Errors() +performance : using strings.Builder instead of string concatenation

errors.go

@@ -21,7 +21,10 @@
 
 package battery
 
-import "fmt"
+import (
+	"fmt"
+	"strings"
+)
 
 // ErrNotFound variable represents battery not found error.
 //
@@ -130,6 +133,23 @@ func (e Errors) Error() string {
 	return s + "]"
 }
 
+func (e Errors) ErrorBuilder() string {
+	var s strings.Builder
+	s.WriteString("[")
+	for idx, err := range e {
+		if err != nil {
+			if idx == len(e)-1 {
+				s.Write([]byte(err.Error()))
+			} else {
+				s.WriteString(err.Error())
+				s.WriteString(" ")
+			}
+		}
+	}
+	s.WriteString("]")
+	return s.String()
+}
+
 func wrapError(err error) error {
 	if perr, ok := err.(ErrPartial); ok {
 		if perr.isNil() {

errors_test.go

@@ -76,3 +76,29 @@ func TestErrors(t *testing.T) {
 		}
 	}
 }
+
+func BenchmarkErrors_Error(b *testing.B) {
+	e := getErrors()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		_ = e.Error()
+	}
+}
+
+func BenchmarkErrors_ErrorBuilder(b *testing.B) {
+	e := getErrors()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		_ = e.ErrorBuilder()
+	}
+}
+
+func getErrors() Errors {
+	return Errors([]error{
+		errors.New("1"),
+		errors.New("2"),
+		errors.New("3"),
+		errors.New("4"),
+		errors.New("5"),
+	})
+}