		ForceCaseTrailingWhitespaceLimit: 0,
 	},
+	NoLintLint: NoLintLintSettings{
+		RequireExplanation: false,
+		AllowLeadingSpace:  true,
+		RequireSpecific:    false,
+		AllowUnused:        false,
+	},
 	Testpackage: TestpackageSettings{
 		SkipRegexp: `(export|internal)_test\.go`,
 	},

pkg/golinters/deadcode.go

@@ -28,7 +28,7 @@ func NewDeadcode() *goanalysis.Linter {
 			}
 			res := make([]goanalysis.Issue, 0, len(issues))
 			for _, i := range issues {
-				res = append(res, goanalysis.NewIssue(&result.Issue{ //nolint:scopelint
+				res = append(res, goanalysis.NewIssue(&result.Issue{
 					Pos:        i.Pos,
 					Text:       fmt.Sprintf("%s is unused", formatCode(i.UnusedIdentName, nil)),
 					FromLinter: linterName,

pkg/golinters/depguard.go

@@ -94,7 +94,7 @@ func NewDepguard() *goanalysis.Linter {
 				if userSuppliedMsgSuffix != "" {
 					userSuppliedMsgSuffix = ": " + userSuppliedMsgSuffix
 				}
-				res = append(res, goanalysis.NewIssue(&result.Issue{ //nolint:scopelint
+				res = append(res, goanalysis.NewIssue(&result.Issue{
 					Pos:        i.Position,
 					Text:       fmt.Sprintf("%s %s%s", formatCode(i.PackageName, lintCtx.Cfg), msgSuffix, userSuppliedMsgSuffix),
 					FromLinter: linterName,

pkg/golinters/dupl.go

@@ -57,7 +57,7 @@ func NewDupl() *goanalysis.Linter {
 				text := fmt.Sprintf("%d-%d lines are duplicate of %s",
 					i.From.LineStart(), i.From.LineEnd(),
 					formatCode(dupl, lintCtx.Cfg))
-				res = append(res, goanalysis.NewIssue(&result.Issue{ //nolint:scopelint
+				res = append(res, goanalysis.NewIssue(&result.Issue{
 					Pos: token.Position{
 						Filename: i.From.Filename(),
 						Line:     i.From.LineStart(),

pkg/golinters/errcheck.go

@@ -59,7 +59,7 @@ func NewErrcheck() *goanalysis.Linter {
 				} else {
 					text = "Error return value is not checked"
 				}
-				issues = append(issues, goanalysis.NewIssue(&result.Issue{ //nolint:scopelint
+				issues = append(issues, goanalysis.NewIssue(&result.Issue{
 					FromLinter: linterName,
 					Text:       text,
 					Pos:        i.Pos,

pkg/golinters/funlen.go

@@ -42,7 +42,7 @@ func NewFunlen() *goanalysis.Linter {
 
 			res := make([]goanalysis.Issue, len(issues))
 			for k, i := range issues {
-				res[k] = goanalysis.NewIssue(&result.Issue{ //nolint:scopelint
+				res[k] = goanalysis.NewIssue(&result.Issue{
 					Pos: token.Position{
 						Filename: i.Pos.Filename,
 						Line:     i.Pos.Line,

pkg/golinters/goanalysis/issue.go

@@ -21,9 +21,11 @@ func NewIssue(i *result.Issue, pass *analysis.Pass) Issue {
 }
 
 type EncodingIssue struct {
-	FromLinter  string
-	Text        string
-	Pos         token.Position
-	LineRange   *result.Range
-	Replacement *result.Replacement
+	FromLinter           string
+	Text                 string
+	Pos                  token.Position
+	LineRange            *result.Range
+	Replacement          *result.Replacement
+	ExpectNoLint         bool
+	ExpectedNoLintLinter string
 }

pkg/golinters/goanalysis/linter.go

@@ -323,11 +323,13 @@ func saveIssuesToCache(allPkgs []*packages.Package, pkgsFromCache map[*packages.
 				for ind := range pkgIssues {
 					i := &pkgIssues[ind]
 					encodedIssues = append(encodedIssues, EncodingIssue{
-						FromLinter:  i.FromLinter,
-						Text:        i.Text,
-						Pos:         i.Pos,
-						LineRange:   i.LineRange,
-						Replacement: i.Replacement,
+						FromLinter:           i.FromLinter,
+						Text:                 i.Text,
+						Pos:                  i.Pos,
+						LineRange:            i.LineRange,
+						Replacement:          i.Replacement,
+						ExpectNoLint:         i.ExpectNoLint,
+						ExpectedNoLintLinter: i.ExpectedNoLintLinter,
 					})
 				}
 
@@ -392,12 +394,14 @@ func loadIssuesFromCache(pkgs []*packages.Package, lintCtx *linter.Context,
 				issues := make([]result.Issue, 0, len(pkgIssues))
 				for _, i := range pkgIssues {
 					issues = append(issues, result.Issue{
-						FromLinter:  i.FromLinter,
-						Text:        i.Text,
-						Pos:         i.Pos,
-						LineRange:   i.LineRange,
-						Replacement: i.Replacement,
-						Pkg:         pkg,
+						FromLinter:           i.FromLinter,
+						Text:                 i.Text,
+						Pos:                  i.Pos,
+						LineRange:            i.LineRange,
+						Replacement:          i.Replacement,
+						Pkg:                  pkg,
+						ExpectNoLint:         i.ExpectNoLint,
+						ExpectedNoLintLinter: i.ExpectedNoLintLinter,
 					})
 				}
 				cacheRes.issues = issues

pkg/golinters/goanalysis/runner.go

@@ -312,7 +312,7 @@ func (r *runner) analyze(pkgs []*packages.Package, analyzers []*analysis.Analyze
 	debugf("There are %d initial and %d total packages", len(initialPkgs), len(loadingPackages))
 	for _, lp := range loadingPackages {
 		if lp.isInitial {
-			wg.Add(1) //nolint:gomnd
+			wg.Add(1)
 			go func(lp *loadingPackage) {
 				lp.analyzeRecursive(r.loadMode, loadSem)
 				wg.Done()

pkg/golinters/gocognit.go

@@ -49,7 +49,7 @@ func NewGocognit() *goanalysis.Linter {
 					break // Break as the stats is already sorted from greatest to least
 				}
 
-				res = append(res, goanalysis.NewIssue(&result.Issue{ //nolint:scopelint
+				res = append(res, goanalysis.NewIssue(&result.Issue{
 					Pos: s.Pos,
 					Text: fmt.Sprintf("cognitive complexity %d of func %s is high (> %d)",
 						s.Complexity, formatCode(s.FuncName, lintCtx.Cfg), lintCtx.Settings().Gocognit.MinComplexity),

pkg/golinters/goconst.go

@@ -70,7 +70,7 @@ func checkConstants(pass *analysis.Pass, lintCtx *linter.Context) ([]goanalysis.
 		} else {
 			textEnd = fmt.Sprintf(", but such constant %s already exists", formatCode(i.MatchingConst, lintCtx.Cfg))
 		}
-		res = append(res, goanalysis.NewIssue(&result.Issue{ //nolint:scopelint
+		res = append(res, goanalysis.NewIssue(&result.Issue{
 			Pos:        i.Pos,
 			Text:       textBegin + textEnd,
 			FromLinter: goconstName,

pkg/golinters/gocyclo.go

@@ -49,7 +49,7 @@ func NewGocyclo() *goanalysis.Linter {
 					break // Break as the stats is already sorted from greatest to least
 				}
 
-				res = append(res, goanalysis.NewIssue(&result.Issue{ //nolint:scopelint
+				res = append(res, goanalysis.NewIssue(&result.Issue{
 					Pos: s.Pos,
 					Text: fmt.Sprintf("cyclomatic complexity %d of func %s is high (> %d)",
 						s.Complexity, formatCode(s.FuncName, lintCtx.Cfg), lintCtx.Settings().Gocyclo.MinComplexity),

pkg/golinters/godox.go

@@ -41,7 +41,7 @@ func NewGodox() *goanalysis.Linter {
 
 			res := make([]goanalysis.Issue, len(issues))
 			for k, i := range issues {
-				res[k] = goanalysis.NewIssue(&result.Issue{ //nolint:scopelint
+				res[k] = goanalysis.NewIssue(&result.Issue{
 					Pos: token.Position{
 						Filename: i.Pos.Filename,
 						Line:     i.Pos.Line,

pkg/golinters/gofmt_common.go

@@ -59,7 +59,6 @@ func (p *hunkChangesParser) parseDiffLines(h *diffpkg.Hunk) {
 
 		lineStr := string(line)
 
-		//nolint:gocritic
 		if strings.HasPrefix(lineStr, "-") {
 			dl.typ = diffLineDeleted
 			dl.data = strings.TrimPrefix(lineStr, "-")

pkg/golinters/gomodguard.go

@@ -73,7 +73,7 @@ func NewGomodguard() *goanalysis.Linter {
 			defer mu.Unlock()
 
 			for _, err := range gomodguardErrors {
-				issues = append(issues, goanalysis.NewIssue(&result.Issue{ //nolint:scopelint
+				issues = append(issues, goanalysis.NewIssue(&result.Issue{
 					FromLinter: gomodguardName,
 					Pos:        err.Position,
 					Text:       err.Reason,

pkg/golinters/gosec.go

@@ -73,7 +73,7 @@ func NewGosec() *goanalysis.Linter {
 					continue
 				}
 
-				res = append(res, goanalysis.NewIssue(&result.Issue{ //nolint:scopelint
+				res = append(res, goanalysis.NewIssue(&result.Issue{
 					Pos: token.Position{
 						Filename: i.File,
 						Line:     line,

pkg/golinters/ineffassign.go

@@ -42,7 +42,7 @@ func NewIneffassign() *goanalysis.Linter {
 
 			res := make([]goanalysis.Issue, 0, len(issues))
 			for _, i := range issues {
-				res = append(res, goanalysis.NewIssue(&result.Issue{ //nolint:scopelint
+				res = append(res, goanalysis.NewIssue(&result.Issue{
 					Pos:        i.Pos,
 					Text:       fmt.Sprintf("ineffectual assignment to %s", formatCode(i.IdentName, lintCtx.Cfg)),
 					FromLinter: ineffassignName,

pkg/golinters/interfacer.go

@@ -48,7 +48,7 @@ func NewInterfacer() *goanalysis.Linter {
 			res := make([]goanalysis.Issue, 0, len(issues))
 			for _, i := range issues {
 				pos := pass.Fset.Position(i.Pos())
-				res = append(res, goanalysis.NewIssue(&result.Issue{ //nolint:scopelint
+				res = append(res, goanalysis.NewIssue(&result.Issue{
 					Pos:        pos,
 					Text:       i.Message(),
 					FromLinter: interfacerName,

pkg/golinters/maligned.go

@@ -40,7 +40,7 @@ func NewMaligned() *goanalysis.Linter {
 				if lintCtx.Settings().Maligned.SuggestNewOrder {
 					text += fmt.Sprintf(":\n%s", formatCodeBlock(i.NewStructDef, lintCtx.Cfg))
 				}
-				issues = append(issues, goanalysis.NewIssue(&result.Issue{ //nolint:scopelint
+				issues = append(issues, goanalysis.NewIssue(&result.Issue{
 					Pos:        i.Pos,
 					Text:       text,
 					FromLinter: linterName,

pkg/golinters/nestif.go

@@ -46,7 +46,7 @@ func NewNestif() *goanalysis.Linter {
 
 			res := make([]goanalysis.Issue, 0, len(issues))
 			for _, i := range issues {
-				res = append(res, goanalysis.NewIssue(&result.Issue{ //nolint:scopelint
+				res = append(res, goanalysis.NewIssue(&result.Issue{
 					Pos:        i.Pos,
 					Text:       i.Message,
 					FromLinter: nestifName,