chore: fix new issue detected by go-critic

.golangci.yml

@@ -117,6 +117,9 @@ linters:
   # - wsl
 
 issues:
+  exclude:
+    # disable this rule for go1.15 compatibility
+    - 'ioutilDeprecated:'
   # Excluding configuration per-path, per-linter, per-text and per-source
   exclude-rules:
     - path: _test\.go

pkg/golinters/goanalysis/runner_loadingpackage.go

@@ -492,6 +492,6 @@ func sizeOfReflectValueTreeBytes(rv reflect.Value, visitedPtrs map[uintptr]struc
 	case reflect.Invalid:
 		return 0
 	default:
-		panic("unknown rv of type " + fmt.Sprint(rv))
+		panic("unknown rv of type " + rv.String())
 	}
 }

pkg/golinters/gocritic.go

@@ -34,7 +34,7 @@ func NewGocritic() *goanalysis.Linter {
 	}
 	return goanalysis.NewLinter(
 		gocriticName,
-		`Provides many diagnostics that check for bugs, performance and style issues.
+		`Provides diagnostics that check for bugs, performance and style issues.
 Extensible without recompilation through dynamic rules.
 Dynamic rules are written declaratively with AST patterns, filters, report message and optional suggestion.`,
 		[]*analysis.Analyzer{analyzer},

pkg/result/issue.go

@@ -92,7 +92,7 @@ func (i *Issue) Fingerprint() string {
 	}
 
 	hash := md5.New() //nolint:gosec
-	_, _ = hash.Write([]byte(fmt.Sprintf("%s%s%s", i.Pos.Filename, i.Text, firstLine)))
+	_, _ = fmt.Fprintf(hash, "%s%s%s", i.Pos.Filename, i.Text, firstLine)
 
 	return fmt.Sprintf("%X", hash.Sum(nil))
 }

pkg/timeutils/stopwatch.go

@@ -15,10 +15,10 @@ const noStagesText = "no stages"
 type Stopwatch struct {
 	name      string
 	startedAt time.Time
-	stages    map[string]time.Duration
 	log       logutils.Log
 
-	sync.Mutex
+	stages map[string]time.Duration
+	mu     sync.Mutex
 }
 
 func NewStopwatch(name string, log logutils.Log) *Stopwatch {
@@ -110,7 +110,7 @@ func (s *Stopwatch) TrackStage(name string, f func()) {
 	startedAt := time.Now()
 	f()
 
-	s.Lock()
+	s.mu.Lock()
 	s.stages[name] += time.Since(startedAt)
-	s.Unlock()
+	s.mu.Unlock()
 }

scripts/expand_website_templates/main.go

@@ -136,7 +136,7 @@ func getLatestVersion() (string, error) {
 	req, err := http.NewRequest( // nolint:noctx
 		http.MethodGet,
 		"https://api.github.com/repos/golangci/golangci-lint/releases/latest",
-		nil,
+		http.NoBody,
 	)
 	if err != nil {
 		return "", fmt.Errorf("failed to prepare a http request: %s", err)
@@ -286,7 +286,7 @@ func check(b bool, title string) string {
 }
 
 func span(title, icon string) string {
-	return fmt.Sprintf(`<span title="%s">%s</span>`, title, icon)
+	return fmt.Sprintf(`<span title=%q>%s</span>`, title, icon)
 }
 
 func getThanksList() string {