staticcheck: fix pipeline errors (#3190)

pipeline link: https://github.com/zalando/skipper/actions/runs/10387833964/job/28762375336\?pr\=3188

Signed-off-by: Mustafa Abdelrahman <[email protected]>

Author: MustafaSaber

config/config.go

@@ -959,7 +959,7 @@ func (c *Config) ToOptions() skipper.Options {
 		options.ProxyFlags |= proxy.PatchPath
 	}
 
-	if c.Certificates != nil && len(c.Certificates) > 0 {
+	if len(c.Certificates) > 0 {
 		options.ClientTLS = &tls.Config{
 			Certificates: c.Certificates,
 			MinVersion:   c.getMinTLSVersion(),

filters/apiusagemonitoring/spec.go

@@ -235,7 +235,7 @@ func (s *apiUsageMonitoringSpec) buildPathInfoListFromConfiguration(apis []*apiC
 			continue
 		}
 
-		if api.PathTemplates == nil || len(api.PathTemplates) == 0 {
+		if len(api.PathTemplates) == 0 {
 			s.warnf("args[%d] ignored: does not specify any path template", apiIndex)
 			continue
 		}

filters/tls/pass_client_test.go

@@ -199,7 +199,7 @@ func TestPassTLSClientCert_PEM(t *testing.T) {
 			req, err := http.NewRequest(http.MethodGet, "http://example.com/foo", nil)
 			require.NoError(t, err)
 
-			if test.certContents != nil && len(test.certContents) > 0 {
+			if len(test.certContents) > 0 {
 				req.TLS = buildTLSWith(test.certContents)
 			}
 

swarm/swarm.go

@@ -4,6 +4,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"math"
 	"net"
 	"time"
 
@@ -156,7 +157,7 @@ func newKubernetesSwarm(o Options) (*Swarm, error) {
 	}
 	o.KubernetesOptions.KubernetesAPIBaseURL = u
 
-	if o.SwarmPort == 0 || o.SwarmPort >= 65535 {
+	if o.SwarmPort == 0 || o.SwarmPort == math.MaxUint16 {
 		log.Errorf("Wrong SwarmPort %d, set to default %d instead", o.SwarmPort, DefaultPort)
 		o.SwarmPort = DefaultPort
 	}