Fix #96: support lll

Author: jirfag

Diff for: .golangci.example.yml

@@ -104,6 +104,9 @@ linters-settings:
     # Default is to use a neutral variety of English.
     # Setting locale to US will correct the British spelling of 'colour' to 'color'.
     locale: US
+  lll:
+    # max line length, lines longer will be reported. Default is 120. '\t' is counted as 1 character.
+    line-length: 120
 
 linters:
   enable:

Diff for: README.md

@@ -114,6 +114,7 @@ maligned: Tool to detect Go structs that would take less memory if their fields
 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]
+lll: Reports long lines [fast: true]
 ```
 
 Pass `-E/--enable` to enable linter and `-D/--disable` to disable:
@@ -220,6 +221,7 @@ golangci-lint linters
 - [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
+- [lll](https://github.com/walle/lll) - Reports long lines
 
 # Configuration
 The config file has lower priority than command-line options. If the same bool/string/int option is provided on the command-line
@@ -422,6 +424,9 @@ linters-settings:
     # Default is to use a neutral variety of English.
     # Setting locale to US will correct the British spelling of 'colour' to 'color'.
     locale: US
+  lll:
+    # max line length, lines longer will be reported. Default is 120. '\t' is counted as 1 character.
+    line-length: 120
 
 linters:
   enable:
@@ -601,6 +606,7 @@ Thanks to developers and authors of used linters:
 - [alecthomas](https://github.com/alecthomas)
 - [OpenPeeDeeP](https://github.com/OpenPeeDeeP)
 - [client9](https://github.com/client9)
+- [walle](https://github.com/walle)
 
 # Future Plans
 1. Upstream all changes of forked linters.

Diff for: pkg/commands/executor.go

@@ -23,7 +23,7 @@ type Executor struct {
 
 func NewExecutor(version, commit, date string) *Executor {
 	e := &Executor{
-		cfg:     &config.Config{},
+		cfg:     config.NewDefault(),
 		version: version,
 		commit:  commit,
 		date:    date,

Diff for: pkg/commands/run.go

@@ -32,7 +32,8 @@ func getDefaultExcludeHelp() string {
 	return strings.Join(parts, "\n")
 }
 
-const welcomeMessage = "Run this tool in cloud on every github pull request in https://golangci.com for free (public repos)"
+const welcomeMessage = "Run this tool in cloud on every github pull " +
+	"request in https://golangci.com for free (public repos)"
 
 func wh(text string) string {
 	return color.GreenString(text)
@@ -62,7 +63,8 @@ func initFlagSet(fs *pflag.FlagSet, cfg *config.Config) {
 	fs.StringSliceVar(&rc.BuildTags, "build-tags", nil, wh("Build tags"))
 	fs.DurationVar(&rc.Deadline, "deadline", time.Minute, wh("Deadline for total work"))
 	fs.BoolVar(&rc.AnalyzeTests, "tests", true, wh("Analyze tests (*_test.go)"))
-	fs.BoolVar(&rc.PrintResourcesUsage, "print-resources-usage", false, wh("Print avg and max memory usage of golangci-lint and total time"))
+	fs.BoolVar(&rc.PrintResourcesUsage, "print-resources-usage", false,
+		wh("Print avg and max memory usage of golangci-lint and total time"))
 	fs.StringVarP(&rc.Config, "config", "c", "", wh("Read config from file path `PATH`"))
 	fs.BoolVar(&rc.NoConfig, "no-config", false, wh("Don't read config"))
 	fs.StringSliceVar(&rc.SkipDirs, "skip-dirs", nil, wh("Regexps of directories to skip"))
@@ -75,16 +77,20 @@ func initFlagSet(fs *pflag.FlagSet, cfg *config.Config) {
 	// but when number of linters started to grow it became ovious that
 	// we can't fill 90% of flags by linters settings: common flags became hard to find.
 	// New linters settings should be done only through config file.
-	fs.BoolVar(&lsc.Errcheck.CheckTypeAssertions, "errcheck.check-type-assertions", false, "Errcheck: check for ignored type assertion results")
+	fs.BoolVar(&lsc.Errcheck.CheckTypeAssertions, "errcheck.check-type-assertions",
+		false, "Errcheck: check for ignored type assertion results")
 	hideFlag("errcheck.check-type-assertions")
 
-	fs.BoolVar(&lsc.Errcheck.CheckAssignToBlank, "errcheck.check-blank", false, "Errcheck: check for errors assigned to blank identifier: _ = errFunc()")
+	fs.BoolVar(&lsc.Errcheck.CheckAssignToBlank, "errcheck.check-blank", false,
+		"Errcheck: check for errors assigned to blank identifier: _ = errFunc()")
 	hideFlag("errcheck.check-blank")
 
-	fs.BoolVar(&lsc.Govet.CheckShadowing, "govet.check-shadowing", false, "Govet: check for shadowed variables")
+	fs.BoolVar(&lsc.Govet.CheckShadowing, "govet.check-shadowing", false,
+		"Govet: check for shadowed variables")
 	hideFlag("govet.check-shadowing")
 
-	fs.Float64Var(&lsc.Golint.MinConfidence, "golint.min-confidence", 0.8, "Golint: minimum confidence of a problem to print it")
+	fs.Float64Var(&lsc.Golint.MinConfidence, "golint.min-confidence", 0.8,
+		"Golint: minimum confidence of a problem to print it")
 	hideFlag("golint.min-confidence")
 
 	fs.BoolVar(&lsc.Gofmt.Simplify, "gofmt.simplify", true, "Gofmt: simplify code")
@@ -94,7 +100,8 @@ func initFlagSet(fs *pflag.FlagSet, cfg *config.Config) {
 		30, "Minimal complexity of function to report it")
 	hideFlag("gocyclo.min-complexity")
 
-	fs.BoolVar(&lsc.Maligned.SuggestNewOrder, "maligned.suggest-new", false, "Maligned: print suggested more optimal struct fields ordering")
+	fs.BoolVar(&lsc.Maligned.SuggestNewOrder, "maligned.suggest-new", false,
+		"Maligned: print suggested more optimal struct fields ordering")
 	hideFlag("maligned.suggest-new")
 
 	fs.IntVar(&lsc.Dupl.Threshold, "dupl.threshold",
@@ -124,21 +131,29 @@ func initFlagSet(fs *pflag.FlagSet, cfg *config.Config) {
 	fs.BoolVar(&lc.EnableAll, "enable-all", false, wh("Enable all linters"))
 	fs.BoolVar(&lc.DisableAll, "disable-all", false, wh("Disable all linters"))
 	fs.StringSliceVarP(&lc.Presets, "presets", "p", nil,
-		wh(fmt.Sprintf("Enable presets (%s) of linters. Run 'golangci-lint linters' to see them. This option implies option --disable-all", strings.Join(lintersdb.AllPresets(), "|"))))
+		wh(fmt.Sprintf("Enable presets (%s) of linters. Run 'golangci-lint linters' to see "+
+			"them. This option implies option --disable-all", strings.Join(lintersdb.AllPresets(), "|"))))
 	fs.BoolVar(&lc.Fast, "fast", false, wh("Run only fast linters from enabled linters set"))
 
 	// Issues config
 	ic := &cfg.Issues
 	fs.StringSliceVarP(&ic.ExcludePatterns, "exclude", "e", nil, wh("Exclude issue by regexp"))
 	fs.BoolVar(&ic.UseDefaultExcludes, "exclude-use-default", true, getDefaultExcludeHelp())
 
-	fs.IntVar(&ic.MaxIssuesPerLinter, "max-issues-per-linter", 50, wh("Maximum issues count per one linter. Set to 0 to disable"))
-	fs.IntVar(&ic.MaxSameIssues, "max-same-issues", 3, wh("Maximum count of issues with the same text. Set to 0 to disable"))
+	fs.IntVar(&ic.MaxIssuesPerLinter, "max-issues-per-linter", 50,
+		wh("Maximum issues count per one linter. Set to 0 to disable"))
+	fs.IntVar(&ic.MaxSameIssues, "max-same-issues", 3,
+		wh("Maximum count of issues with the same text. Set to 0 to disable"))
 
 	fs.BoolVarP(&ic.Diff, "new", "n", false,
-		wh("Show only new issues: if there are unstaged changes or untracked files, only those changes are analyzed, else only changes in HEAD~ are analyzed.\nIt's a super-useful option for integration of golangci-lint into existing large codebase.\nIt's not practical to fix all existing issues at the moment of integration: much better don't allow issues in new code"))
-	fs.StringVar(&ic.DiffFromRevision, "new-from-rev", "", wh("Show only new issues created after git revision `REV`"))
-	fs.StringVar(&ic.DiffPatchFilePath, "new-from-patch", "", wh("Show only new issues created in git patch with file path `PATH`"))
+		wh("Show only new issues: if there are unstaged changes or untracked files, only those changes "+
+			"are analyzed, else only changes in HEAD~ are analyzed.\nIt's a super-useful option for integration "+
+			"of golangci-lint into existing large codebase.\nIt's not practical to fix all existing issues at "+
+			"the moment of integration: much better don't allow issues in new code"))
+	fs.StringVar(&ic.DiffFromRevision, "new-from-rev", "",
+		wh("Show only new issues created after git revision `REV`"))
+	fs.StringVar(&ic.DiffPatchFilePath, "new-from-patch", "",
+		wh("Show only new issues created in git patch with file path `PATH`"))
 
 }
 

Diff for: pkg/config/config.go

@@ -30,14 +30,16 @@ type ExcludePattern struct {
 
 var DefaultExcludePatterns = []ExcludePattern{
 	{
-		Pattern: "Error return value of .((os\\.)?std(out|err)\\..*|.*Close|.*Flush|os\\.Remove(All)?|.*printf?|os\\.(Un)?Setenv). is not checked",
-		Linter:  "errcheck",
-		Why:     "Almost all programs ignore errors on these functions and in most cases it's ok",
+		Pattern: "Error return value of .((os\\.)?std(out|err)\\..*|.*Close" +
+			"|.*Flush|os\\.Remove(All)?|.*printf?|os\\.(Un)?Setenv). is not checked",
+		Linter: "errcheck",
+		Why:    "Almost all programs ignore errors on these functions and in most cases it's ok",
 	},
 	{
-		Pattern: "(comment on exported (method|function|type|const)|should have( a package)? comment|comment should be of the form)",
-		Linter:  "golint",
-		Why:     "Annoying issue about not having a comment. The rare codebase has such comments",
+		Pattern: "(comment on exported (method|function|type|const)|" +
+			"should have( a package)? comment|comment should be of the form)",
+		Linter: "golint",
+		Why:    "Annoying issue about not having a comment. The rare codebase has such comments",
 	},
 	{
 		Pattern: "func name will be used as test\\.Test.* by other packages, and that stutters; consider calling this",
@@ -156,6 +158,17 @@ type LintersSettings struct {
 	Misspell struct {
 		Locale string
 	}
+	Lll LllSettings
+}
+
+type LllSettings struct {
+	LineLength int `mapstructure:"line-length"`
+}
+
+var defaultLintersSettings = LintersSettings{
+	Lll: LllSettings{
+		LineLength: 120,
+	},
 }
 
 type Linters struct {
@@ -196,3 +209,9 @@ type Config struct { //nolint:maligned
 
 	InternalTest bool // Option is used only for testing golangci-lint code, don't use it
 }
+
+func NewDefault() *Config {
+	return &Config{
+		LintersSettings: defaultLintersSettings,
+	}
+}

Diff for: pkg/golinters/errcheck.go

@@ -16,7 +16,8 @@ func (Errcheck) Name() string {
 }
 
 func (Errcheck) Desc() string {
-	return "Errcheck is a program for checking for unchecked errors in go programs. These unchecked errors can be critical bugs in some cases"
+	return "Errcheck is a program for checking for unchecked errors " +
+		"in go programs. These unchecked errors can be critical bugs in some cases"
 }
 
 func (e Errcheck) Run(ctx context.Context, lintCtx *linter.Context) ([]result.Issue, error) {

Diff for: pkg/golinters/gofmt.go

@@ -31,7 +31,8 @@ func (g Gofmt) Desc() string {
 		return "Goimports does everything that gofmt does. Additionally it checks unused imports"
 	}
 
-	return "Gofmt checks whether code was gofmt-ed. By default this tool runs with -s option to check for code simplification"
+	return "Gofmt checks whether code was gofmt-ed. By default " +
+		"this tool runs with -s option to check for code simplification"
 }
 
 func getFirstDeletedAndAddedLineNumberInHunk(h *diff.Hunk) (int, int, error) {

Diff for: pkg/golinters/govet.go

@@ -25,7 +25,8 @@ func (Govet) Name() string {
 }
 
 func (Govet) Desc() string {
-	return "Vet examines Go source code and reports suspicious constructs, such as Printf calls whose arguments do not align with the format string"
+	return "Vet examines Go source code and reports suspicious constructs, " +
+		"such as Printf calls whose arguments do not align with the format string"
 }
 
 func (g Govet) Run(ctx context.Context, lintCtx *linter.Context) ([]result.Issue, error) {

Diff for: pkg/golinters/lll.go

@@ -0,0 +1,72 @@
+package golinters
+
+import (
+	"bufio"
+	"context"
+	"fmt"
+	"go/token"
+	"os"
+	"strings"
+	"unicode/utf8"
+
+	"github.com/golangci/golangci-lint/pkg/lint/linter"
+	"github.com/golangci/golangci-lint/pkg/result"
+)
+
+type Lll struct{}
+
+func (Lll) Name() string {
+	return "lll"
+}
+
+func (Lll) Desc() string {
+	return "Reports long lines"
+}
+
+func (lint Lll) getIssuesForFile(filename string, maxLineLen int) ([]result.Issue, error) {
+	var res []result.Issue
+
+	f, err := os.Open(filename)
+	if err != nil {
+		return nil, fmt.Errorf("can't open file %s: %s", filename, err)
+	}
+
+	lineNumber := 1
+	scanner := bufio.NewScanner(f)
+	for scanner.Scan() {
+		line := scanner.Text()
+		line = strings.Replace(line, "\t", " ", -1)
+		lineLen := utf8.RuneCountInString(line)
+		if lineLen > maxLineLen {
+			res = append(res, result.Issue{
+				Pos: token.Position{
+					Filename: filename,
+					Line:     lineNumber,
+					Column:   1,
+				},
+				Text:       fmt.Sprintf("line is %d characters", lineLen),
+				FromLinter: lint.Name(),
+			})
+		}
+		lineNumber++
+	}
+
+	if err := scanner.Err(); err != nil {
+		return nil, fmt.Errorf("can't scan file %s: %s", filename, err)
+	}
+
+	return res, nil
+}
+
+func (lint Lll) Run(ctx context.Context, lintCtx *linter.Context) ([]result.Issue, error) {
+	var res []result.Issue
+	for _, f := range lintCtx.PkgProgram.Files(lintCtx.Cfg.Run.AnalyzeTests) {
+		issues, err := lint.getIssuesForFile(f, lintCtx.Settings().Lll.LineLength)
+		if err != nil {
+			return nil, err
+		}
+		res = append(res, issues...)
+	}
+
+	return res, nil
+}

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

@@ -14,7 +14,8 @@ import (
 )
 
 func AllPresets() []string {
-	return []string{linter.PresetBugs, linter.PresetUnused, linter.PresetFormatting, linter.PresetStyle, linter.PresetComplexity, linter.PresetPerformance}
+	return []string{linter.PresetBugs, linter.PresetUnused, linter.PresetFormatting,
+		linter.PresetStyle, linter.PresetComplexity, linter.PresetPerformance}
 }
 
 func allPresetsSet() map[string]bool {
@@ -166,6 +167,10 @@ func GetAllSupportedLinterConfigs() []linter.Config {
 			WithPresets(linter.PresetStyle).
 			WithSpeed(7).
 			WithURL("https://github.com/client9/misspell"),
+		linter.NewConfig(golinters.Lll{}).
+			WithPresets(linter.PresetStyle).
+			WithSpeed(10).
+			WithURL("https://github.com/walle/lll"),
 	}
 
 	if os.Getenv("GOLANGCI_COM_RUN") == "1" {
@@ -175,6 +180,7 @@ func GetAllSupportedLinterConfigs() []linter.Config {
 			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
+			golinters.Lll{}.Name():       true, // annoying
 		}
 		return enableLinterConfigs(lcs, func(lc *linter.Config) bool {
 			return !disabled[lc.Linter.Name()]
@@ -314,7 +320,10 @@ func GetAllLinterConfigsForPreset(p string) []linter.Config {
 	return ret
 }
 
-func getEnabledLintersSet(lcfg *config.Linters, enabledByDefaultLinters []linter.Config) map[string]*linter.Config { // nolint:gocyclo
+// nolint:gocyclo
+func getEnabledLintersSet(lcfg *config.Linters,
+	enabledByDefaultLinters []linter.Config) map[string]*linter.Config {
+
 	resultLintersSet := map[string]*linter.Config{}
 	switch {
 	case len(lcfg.Presets) != 0:

Diff for: pkg/lint/load.go

@@ -109,7 +109,9 @@ func isLocalProjectAnalysis(args []string) bool {
 	return true
 }
 
-func getTypeCheckFuncBodies(cfg *config.Run, linters []linter.Config, pkgProg *packages.Program, log logutils.Log) func(string) bool {
+func getTypeCheckFuncBodies(cfg *config.Run, linters []linter.Config,
+	pkgProg *packages.Program, log logutils.Log) func(string) bool {
+
 	if !isLocalProjectAnalysis(cfg.Args) {
 		loadDebugf("analysis in nonlocal, don't optimize loading by not typechecking func bodies")
 		return nil
@@ -155,7 +157,9 @@ func getTypeCheckFuncBodies(cfg *config.Run, linters []linter.Config, pkgProg *p
 	}
 }
 
-func loadWholeAppIfNeeded(ctx context.Context, linters []linter.Config, cfg *config.Config, pkgProg *packages.Program, log logutils.Log) (*loader.Program, *loader.Config, error) {
+func loadWholeAppIfNeeded(ctx context.Context, linters []linter.Config, cfg *config.Config,
+	pkgProg *packages.Program, log logutils.Log) (*loader.Program, *loader.Config, error) {
+
 	if !isFullImportNeeded(linters, cfg) {
 		return nil, nil, nil
 	}
@@ -255,7 +259,9 @@ func separateNotCompilingPackages(lintCtx *linter.Context) {
 }
 
 //nolint:gocyclo
-func LoadContext(ctx context.Context, linters []linter.Config, cfg *config.Config, log logutils.Log) (*linter.Context, error) {
+func LoadContext(ctx context.Context, linters []linter.Config, cfg *config.Config,
+	log logutils.Log) (*linter.Context, error) {
+
 	// Set GOROOT to have working cross-compilation: cross-compiled binaries
 	// have invalid GOROOT. XXX: can't use runtime.GOROOT().
 	goroot, err := goutils.DiscoverGoRoot()

Diff for: pkg/lint/runner.go

@@ -66,7 +66,9 @@ type lintRes struct {
 	issues []result.Issue
 }
 
-func (r Runner) runLinterSafe(ctx context.Context, lintCtx *linter.Context, lc linter.Config) (ret []result.Issue, err error) {
+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 occurred: %s", panicData)
@@ -88,7 +90,9 @@ func (r Runner) runLinterSafe(ctx context.Context, lintCtx *linter.Context, lc l
 	return issues, nil
 }
 
-func (r Runner) runWorker(ctx context.Context, lintCtx *linter.Context, tasksCh <-chan linter.Config, lintResultsCh chan<- lintRes, name string) {
+func (r Runner) runWorker(ctx context.Context, lintCtx *linter.Context,
+	tasksCh <-chan linter.Config, lintResultsCh chan<- lintRes, name string) {
+
 	sw := timeutils.NewStopwatch(name, r.Log)
 	defer sw.Print()