Fix #100: misspell linter support

Author: jirfag

Diff for: .golangci.example.yml

@@ -99,6 +99,11 @@ linters-settings:
     include-go-root: false
     packages:
       - github.com/davecgh/go-spew/spew
+  misspell:
+    # Correct spellings using locale preferences for US or UK.
+    # Default is to use a neutral variety of English.
+    # Setting locale to US will correct the British spelling of 'colour' to 'color'.
+    locale: US
 
 linters:
   enable:

Diff for: .golangci.yml

@@ -18,6 +18,8 @@ linters-settings:
       # logging is allowed only by logutils.Log, logrus
       # is allowed to use only in logutils package
       - github.com/sirupsen/logrus
+  misspell:
+    locale: US
 
 linters:
   enable-all: true

Diff for: Gopkg.lock

@@ -4,6 +4,9 @@ test:
 	GL_TEST_RUN=1 golangci-lint run --no-config -v
 	GL_TEST_RUN=1 go test -v ./...
 
+test_linters:
+	GL_TEST_RUN=1 go test -v ./test -count 1 -run TestSourcesFromTestdataWithIssuesDir/$T
+
 assets:
 	svg-term --cast=183662 --out docs/demo.svg --window --width 110 --height 30 --from 2000 --to 20000 --profile Dracula --term iterm2
 

Diff for: Makefile

@@ -113,6 +113,7 @@ goimports: Goimports does everything that gofmt does. Additionally it checks unu
 maligned: Tool to detect Go structs that would take less memory if their fields were sorted [fast: false]
 megacheck: 3 sub-linters in one: unused, gosimple and staticcheck [fast: false]
 depguard: Go linter that checks if package imports are in a list of acceptable packages [fast: false]
+misspell: Finds commonly misspelled English words in comments [fast: true]
 ```
 
 Pass `-E/--enable` to enable linter and `-D/--disable` to disable:
@@ -218,6 +219,7 @@ golangci-lint linters
 - [maligned](https://github.com/mdempsky/maligned) - Tool to detect Go structs that would take less memory if their fields were sorted
 - [megacheck](https://github.com/dominikh/go-tools/tree/master/cmd/megacheck) - 3 sub-linters in one: unused, gosimple and staticcheck
 - [depguard](https://github.com/OpenPeeDeeP/depguard) - Go linter that checks if package imports are in a list of acceptable packages
+- [misspell](https://github.com/client9/misspell) - Finds commonly misspelled English words in comments
 
 # Configuration
 The config file has lower priority than command-line options. If the same bool/string/int option is provided on the command-line
@@ -415,6 +417,11 @@ linters-settings:
     include-go-root: false
     packages:
       - github.com/davecgh/go-spew/spew
+  misspell:
+    # Correct spellings using locale preferences for US or UK.
+    # Default is to use a neutral variety of English.
+    # Setting locale to US will correct the British spelling of 'colour' to 'color'.
+    locale: US
 
 linters:
   enable:
@@ -487,6 +494,8 @@ linters-settings:
       # logging is allowed only by logutils.Log, logrus
       # is allowed to use only in logutils package
       - github.com/sirupsen/logrus
+  misspell:
+    locale: US
 
 linters:
   enable-all: true
@@ -591,6 +600,7 @@ Thanks to developers and authors of used linters:
 - [remyoudompheng](https://github.com/remyoudompheng)
 - [alecthomas](https://github.com/alecthomas)
 - [OpenPeeDeeP](https://github.com/OpenPeeDeeP)
+- [client9](https://github.com/client9)
 
 # Future Plans
 1. Upstream all changes of forked linters.

Diff for: README.md

@@ -153,6 +153,9 @@ type LintersSettings struct {
 		Packages      []string
 		IncludeGoRoot bool `mapstructure:"include-go-root"`
 	}
+	Misspell struct {
+		Locale string
+	}
 }
 
 type Linters struct {

Diff for: pkg/config/config.go

@@ -0,0 +1,69 @@
+package golinters
+
+import (
+	"context"
+	"fmt"
+	"go/token"
+	"io/ioutil"
+	"strings"
+
+	"github.com/client9/misspell"
+	"github.com/golangci/golangci-lint/pkg/lint/linter"
+	"github.com/golangci/golangci-lint/pkg/result"
+)
+
+type Misspell struct{}
+
+func (Misspell) Name() string {
+	return "misspell"
+}
+
+func (Misspell) Desc() string {
+	return "Finds commonly misspelled English words in comments"
+}
+
+func (lint Misspell) Run(ctx context.Context, lintCtx *linter.Context) ([]result.Issue, error) {
+	r := misspell.Replacer{
+		Replacements: misspell.DictMain,
+	}
+
+	// Figure out regional variations
+	locale := lintCtx.Settings().Misspell.Locale
+	switch strings.ToUpper(locale) {
+	case "":
+		// nothing
+	case "US":
+		r.AddRuleList(misspell.DictAmerican)
+	case "UK", "GB":
+		r.AddRuleList(misspell.DictBritish)
+	case "NZ", "AU", "CA":
+		return nil, fmt.Errorf("unknown locale: %q", locale)
+	}
+
+	r.Compile()
+
+	var res []result.Issue
+	for _, f := range lintCtx.PkgProgram.Files(lintCtx.Cfg.Run.AnalyzeTests) {
+		fileContent, err := ioutil.ReadFile(f)
+		if err != nil {
+			return nil, fmt.Errorf("can't read file %s: %s", f, err)
+		}
+
+		_, diffs := r.ReplaceGo(string(fileContent))
+		for _, diff := range diffs {
+			text := fmt.Sprintf("`%s` is a misspelling of `%s`", diff.Original, diff.Corrected)
+			pos := token.Position{
+				Filename: f,
+				Line:     diff.Line,
+				Column:   diff.Column + 1,
+			}
+			res = append(res, result.Issue{
+				Pos:        pos,
+				Text:       text,
+				FromLinter: lint.Name(),
+			})
+		}
+	}
+
+	return res, nil
+}

Diff for: pkg/golinters/misspell.go

@@ -162,6 +162,10 @@ func GetAllSupportedLinterConfigs() []linter.Config {
 			WithPresets(linter.PresetStyle).
 			WithSpeed(6).
 			WithURL("https://github.com/OpenPeeDeeP/depguard"),
+		linter.NewConfig(golinters.Misspell{}).
+			WithPresets(linter.PresetStyle).
+			WithSpeed(7).
+			WithURL("https://github.com/client9/misspell"),
 	}
 
 	if os.Getenv("GOLANGCI_COM_RUN") == "1" {
@@ -170,6 +174,7 @@ func GetAllSupportedLinterConfigs() []linter.Config {
 			golinters.Dupl{}.Name():      true, // annoying
 			golinters.Maligned{}.Name():  true, // rarely usable
 			golinters.TypeCheck{}.Name(): true, // annoying because of different building envs
+			golinters.Misspell{}.Name():  true, // unsure about false-positives number
 		}
 		return enableLinterConfigs(lcs, func(lc *linter.Config) bool {
 			return !disabled[lc.Linter.Name()]

Diff for: pkg/lint/lintersdb/lintersdb.go

@@ -69,7 +69,7 @@ type lintRes struct {
 func (r Runner) runLinterSafe(ctx context.Context, lintCtx *linter.Context, lc linter.Config) (ret []result.Issue, err error) {
 	defer func() {
 		if panicData := recover(); panicData != nil {
-			err = fmt.Errorf("panic occured: %s", panicData)
+			err = fmt.Errorf("panic occurred: %s", panicData)
 			r.Log.Warnf("Panic stack trace: %s", debug.Stack())
 		}
 	}()
@@ -240,7 +240,7 @@ func (r Runner) Run(ctx context.Context, linters []linter.Config, lintCtx *linte
 	lintResultsCh := r.runWorkers(ctx, lintCtx, linters)
 	processedLintResultsCh := r.processLintResults(ctx, lintResultsCh)
 	if ctx.Err() != nil {
-		// XXX: always process issues, even if timeout occured
+		// XXX: always process issues, even if timeout occurred
 		finishedLintersN := 0
 		for range processedLintResultsCh {
 			finishedLintersN++

Diff for: pkg/lint/runner.go

@@ -21,7 +21,7 @@ const (
 	LogLevelInfo LogLevel = 1
 
 	// hidden errors: non critical errors: work can be continued, no need to fail whole program;
-	// tests will crash if any warning occured.
+	// tests will crash if any warning occurred.
 	LogLevelWarn LogLevel = 2
 
 	// only not hidden from user errors: whole program failing, usually

Diff for: pkg/logutils/log.go

@@ -3,6 +3,8 @@ package packages
 import (
 	"go/build"
 	"path/filepath"
+
+	"github.com/golangci/golangci-lint/pkg/result/processors"
 )
 
 type Package struct {
@@ -13,7 +15,13 @@ type Package struct {
 }
 
 func (pkg *Package) Files(includeTest bool) []string {
-	pkgFiles := append([]string{}, pkg.bp.GoFiles...)
+	var pkgFiles []string
+	for _, f := range pkg.bp.GoFiles {
+		if !processors.IsCgoFilename(f) {
+			// skip cgo at all levels to prevent failures on file reading
+			pkgFiles = append(pkgFiles, f)
+		}
+	}
 
 	// TODO: add cgo files
 	if includeTest {

Diff for: pkg/packages/package.go

@@ -1,8 +1,6 @@
 package processors
 
 import (
-	"strings"
-
 	"github.com/golangci/golangci-lint/pkg/result"
 )
 
@@ -23,7 +21,7 @@ func (p Cgo) Process(issues []result.Issue) ([]result.Issue, error) {
 	return filterIssues(issues, func(i *result.Issue) bool {
 		// some linters (.e.g gas, deadcode) return incorrect filepaths for cgo issues,
 		// it breaks next processing, so skip them
-		return i.FilePath() != "C" && !strings.HasSuffix(i.FilePath(), "/C")
+		return !IsCgoFilename(i.FilePath())
 	}), nil
 }
 

Diff for: pkg/result/processors/cgo.go

@@ -2,6 +2,7 @@ package processors
 
 import (
 	"fmt"
+	"strings"
 
 	"github.com/golangci/golangci-lint/pkg/result"
 )
@@ -44,3 +45,7 @@ func transformIssues(issues []result.Issue, transform func(i *result.Issue) *res
 
 	return retIssues
 }
+
+func IsCgoFilename(f string) bool {
+	return f == "C" || strings.HasSuffix(f, "/C")
+}

Diff for: pkg/result/processors/utils.go

@@ -34,7 +34,7 @@ func testSourcesFromDir(t *testing.T, dir string) {
 
 	for _, s := range sources {
 		s := s
-		t.Run(s, func(t *testing.T) {
+		t.Run(filepath.Base(s), func(t *testing.T) {
 			t.Parallel()
 			testOneSource(t, s)
 		})

Diff for: test/linters_test.go

@@ -0,0 +1,6 @@
+// args: -Emisspell
+package testdata
+
+func Misspell() {
+	// comment with incorrect spelling: occured // ERROR "`occured` is a misspelling of `occurred`"
+}