chore: enable errorlint linter (#742)

Signed-off-by: Matthieu MOREL <matthieu.morel35@gmail.com>

Author: mmorel-35

.golangci.yml

@@ -1,6 +1,7 @@
 version: "2"
 linters:
   enable:
+    - errorlint
     - forbidigo
     - godot
     - misspell

blockdevice/stats_test.go

@@ -14,6 +14,7 @@
 package blockdevice
 
 import (
+	"errors"
 	"os"
 	"reflect"
 	"testing"
@@ -181,9 +182,10 @@ func TestBlockDmInfo(t *testing.T) {
 
 	dm1Info, err := blockdevice.SysBlockDeviceMapperInfo(devices[1])
 	if err != nil {
-		if _, ok := err.(*os.PathError); ok {
+		var pErr *os.PathError
+		if errors.As(err, &pErr) {
 			// Fail the test if there's an error other than PathError.
-			if !os.IsNotExist(err) {
+			if !os.IsNotExist(pErr) {
 				t.Fatal(err)
 			}
 		} else {

proc.go

@@ -49,7 +49,7 @@ func (p Procs) Less(i, j int) bool { return p[i].PID < p[j].PID }
 // Self returns a process for the current process read via /proc/self.
 func Self() (Proc, error) {
 	fs, err := NewFS(DefaultMountPoint)
-	if err != nil || errors.Unwrap(err) == ErrMountPoint {
+	if err != nil || errors.Is(err, ErrMountPoint) {
 		return Proc{}, err
 	}
 	return fs.Self()

stat.go

@@ -16,6 +16,7 @@ package procfs
 import (
 	"bufio"
 	"bytes"
+	"errors"
 	"fmt"
 	"io"
 	"strconv"
@@ -92,7 +93,7 @@ func parseCPUStat(line string) (CPUStat, int64, error) {
 		&cpuStat.Iowait, &cpuStat.IRQ, &cpuStat.SoftIRQ, &cpuStat.Steal,
 		&cpuStat.Guest, &cpuStat.GuestNice)
 
-	if err != nil && err != io.EOF {
+	if err != nil && !errors.Is(err, io.EOF) {
 		return CPUStat{}, -1, fmt.Errorf("%w: couldn't parse %q (cpu): %w", ErrFileParse, line, err)
 	}
 	if count == 0 {

sysfs/net_class_aer.go

@@ -154,7 +154,7 @@ func parseCorrectableAerCounters(devicePath string, counters *CorrectableAerCoun
 		counterName := fields[0]
 		value, err := strconv.ParseUint(fields[1], 10, 64)
 		if err != nil {
-			return fmt.Errorf("error parsing value for %s: %v", counterName, err)
+			return fmt.Errorf("error parsing value for %s: %w", counterName, err)
 		}
 
 		switch counterName {
@@ -206,7 +206,7 @@ func parseUncorrectableAerCounters(devicePath string, counterType string,
 		counterName := fields[0]
 		value, err := strconv.ParseUint(fields[1], 10, 64)
 		if err != nil {
-			return fmt.Errorf("error parsing value for %s: %v", counterName, err)
+			return fmt.Errorf("error parsing value for %s: %w", counterName, err)
 		}
 
 		switch counterName {

sysfs/system_cpu_test.go

@@ -225,7 +225,7 @@ func TestIsolatedParsingCPU(t *testing.T) {
 			if err != nil && params.err != nil && err.Error() != params.err.Error() {
 				t.Fatalf("should have '%v' error: got '%v'", params.err, err)
 			}
-			if (err == nil || params.err == nil) && err != params.err {
+			if (err == nil || params.err == nil) && !errors.Is(err, params.err) {
 				t.Fatalf("should have %v error: got %v", params.err, err)
 			}