Sync with prometheus: enable errorf rule from perfsprint linter

.golangci.yml

@@ -111,7 +111,7 @@ linters-settings:
     extra-rules: true
   perfsprint:
      # Optimizes `fmt.Errorf`.
-    errorf: false
+    errorf: true
   revive:
     # By default, revive will enable only the linting rules that are named in the configuration file.
     # So, it's needed to explicitly enable all required rules here.

cmd/promtool/analyze.go

@@ -34,8 +34,8 @@ import (
 )
 
 var (
-	errNotNativeHistogram = fmt.Errorf("not a native histogram")
-	errNotEnoughData      = fmt.Errorf("not enough data")
+	errNotNativeHistogram = errors.New("not a native histogram")
+	errNotEnoughData      = errors.New("not enough data")
 
 	outputHeader = `Bucket stats for each histogram series over time
 ------------------------------------------------
@@ -169,7 +169,7 @@ func querySamples(ctx context.Context, api v1.API, query string, end time.Time)
 
 	matrix, ok := values.(model.Matrix)
 	if !ok {
-		return nil, fmt.Errorf("query of buckets resulted in non-Matrix")
+		return nil, errors.New("query of buckets resulted in non-Matrix")
 	}
 
 	return matrix, nil
@@ -259,7 +259,7 @@ func getBucketCountsAtTime(matrix model.Matrix, numBuckets, timeIdx int) ([]int,
 		prev := matrix[i].Values[timeIdx]
 		// Assume the results are nicely aligned.
 		if curr.Timestamp != prev.Timestamp {
-			return counts, fmt.Errorf("matrix result is not time aligned")
+			return counts, errors.New("matrix result is not time aligned")
 		}
 		counts[i+1] = int(curr.Value - prev.Value)
 	}

cmd/promtool/backfill.go

@@ -49,7 +49,7 @@ func getMinAndMaxTimestamps(p textparse.Parser) (int64, int64, error) {
 
 		_, ts, _ := p.Series()
 		if ts == nil {
-			return 0, 0, fmt.Errorf("expected timestamp for series got none")
+			return 0, 0, errors.New("expected timestamp for series got none")
 		}
 
 		if *ts > maxt {

cmd/promtool/main.go

@@ -444,7 +444,7 @@ func checkExperimental(f bool) {
 	}
 }
 
-var errLint = fmt.Errorf("lint error")
+var errLint = errors.New("lint error")
 
 type lintConfig struct {
 	all            bool

cmd/promtool/tsdb.go

@@ -662,7 +662,7 @@ func analyzeCompaction(ctx context.Context, block tsdb.BlockReader, indexr tsdb.
 				histogramChunkSize = append(histogramChunkSize, len(chk.Bytes()))
 				fhchk, ok := chk.(*chunkenc.FloatHistogramChunk)
 				if !ok {
-					return fmt.Errorf("chunk is not FloatHistogramChunk")
+					return errors.New("chunk is not FloatHistogramChunk")
 				}
 				it := fhchk.Iterator(nil)
 				bucketCount := 0
@@ -677,7 +677,7 @@ func analyzeCompaction(ctx context.Context, block tsdb.BlockReader, indexr tsdb.
 				histogramChunkSize = append(histogramChunkSize, len(chk.Bytes()))
 				hchk, ok := chk.(*chunkenc.HistogramChunk)
 				if !ok {
-					return fmt.Errorf("chunk is not HistogramChunk")
+					return errors.New("chunk is not HistogramChunk")
 				}
 				it := hchk.Iterator(nil)
 				bucketCount := 0

config/config.go

@@ -1072,7 +1072,7 @@ func (c *AlertmanagerConfig) UnmarshalYAML(unmarshal func(interface{}) error) er
 		c.HTTPClientConfig.Authorization != nil || c.HTTPClientConfig.OAuth2 != nil
 
 	if httpClientConfigAuthEnabled && c.SigV4Config != nil {
-		return fmt.Errorf("at most one of basic_auth, authorization, oauth2, & sigv4 must be configured")
+		return errors.New("at most one of basic_auth, authorization, oauth2, & sigv4 must be configured")
 	}
 
 	// Check for users putting URLs in target groups.
@@ -1420,7 +1420,7 @@ func (c *OTLPConfig) UnmarshalYAML(unmarshal func(interface{}) error) error {
 	for i, attr := range c.PromoteResourceAttributes {
 		attr = strings.TrimSpace(attr)
 		if attr == "" {
-			err = errors.Join(err, fmt.Errorf("empty promoted OTel resource attribute"))
+			err = errors.Join(err, errors.New("empty promoted OTel resource attribute"))
 			continue
 		}
 		if _, exists := seen[attr]; exists {

discovery/aws/ec2.go

@@ -161,7 +161,7 @@ type EC2Discovery struct {
 func NewEC2Discovery(conf *EC2SDConfig, logger *slog.Logger, metrics discovery.DiscovererMetrics) (*EC2Discovery, error) {
 	m, ok := metrics.(*ec2Metrics)
 	if !ok {
-		return nil, fmt.Errorf("invalid discovery metrics type")
+		return nil, errors.New("invalid discovery metrics type")
 	}
 
 	if logger == nil {

discovery/aws/lightsail.go

@@ -134,7 +134,7 @@ type LightsailDiscovery struct {
 func NewLightsailDiscovery(conf *LightsailSDConfig, logger *slog.Logger, metrics discovery.DiscovererMetrics) (*LightsailDiscovery, error) {
 	m, ok := metrics.(*lightsailMetrics)
 	if !ok {
-		return nil, fmt.Errorf("invalid discovery metrics type")
+		return nil, errors.New("invalid discovery metrics type")
 	}
 
 	if logger == nil {

discovery/azure/azure.go

@@ -186,7 +186,7 @@ type Discovery struct {
 func NewDiscovery(cfg *SDConfig, logger *slog.Logger, metrics discovery.DiscovererMetrics) (*Discovery, error) {
 	m, ok := metrics.(*azureMetrics)
 	if !ok {
-		return nil, fmt.Errorf("invalid discovery metrics type")
+		return nil, errors.New("invalid discovery metrics type")
 	}
 
 	if logger == nil {

discovery/consul/consul.go

@@ -189,7 +189,7 @@ type Discovery struct {
 func NewDiscovery(conf *SDConfig, logger *slog.Logger, metrics discovery.DiscovererMetrics) (*Discovery, error) {
 	m, ok := metrics.(*consulMetrics)
 	if !ok {
-		return nil, fmt.Errorf("invalid discovery metrics type")
+		return nil, errors.New("invalid discovery metrics type")
 	}
 
 	if logger == nil {

discovery/digitalocean/digitalocean.go

@@ -15,6 +15,7 @@ package digitalocean
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"log/slog"
 	"net"
@@ -114,7 +115,7 @@ type Discovery struct {
 func NewDiscovery(conf *SDConfig, logger *slog.Logger, metrics discovery.DiscovererMetrics) (*Discovery, error) {
 	m, ok := metrics.(*digitaloceanMetrics)
 	if !ok {
-		return nil, fmt.Errorf("invalid discovery metrics type")
+		return nil, errors.New("invalid discovery metrics type")
 	}
 
 	d := &Discovery{

discovery/dns/dns.go

@@ -121,7 +121,7 @@ type Discovery struct {
 func NewDiscovery(conf SDConfig, logger *slog.Logger, metrics discovery.DiscovererMetrics) (*Discovery, error) {
 	m, ok := metrics.(*dnsMetrics)
 	if !ok {
-		return nil, fmt.Errorf("invalid discovery metrics type")
+		return nil, errors.New("invalid discovery metrics type")
 	}
 
 	if logger == nil {

discovery/dns/dns_test.go

@@ -15,7 +15,7 @@ package dns
 
 import (
 	"context"
-	"fmt"
+	"errors"
 	"log/slog"
 	"net"
 	"testing"
@@ -53,7 +53,7 @@ func TestDNS(t *testing.T) {
 				Type:            "A",
 			},
 			lookup: func(name string, qtype uint16, logger *slog.Logger) (*dns.Msg, error) {
-				return nil, fmt.Errorf("some error")
+				return nil, errors.New("some error")
 			},
 			expected: []*targetgroup.Group{},
 		},

discovery/eureka/eureka.go

@@ -16,7 +16,6 @@ package eureka
 import (
 	"context"
 	"errors"
-	"fmt"
 	"log/slog"
 	"net"
 	"net/http"
@@ -129,7 +128,7 @@ type Discovery struct {
 func NewDiscovery(conf *SDConfig, logger *slog.Logger, metrics discovery.DiscovererMetrics) (*Discovery, error) {
 	m, ok := metrics.(*eurekaMetrics)
 	if !ok {
-		return nil, fmt.Errorf("invalid discovery metrics type")
+		return nil, errors.New("invalid discovery metrics type")
 	}
 
 	rt, err := config.NewRoundTripperFromConfig(conf.HTTPClientConfig, "eureka_sd")

discovery/file/file.go

@@ -184,7 +184,7 @@ type Discovery struct {
 func NewDiscovery(conf *SDConfig, logger *slog.Logger, metrics discovery.DiscovererMetrics) (*Discovery, error) {
 	fm, ok := metrics.(*fileMetrics)
 	if !ok {
-		return nil, fmt.Errorf("invalid discovery metrics type")
+		return nil, errors.New("invalid discovery metrics type")
 	}
 
 	if logger == nil {

discovery/gce/gce.go

@@ -132,7 +132,7 @@ type Discovery struct {
 func NewDiscovery(conf SDConfig, logger *slog.Logger, metrics discovery.DiscovererMetrics) (*Discovery, error) {
 	m, ok := metrics.(*gceMetrics)
 	if !ok {
-		return nil, fmt.Errorf("invalid discovery metrics type")
+		return nil, errors.New("invalid discovery metrics type")
 	}
 
 	d := &Discovery{

discovery/hetzner/hetzner.go

@@ -138,7 +138,7 @@ type Discovery struct {
 func NewDiscovery(conf *SDConfig, logger *slog.Logger, metrics discovery.DiscovererMetrics) (*refresh.Discovery, error) {
 	m, ok := metrics.(*hetznerMetrics)
 	if !ok {
-		return nil, fmt.Errorf("invalid discovery metrics type")
+		return nil, errors.New("invalid discovery metrics type")
 	}
 
 	r, err := newRefresher(conf, logger)

discovery/http/http.go

@@ -86,17 +86,17 @@ func (c *SDConfig) UnmarshalYAML(unmarshal func(interface{}) error) error {
 		return err
 	}
 	if c.URL == "" {
-		return fmt.Errorf("URL is missing")
+		return errors.New("URL is missing")
 	}
 	parsedURL, err := url.Parse(c.URL)
 	if err != nil {
 		return err
 	}
 	if parsedURL.Scheme != "http" && parsedURL.Scheme != "https" {
-		return fmt.Errorf("URL scheme must be 'http' or 'https'")
+		return errors.New("URL scheme must be 'http' or 'https'")
 	}
 	if parsedURL.Host == "" {
-		return fmt.Errorf("host is missing in URL")
+		return errors.New("host is missing in URL")
 	}
 	return c.HTTPClientConfig.Validate()
 }
@@ -118,7 +118,7 @@ type Discovery struct {
 func NewDiscovery(conf *SDConfig, logger *slog.Logger, clientOpts []config.HTTPClientOption, metrics discovery.DiscovererMetrics) (*Discovery, error) {
 	m, ok := metrics.(*httpMetrics)
 	if !ok {
-		return nil, fmt.Errorf("invalid discovery metrics type")
+		return nil, errors.New("invalid discovery metrics type")
 	}
 
 	if logger == nil {

discovery/ionos/ionos.go

@@ -15,7 +15,6 @@ package ionos
 
 import (
 	"errors"
-	"fmt"
 	"log/slog"
 	"time"
 
@@ -46,7 +45,7 @@ type Discovery struct{}
 func NewDiscovery(conf *SDConfig, logger *slog.Logger, metrics discovery.DiscovererMetrics) (*refresh.Discovery, error) {
 	m, ok := metrics.(*ionosMetrics)
 	if !ok {
-		return nil, fmt.Errorf("invalid discovery metrics type")
+		return nil, errors.New("invalid discovery metrics type")
 	}
 
 	if conf.ionosEndpoint == "" {

discovery/kubernetes/kubernetes.go

@@ -173,28 +173,28 @@ func (c *SDConfig) UnmarshalYAML(unmarshal func(interface{}) error) error {
 		return err
 	}
 	if c.Role == "" {
-		return fmt.Errorf("role missing (one of: pod, service, endpoints, endpointslice, node, ingress)")
+		return errors.New("role missing (one of: pod, service, endpoints, endpointslice, node, ingress)")
 	}
 	err = c.HTTPClientConfig.Validate()
 	if err != nil {
 		return err
 	}
 	if c.APIServer.URL != nil && c.KubeConfig != "" {
 		// Api-server and kubeconfig_file are mutually exclusive
-		return fmt.Errorf("cannot use 'kubeconfig_file' and 'api_server' simultaneously")
+		return errors.New("cannot use 'kubeconfig_file' and 'api_server' simultaneously")
 	}
 	if c.KubeConfig != "" && !reflect.DeepEqual(c.HTTPClientConfig, config.DefaultHTTPClientConfig) {
 		// Kubeconfig_file and custom http config are mutually exclusive
-		return fmt.Errorf("cannot use a custom HTTP client configuration together with 'kubeconfig_file'")
+		return errors.New("cannot use a custom HTTP client configuration together with 'kubeconfig_file'")
 	}
 	if c.APIServer.URL == nil && !reflect.DeepEqual(c.HTTPClientConfig, config.DefaultHTTPClientConfig) {
-		return fmt.Errorf("to use custom HTTP client configuration please provide the 'api_server' URL explicitly")
+		return errors.New("to use custom HTTP client configuration please provide the 'api_server' URL explicitly")
 	}
 	if c.APIServer.URL != nil && c.NamespaceDiscovery.IncludeOwnNamespace {
-		return fmt.Errorf("cannot use 'api_server' and 'namespaces.own_namespace' simultaneously")
+		return errors.New("cannot use 'api_server' and 'namespaces.own_namespace' simultaneously")
 	}
 	if c.KubeConfig != "" && c.NamespaceDiscovery.IncludeOwnNamespace {
-		return fmt.Errorf("cannot use 'kubeconfig_file' and 'namespaces.own_namespace' simultaneously")
+		return errors.New("cannot use 'kubeconfig_file' and 'namespaces.own_namespace' simultaneously")
 	}
 
 	foundSelectorRoles := make(map[Role]struct{})
@@ -288,7 +288,7 @@ func (d *Discovery) getNamespaces() []string {
 func New(l *slog.Logger, metrics discovery.DiscovererMetrics, conf *SDConfig) (*Discovery, error) {
 	m, ok := metrics.(*kubernetesMetrics)
 	if !ok {
-		return nil, fmt.Errorf("invalid discovery metrics type")
+		return nil, errors.New("invalid discovery metrics type")
 	}
 
 	if l == nil {
@@ -672,7 +672,7 @@ func (d *Discovery) newPodsByNodeInformer(plw *cache.ListWatch) cache.SharedInde
 		indexers[nodeIndex] = func(obj interface{}) ([]string, error) {
 			pod, ok := obj.(*apiv1.Pod)
 			if !ok {
-				return nil, fmt.Errorf("object is not a pod")
+				return nil, errors.New("object is not a pod")
 			}
 			return []string{pod.Spec.NodeName}, nil
 		}
@@ -686,7 +686,7 @@ func (d *Discovery) newEndpointsByNodeInformer(plw *cache.ListWatch) cache.Share
 	indexers[podIndex] = func(obj interface{}) ([]string, error) {
 		e, ok := obj.(*apiv1.Endpoints)
 		if !ok {
-			return nil, fmt.Errorf("object is not endpoints")
+			return nil, errors.New("object is not endpoints")
 		}
 		var pods []string
 		for _, target := range e.Subsets {
@@ -705,7 +705,7 @@ func (d *Discovery) newEndpointsByNodeInformer(plw *cache.ListWatch) cache.Share
 	indexers[nodeIndex] = func(obj interface{}) ([]string, error) {
 		e, ok := obj.(*apiv1.Endpoints)
 		if !ok {
-			return nil, fmt.Errorf("object is not endpoints")
+			return nil, errors.New("object is not endpoints")
 		}
 		var nodes []string
 		for _, target := range e.Subsets {
@@ -751,7 +751,7 @@ func (d *Discovery) newEndpointSlicesByNodeInformer(plw *cache.ListWatch, object
 				}
 			}
 		default:
-			return nil, fmt.Errorf("object is not an endpointslice")
+			return nil, errors.New("object is not an endpointslice")
 		}
 
 		return nodes, nil

discovery/linode/linode.go

@@ -141,7 +141,7 @@ type Discovery struct {
 func NewDiscovery(conf *SDConfig, logger *slog.Logger, metrics discovery.DiscovererMetrics) (*Discovery, error) {
 	m, ok := metrics.(*linodeMetrics)
 	if !ok {
-		return nil, fmt.Errorf("invalid discovery metrics type")
+		return nil, errors.New("invalid discovery metrics type")
 	}
 
 	d := &Discovery{

discovery/manager_test.go

@@ -15,6 +15,7 @@ package discovery
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"sort"
 	"strconv"
@@ -1209,9 +1210,9 @@ func TestGaugeFailedConfigs(t *testing.T) {
 
 	c := map[string]Configs{
 		"prometheus": {
-			errorConfig{fmt.Errorf("tests error 0")},
-			errorConfig{fmt.Errorf("tests error 1")},
-			errorConfig{fmt.Errorf("tests error 2")},
+			errorConfig{errors.New("tests error 0")},
+			errorConfig{errors.New("tests error 1")},
+			errorConfig{errors.New("tests error 2")},
 		},
 	}
 	discoveryManager.ApplyConfig(c)

discovery/marathon/marathon.go

@@ -143,7 +143,7 @@ type Discovery struct {
 func NewDiscovery(conf SDConfig, logger *slog.Logger, metrics discovery.DiscovererMetrics) (*Discovery, error) {
 	m, ok := metrics.(*marathonMetrics)
 	if !ok {
-		return nil, fmt.Errorf("invalid discovery metrics type")
+		return nil, errors.New("invalid discovery metrics type")
 	}
 
 	rt, err := config.NewRoundTripperFromConfig(conf.HTTPClientConfig, "marathon_sd")