"//nolint:nit" directive support

It allows skipping a whole file that includes the following line:

//nolint:nit

This is useful for allowing some tools to properly work, for example
go-swagger, to generate code not using grouped types.

break_comments.go

@@ -13,26 +13,33 @@ type (
  index int
  comments []int
  generatedFile bool
+ nolintNit bool
  }
 )
 
 const (
  breakComment = "//-"
  generatedFile = `^// Code generated .* DO NOT EDIT\.$`
+ nitLinter = "^//nolint:nit$"
 )
 
 // NewBreakComments returns all the valid break-like comments.
 func NewBreakComments(fset *token.FileSet, comments []*ast.CommentGroup) *BreakComments {
  r := BreakComments{}
 
- re, _ := regexp.Compile(generatedFile)
+ regen, _ := regexp.Compile(generatedFile)
+ renit, _ := regexp.Compile(nitLinter)
 
  for _, c := range comments {
  for _, c1 := range c.List {
- if re.MatchString(c1.Text) {
+ if regen.MatchString(c1.Text) {
  r.generatedFile = true
  }
 
+ if renit.MatchString(c1.Text) {
+ r.nolintNit = true
+ }
+
  if strings.HasPrefix(c1.Text, breakComment) {
  position := fset.PositionFor(c1.Pos(), false)
  if position.Column == 1 || position.Column == 2 { // left most either nested or not nested group declarations
@@ -51,6 +58,12 @@ func (c *BreakComments) HasGeneratedCode() bool {
  return c.generatedFile
 }
 
+// HasNoLintNit indicates whether the current file contains a "do not lint nit"
+// expression.
+func (c *BreakComments) HasNoLintNit() bool {
+ return c.nolintNit
+}
+
 // Moves current line cursor to the received line.
 func (c *BreakComments) MoveTo(line int) {
  if c.index >= len(c.comments) {

break_comments_test.go

@@ -9,23 +9,31 @@ import (
 )
 
 func TestBreakComments(t *testing.T) {
+ type expected struct {
+ result []int
+ generatedCode bool
+ noLintNit bool
+ }
+
  tests := [...]struct {
- name string
- filename string
- expected []int
- expectedCodegenerated bool
+ name string
+ filename string
+ expected expected
  }{
  {
  "OK",
  "break_comments1.go",
- []int{8, 13, 19},
- false,
+ expected{result: []int{8, 13, 19}},
  },
  {
  "OK: code generated",
  "break_comments2.go",
- nil,
- true,
+ expected{generatedCode: true},
+ },
+ {
+ "OK: nolint nit",
+ "break_comments3.go",
+ expected{noLintNit: true},
  },
  }
 
@@ -36,7 +44,7 @@ func TestBreakComments(t *testing.T) {
  var actual []int
 
  bc := nit.NewBreakComments(fset, f.Comments)
- for _, v := range tt.expected {
+ for _, v := range tt.expected.result {
  bc.MoveTo(v)
  v = bc.Next()
  if v == -1 {
@@ -45,11 +53,16 @@ func TestBreakComments(t *testing.T) {
  actual = append(actual, v)
  }
 
- if !cmp.Equal(tt.expected, actual) {
+ if !cmp.Equal(tt.expected.result, actual) {
  ts.Errorf("expected values do not match: %s", cmp.Diff(tt.expected, actual))
  }
- if tt.expectedCodegenerated != bc.HasGeneratedCode() {
- ts.Errorf("expected %t, got %t", tt.expectedCodegenerated, bc.HasGeneratedCode())
+
+ if tt.expected.generatedCode != bc.HasGeneratedCode() {
+ ts.Errorf("expected %t, got %t", tt.expected.generatedCode, bc.HasGeneratedCode())
+ }
+
+ if tt.expected.noLintNit != bc.HasNoLintNit() {
+ ts.Errorf("expected %t, got %t", tt.expected.noLintNit, bc.HasNoLintNit())
  }
  })
  }

cmd/nit/main.go

@@ -30,6 +30,7 @@ func main() {
 
  localPkg := flag.String("pkg", "", "local package")
  skipGenerated := flag.Bool("skip-generated", false, "skip generated files")
+ nolint := flag.Bool("nolint", false, "enable nolint directive")
  includeTests := flag.Bool("include-tests", false, "include test files")
  showVersion := flag.Bool("version", false, "prints current version information")
 
@@ -57,6 +58,7 @@ func main() {
  v := nit.Nitpicker{
  LocalPath: *localPkg,
  SkipGeneratedFile: *skipGenerated,
+ NoLint: *nolint,
  }
 
  if err := v.Validate(f); err != nil {

nitpicking.go

@@ -13,6 +13,7 @@ type (
  Nitpicker struct {
  LocalPath string
  SkipGeneratedFile bool
+ NoLint bool
  //-
  fset *token.FileSet
  fsm *FileSectionMachine
@@ -37,6 +38,10 @@ func (v *Nitpicker) Validate(filename string) error {
  return nil
  }
 
+ if v.comments.HasNoLintNit() && v.NoLint {
+ return nil
+ }
+
  for _, s := range f.Decls {
  if err := v.validateToken(s); err != nil {
  return err

testdata/break_comments3.go

@@ -0,0 +1,9 @@
+package testdata
+
+func NewBreakCommentType3() {}
+
+//nolint:nit
+
+type BreakCommentType3_1 int
+
+//-