modernize: run gopls modernize to bring up to 1.25 (#2920)

hscontrol/auth_test.go

@@ -2760,7 +2760,7 @@ func TestPreAuthKeyLogoutAndReloginDifferentUser(t *testing.T) {
 	require.Equal(t, 2, user2NodesAfter.Len(), "user2 should still have 2 nodes (old nodes from original registration)")
 
 	// Verify original nodes still exist with original users
-	for i := 0; i < 2; i++ {
+	for i := range 2 {
 		node := nodes[i]
 		// User1's original nodes should still be owned by user1
 		registeredNode, found := app.state.GetNodeByMachineKey(node.machineKey.Public(), types.UserID(user1.ID))
@@ -3195,6 +3195,7 @@ func TestNodeReregistrationWithExpiredPreAuthKey(t *testing.T) {
 	assert.Error(t, err, "expired pre-auth key should be rejected")
 	assert.Contains(t, err.Error(), "authkey expired", "error should mention key expiration")
 }
+
 // TestGitHubIssue2830_ExistingNodeCanReregisterWithUsedPreAuthKey tests that an existing node
 // can re-register using a pre-auth key that's already marked as Used=true, as long as:
 // 1. The node is re-registering with the same MachineKey it originally used
@@ -3204,7 +3205,8 @@ func TestNodeReregistrationWithExpiredPreAuthKey(t *testing.T) {
 //
 // Background: When Docker/Kubernetes containers restart, they keep their persistent state
 // (including the MachineKey), but container entrypoints unconditionally run:
-//   tailscale up --authkey=$TS_AUTHKEY
+//
+//	tailscale up --authkey=$TS_AUTHKEY
 //
 // This caused nodes to be rejected after restart because the pre-auth key was already
 // marked as Used=true from the initial registration. The fix allows re-registration of

hscontrol/db/text_serialiser.go

@@ -31,7 +31,7 @@ func decodingError(name string, err error) error {
 // have a type that implements encoding.TextUnmarshaler.
 type TextSerialiser struct{}
 
-func (TextSerialiser) Scan(ctx context.Context, field *schema.Field, dst reflect.Value, dbValue interface{}) (err error) {
+func (TextSerialiser) Scan(ctx context.Context, field *schema.Field, dst reflect.Value, dbValue any) error {
 	fieldValue := reflect.New(field.FieldType)
 
 	// If the field is a pointer, we need to dereference it to get the actual type
@@ -77,10 +77,10 @@ func (TextSerialiser) Scan(ctx context.Context, field *schema.Field, dst reflect
 		}
 	}
 
-	return err
+	return nil
 }
 
-func (TextSerialiser) Value(ctx context.Context, field *schema.Field, dst reflect.Value, fieldValue interface{}) (interface{}, error) {
+func (TextSerialiser) Value(ctx context.Context, field *schema.Field, dst reflect.Value, fieldValue any) (any, error) {
 	switch v := fieldValue.(type) {
 	case encoding.TextMarshaler:
 		// If the value is nil, we return nil, however, go nil values are not

hscontrol/mapper/batcher_test.go

@@ -1136,13 +1136,9 @@ func XTestBatcherChannelClosingRace(t *testing.T) {
 				// First connection
 				ch1 := make(chan *tailcfg.MapResponse, 1)
 
-				wg.Add(1)
-
-				go func() {
-					defer wg.Done()
-
+				wg.Go(func() {
 					batcher.AddNode(testNode.n.ID, ch1, tailcfg.CapabilityVersion(100))
-				}()
+				})
 
 				// Add real work during connection chaos
 				if i%10 == 0 {
@@ -1152,24 +1148,17 @@ func XTestBatcherChannelClosingRace(t *testing.T) {
 				// Rapid second connection - should replace ch1
 				ch2 := make(chan *tailcfg.MapResponse, 1)
 
-				wg.Add(1)
-
-				go func() {
-					defer wg.Done()
-
+				wg.Go(func() {
 					time.Sleep(1 * time.Microsecond)
 					batcher.AddNode(testNode.n.ID, ch2, tailcfg.CapabilityVersion(100))
-				}()
+				})
 
 				// Remove second connection
-				wg.Add(1)
-
-				go func() {
-					defer wg.Done()
 
+				wg.Go(func() {
 					time.Sleep(2 * time.Microsecond)
 					batcher.RemoveNode(testNode.n.ID, ch2)
-				}()
+				})
 
 				wg.Wait()
 
@@ -1789,10 +1778,7 @@ func XTestBatcherScalability(t *testing.T) {
 							// This ensures some nodes stay connected to continue receiving updates
 							startIdx := cycle % len(testNodes)
 
-							endIdx := startIdx + len(testNodes)/4
-							if endIdx > len(testNodes) {
-								endIdx = len(testNodes)
-							}
+							endIdx := min(startIdx+len(testNodes)/4, len(testNodes))
 
 							if startIdx >= endIdx {
 								startIdx = 0
@@ -2313,7 +2299,7 @@ func TestBatcherRapidReconnection(t *testing.T) {
 			receivedCount := 0
 			timeout := time.After(500 * time.Millisecond)
 
-			for i := 0; i < len(allNodes); i++ {
+			for i := range allNodes {
 				select {
 				case update := <-newChannels[i]:
 					if update != nil {

hscontrol/policy/v2/filter.go

@@ -3,6 +3,7 @@ package v2
 import (
 	"errors"
 	"fmt"
+	"slices"
 	"time"
 
 	"github.com/juanfont/headscale/hscontrol/types"
@@ -178,11 +179,8 @@ func (pol *Policy) compileACLWithAutogroupSelf(
 			for _, ips := range resolvedSrcIPs {
 				for _, n := range sameUserNodes {
 					// Check if any of this node's IPs are in the source set
-					for _, nodeIP := range n.IPs() {
-						if ips.Contains(nodeIP) {
-							n.AppendToIPSet(&srcIPs)
-							break
-						}
+					if slices.ContainsFunc(n.IPs(), ips.Contains) {
+						n.AppendToIPSet(&srcIPs)
 					}
 				}
 			}
@@ -375,11 +373,8 @@ func (pol *Policy) compileSSHPolicy(
 				var filteredSrcIPs netipx.IPSetBuilder
 				for _, n := range sameUserNodes {
 					// Check if any of this node's IPs are in the source set
-					for _, nodeIP := range n.IPs() {
-						if srcIPs.Contains(nodeIP) {
-							n.AppendToIPSet(&filteredSrcIPs)
-							break // Found this node, move to next
-						}
+					if slices.ContainsFunc(n.IPs(), srcIPs.Contains) {
+						n.AppendToIPSet(&filteredSrcIPs) // Found this node, move to next
 					}
 				}
 

hscontrol/policy/v2/filter_test.go

@@ -3,6 +3,7 @@ package v2
 import (
 	"encoding/json"
 	"net/netip"
+	"slices"
 	"strings"
 	"testing"
 	"time"
@@ -906,14 +907,7 @@ func TestCompileFilterRulesForNodeWithAutogroupSelf(t *testing.T) {
 	}
 
 	for _, expectedIP := range expectedDestIPs {
-		found := false
-
-		for _, actualIP := range actualDestIPs {
-			if actualIP == expectedIP {
-				found = true
-				break
-			}
-		}
+		found := slices.Contains(actualDestIPs, expectedIP)
 
 		if !found {
 			t.Errorf("expected destination IP %s to be included, got: %v", expectedIP, actualDestIPs)

hscontrol/policy/v2/types.go

@@ -1007,7 +1007,7 @@ func (g Groups) Contains(group *Group) error {
 // with "group:". If any group name is invalid, an error is returned.
 func (g *Groups) UnmarshalJSON(b []byte) error {
 	// First unmarshal as a generic map to validate group names first
-	var rawMap map[string]interface{}
+	var rawMap map[string]any
 	if err := json.Unmarshal(b, &rawMap); err != nil {
 		return err
 	}
@@ -1024,7 +1024,7 @@ func (g *Groups) UnmarshalJSON(b []byte) error {
 	rawGroups := make(map[string][]string)
 	for key, value := range rawMap {
 		switch v := value.(type) {
-		case []interface{}:
+		case []any:
 			// Convert []interface{} to []string
 			var stringSlice []string
 			for _, item := range v {

hscontrol/policy/v2/utils.go

@@ -39,9 +39,10 @@ func parsePortRange(portDef string) ([]tailcfg.PortRange, error) {
 	}
 
 	var portRanges []tailcfg.PortRange
-	parts := strings.Split(portDef, ",")
 
-	for _, part := range parts {
+	parts := strings.SplitSeq(portDef, ",")
+
+	for part := range parts {
 		if strings.Contains(part, "-") {
 			rangeParts := strings.Split(part, "-")
 			rangeParts = slices.DeleteFunc(rangeParts, func(e string) bool {

hscontrol/state/debug.go

@@ -200,9 +200,9 @@ func (s *State) DebugSSHPolicies() map[string]*tailcfg.SSHPolicy {
 }
 
 // DebugRegistrationCache returns debug information about the registration cache.
-func (s *State) DebugRegistrationCache() map[string]interface{} {
+func (s *State) DebugRegistrationCache() map[string]any {
 	// The cache doesn't expose internal statistics, so we provide basic info
-	result := map[string]interface{}{
+	result := map[string]any{
 		"type":       "zcache",
 		"expiration": registerCacheExpiration.String(),
 		"cleanup":    registerCacheCleanup.String(),

hscontrol/state/node_store_test.go

@@ -872,7 +872,7 @@ func TestNodeStoreConcurrentPutNode(t *testing.T) {
 
 	var wg sync.WaitGroup
 	results := make(chan bool, concurrentOps)
-	for i := 0; i < concurrentOps; i++ {
+	for i := range concurrentOps {
 		wg.Add(1)
 		go func(nodeID int) {
 			defer wg.Done()
@@ -904,7 +904,7 @@ func TestNodeStoreBatchingEfficiency(t *testing.T) {
 
 	var wg sync.WaitGroup
 	results := make(chan bool, ops)
-	for i := 0; i < ops; i++ {
+	for i := range ops {
 		wg.Add(1)
 		go func(nodeID int) {
 			defer wg.Done()
@@ -941,11 +941,12 @@ func TestNodeStoreRaceConditions(t *testing.T) {
 	var wg sync.WaitGroup
 	errors := make(chan error, numGoroutines*opsPerGoroutine)
 
-	for i := 0; i < numGoroutines; i++ {
+	for i := range numGoroutines {
 		wg.Add(1)
 		go func(gid int) {
 			defer wg.Done()
-			for j := 0; j < opsPerGoroutine; j++ {
+
+			for j := range opsPerGoroutine {
 				switch j % 3 {
 				case 0:
 					resultNode, _ := store.UpdateNode(nodeID, func(n *types.Node) {
@@ -993,7 +994,7 @@ func TestNodeStoreResourceCleanup(t *testing.T) {
 	afterStartGoroutines := runtime.NumGoroutine()
 
 	const ops = 100
-	for i := 0; i < ops; i++ {
+	for i := range ops {
 		nodeID := types.NodeID(i + 1)
 		node := createConcurrentTestNode(nodeID, "cleanup-node")
 		resultNode := store.PutNode(node)
@@ -1100,7 +1101,7 @@ func TestNodeStoreOperationTimeout(t *testing.T) {
 
 // --- Edge case: update non-existent node ---
 func TestNodeStoreUpdateNonExistentNode(t *testing.T) {
-	for i := 0; i < 10; i++ {
+	for i := range 10 {
 		store := NewNodeStore(nil, allowAllPeersFunc, TestBatchSize, TestBatchTimeout)
 		store.Start()
 		nonExistentID := types.NodeID(999 + i)
@@ -1124,8 +1125,7 @@ func BenchmarkNodeStoreAllocations(b *testing.B) {
 	store.Start()
 	defer store.Stop()
 
-	b.ResetTimer()
-	for i := 0; i < b.N; i++ {
+	for i := 0; b.Loop(); i++ {
 		nodeID := types.NodeID(i + 1)
 		node := createConcurrentTestNode(nodeID, "bench-node")
 		store.PutNode(node)

hscontrol/types/common.go

@@ -220,10 +220,12 @@ func DefaultBatcherWorkers() int {
 // DefaultBatcherWorkersFor returns the default number of batcher workers for a given CPU count.
 // Default to 3/4 of CPU cores, minimum 1, no maximum.
 func DefaultBatcherWorkersFor(cpuCount int) int {
-	defaultWorkers := (cpuCount * 3) / 4
-	if defaultWorkers < 1 {
-		defaultWorkers = 1
-	}
+	const (
+		workerNumerator   = 3
+		workerDenominator = 4
+	)
+
+	defaultWorkers := max((cpuCount*workerNumerator)/workerDenominator, 1)
 
 	return defaultWorkers
 }

hscontrol/util/log.go

@@ -49,22 +49,22 @@ func (l *DBLogWrapper) LogMode(gormLogger.LogLevel) gormLogger.Interface {
 	return l
 }
 
-func (l *DBLogWrapper) Info(ctx context.Context, msg string, data ...interface{}) {
+func (l *DBLogWrapper) Info(ctx context.Context, msg string, data ...any) {
 	l.Logger.Info().Msgf(msg, data...)
 }
 
-func (l *DBLogWrapper) Warn(ctx context.Context, msg string, data ...interface{}) {
+func (l *DBLogWrapper) Warn(ctx context.Context, msg string, data ...any) {
 	l.Logger.Warn().Msgf(msg, data...)
 }
 
-func (l *DBLogWrapper) Error(ctx context.Context, msg string, data ...interface{}) {
+func (l *DBLogWrapper) Error(ctx context.Context, msg string, data ...any) {
 	l.Logger.Error().Msgf(msg, data...)
 }
 
 func (l *DBLogWrapper) Trace(ctx context.Context, begin time.Time, fc func() (sql string, rowsAffected int64), err error) {
 	elapsed := time.Since(begin)
 	sql, rowsAffected := fc()
-	fields := map[string]interface{}{
+	fields := map[string]any{
 		"duration":     elapsed,
 		"sql":          sql,
 		"rowsAffected": rowsAffected,
@@ -83,7 +83,7 @@ func (l *DBLogWrapper) Trace(ctx context.Context, begin time.Time, fc func() (sq
 	l.Logger.Debug().Fields(fields).Msgf("")
 }
 
-func (l *DBLogWrapper) ParamsFilter(ctx context.Context, sql string, params ...interface{}) (string, []interface{}) {
+func (l *DBLogWrapper) ParamsFilter(ctx context.Context, sql string, params ...any) (string, []any) {
 	if l.ParameterizedQueries {
 		return sql, nil
 	}