all: use slices.Collect with maps.Keys instead of xmaps.Keysdsnet/slices-collect

In Go 1.23, the standard maps.Keys helper was altered relative to xmaps.Keys
to return and iterator, which can be used with slices.Collect.

Also, Go 1.21 added the clear built-in, which replaces xmaps.Clear,
and is semantically more correct with respect to NaNs.

Updates #8632
Updates #12912
Updates #cleanup

Signed-off-by: Joe Tsai <joetsai@digital-static.net>

14 files changed, 37 insertions, 38 deletions

diff --git a/appc/appconnector.go b/appc/appconnector.go
index 671ced953..71e46c59c 100644
--- a/appc/appconnector.go
+++ b/appc/appconnector.go
@@ -12,13 +12,13 @@ package appc
 import (
 	"context"
 	"fmt"
+	"maps"
 	"net/netip"
 	"slices"
 	"strings"
 	"sync"
 	"time"
 
-	xmaps "golang.org/x/exp/maps"
 	"golang.org/x/net/dns/dnsmessage"
 	"tailscale.com/types/logger"
 	"tailscale.com/types/views"
@@ -291,11 +291,11 @@ func (e *AppConnector) updateDomains(domains []string) {
 			}
 		}
 		if err := e.routeAdvertiser.UnadvertiseRoute(toRemove...); err != nil {
-			e.logf("failed to unadvertise routes on domain removal: %v: %v: %v", xmaps.Keys(oldDomains), toRemove, err)
+			e.logf("failed to unadvertise routes on domain removal: %v: %v: %v", slices.Collect(maps.Keys(oldDomains)), toRemove, err)
 		}
 	}
 
-	e.logf("handling domains: %v and wildcards: %v", xmaps.Keys(e.domains), e.wildcards)
+	e.logf("handling domains: %v and wildcards: %v", slices.Collect(maps.Keys(e.domains)), e.wildcards)
 }
 
 // updateRoutes merges the supplied routes into the currently configured routes. The routes supplied
@@ -354,7 +354,7 @@ func (e *AppConnector) Domains() views.Slice[string] {
 	e.mu.Lock()
 	defer e.mu.Unlock()
 
-	return views.SliceOf(xmaps.Keys(e.domains))
+	return views.SliceOf(slices.Collect(maps.Keys(e.domains)))
 }
 
 // DomainRoutes returns a map of domains to resolved IP
diff --git a/appc/appconnector_test.go b/appc/appconnector_test.go
index 7dba8cebd..4cd4b2e9e 100644
--- a/appc/appconnector_test.go
+++ b/appc/appconnector_test.go
@@ -5,13 +5,13 @@ package appc
 
 import (
 	"context"
+	"maps"
 	"net/netip"
 	"reflect"
 	"slices"
 	"testing"
 	"time"
 
-	xmaps "golang.org/x/exp/maps"
 	"golang.org/x/net/dns/dnsmessage"
 	"tailscale.com/appc/appctest"
 	"tailscale.com/tstest"
@@ -50,7 +50,7 @@ func TestUpdateDomains(t *testing.T) {
 		// domains are explicitly downcased on set.
 		a.UpdateDomains([]string{"UP.EXAMPLE.COM"})
 		a.Wait(ctx)
-		if got, want := xmaps.Keys(a.domains), []string{"up.example.com"}; !slices.Equal(got, want) {
+		if got, want := slices.Collect(maps.Keys(a.domains)), []string{"up.example.com"}; !slices.Equal(got, want) {
 			t.Errorf("got %v; want %v", got, want)
 		}
 	}
diff --git a/cmd/tailscale/cli/exitnode.go b/cmd/tailscale/cli/exitnode.go
index 6b9247a7b..d41e42092 100644
--- a/cmd/tailscale/cli/exitnode.go
+++ b/cmd/tailscale/cli/exitnode.go
@@ -9,13 +9,13 @@ import (
 	"errors"
 	"flag"
 	"fmt"
+	"maps"
 	"slices"
 	"strings"
 	"text/tabwriter"
 
 	"github.com/kballard/go-shellquote"
 	"github.com/peterbourgon/ff/v3/ffcli"
-	xmaps "golang.org/x/exp/maps"
 	"tailscale.com/envknob"
 	"tailscale.com/ipn/ipnstate"
 	"tailscale.com/tailcfg"
@@ -255,7 +255,7 @@ func filterFormatAndSortExitNodes(peers []*ipnstate.PeerStatus, filterBy string)
 	}
 
 	filteredExitNodes := filteredExitNodes{
-		Countries: xmaps.Values(countries),
+		Countries: slices.Collect(maps.Values(countries)),
 	}
 
 	for _, country := range filteredExitNodes.Countries {
diff --git a/cmd/testwrapper/testwrapper.go b/cmd/testwrapper/testwrapper.go
index 9b8d7a7c1..75db00736 100644
--- a/cmd/testwrapper/testwrapper.go
+++ b/cmd/testwrapper/testwrapper.go
@@ -16,6 +16,7 @@ import (
 	"fmt"
 	"io"
 	"log"
+	"maps"
 	"os"
 	"os/exec"
 	"slices"
@@ -29,7 +30,6 @@ import (
 	"github.com/dave/courtney/tester"
 	"github.com/dave/patsy"
 	"github.com/dave/patsy/vos"
-	xmaps "golang.org/x/exp/maps"
 	"tailscale.com/cmd/testwrapper/flakytest"
 )
 
@@ -343,7 +343,7 @@ func main() {
 		if len(toRetry) == 0 {
 			continue
 		}
-		pkgs := xmaps.Keys(toRetry)
+		pkgs := slices.Collect(maps.Keys(toRetry))
 		sort.Strings(pkgs)
 		nextRun := &nextRun{
 			attempt: thisRun.attempt + 1,
diff --git a/ipn/ipnlocal/local.go b/ipn/ipnlocal/local.go
index 06dd84831..1bf7be4b5 100644
--- a/ipn/ipnlocal/local.go
+++ b/ipn/ipnlocal/local.go
@@ -37,7 +37,6 @@ import (
 
 	"go4.org/mem"
 	"go4.org/netipx"
-	xmaps "golang.org/x/exp/maps"
 	"golang.org/x/net/dns/dnsmessage"
 	"gvisor.dev/gvisor/pkg/tcpip"
 	"tailscale.com/appc"
@@ -1925,7 +1924,7 @@ func (b *LocalBackend) DisablePortMapperForTest() {
 func (b *LocalBackend) PeersForTest() []tailcfg.NodeView {
 	b.mu.Lock()
 	defer b.mu.Unlock()
-	ret := xmaps.Values(b.peers)
+	ret := slices.Collect(maps.Values(b.peers))
 	slices.SortFunc(ret, func(a, b tailcfg.NodeView) int {
 		return cmp.Compare(a.ID(), b.ID())
 	})
@@ -7150,9 +7149,9 @@ func suggestExitNode(report *netcheck.Report, netMap *netmap.NetworkMap, prevSug
 	// First, try to select an exit node that has the closest DERP home, based on lastReport's DERP latency.
 	// If there are no latency values, it returns an arbitrary region
 	if len(candidatesByRegion) > 0 {
-		minRegion := minLatencyDERPRegion(xmaps.Keys(candidatesByRegion), report)
+		minRegion := minLatencyDERPRegion(slices.Collect(maps.Keys(candidatesByRegion)), report)
 		if minRegion == 0 {
-			minRegion = selectRegion(views.SliceOf(xmaps.Keys(candidatesByRegion)))
+			minRegion = selectRegion(views.SliceOf(slices.Collect(maps.Keys(candidatesByRegion))))
 		}
 		regionCandidates, ok := candidatesByRegion[minRegion]
 		if !ok {
diff --git a/net/dns/manager.go b/net/dns/manager.go
index 51a0fa12c..988c76633 100644
--- a/net/dns/manager.go
+++ b/net/dns/manager.go
@@ -9,6 +9,7 @@ import (
 	"encoding/binary"
 	"errors"
 	"io"
+	"maps"
 	"net"
 	"net/netip"
 	"runtime"
@@ -18,7 +19,6 @@ import (
 	"sync/atomic"
 	"time"
 
-	xmaps "golang.org/x/exp/maps"
 	"tailscale.com/control/controlknobs"
 	"tailscale.com/health"
 	"tailscale.com/net/dns/resolver"
@@ -203,7 +203,7 @@ func compileHostEntries(cfg Config) (hosts []*HostEntry) {
 	if len(hostsMap) == 0 {
 		return nil
 	}
-	hosts = xmaps.Values(hostsMap)
+	hosts = slices.Collect(maps.Values(hostsMap))
 	slices.SortFunc(hosts, func(a, b *HostEntry) int {
 		if len(a.Hosts) == 0 && len(b.Hosts) == 0 {
 			return 0
diff --git a/util/lru/lru_test.go b/util/lru/lru_test.go
index fb538efbe..ffbd98597 100644
--- a/util/lru/lru_test.go
+++ b/util/lru/lru_test.go
@@ -5,12 +5,13 @@ package lru
 
 import (
 	"bytes"
+	"maps"
 	"math/rand"
+	"slices"
 	"strings"
 	"testing"
 
 	"github.com/google/go-cmp/cmp"
-	xmaps "golang.org/x/exp/maps"
 )
 
 func TestLRU(t *testing.T) {
@@ -75,7 +76,7 @@ func TestStressEvictions(t *testing.T) {
 	for len(vm) < numKeys {
 		vm[rand.Uint64()] = true
 	}
-	vals := xmaps.Keys(vm)
+	vals := slices.Collect(maps.Keys(vm))
 
 	c := Cache[uint64, bool]{
 		MaxEntries: cacheSize,
@@ -106,7 +107,7 @@ func TestStressBatchedEvictions(t *testing.T) {
 	for len(vm) < numKeys {
 		vm[rand.Uint64()] = true
 	}
-	vals := xmaps.Keys(vm)
+	vals := slices.Collect(maps.Keys(vm))
 
 	c := Cache[uint64, bool]{}
 
diff --git a/util/nocasemaps/nocase_test.go b/util/nocasemaps/nocase_test.go
index 5275b3ee6..d295cd3ba 100644
--- a/util/nocasemaps/nocase_test.go
+++ b/util/nocasemaps/nocase_test.go
@@ -8,7 +8,6 @@ import (
 	"testing"
 
 	qt "github.com/frankban/quicktest"
-	xmaps "golang.org/x/exp/maps"
 )
 
 func pair[A, B any](a A, b B) (out struct {
@@ -130,7 +129,7 @@ func Benchmark(b *testing.B) {
 					for range b.N {
 						testMap[strings.ToLower(key)] = testValue
 					}
-					xmaps.Clear(testMap)
+					clear(testMap)
 				})
 				b.Run("NoCase", func(b *testing.B) {
 					b.ReportAllocs()
@@ -138,7 +137,7 @@ func Benchmark(b *testing.B) {
 					for range b.N {
 						Set(testMap, key, testValue)
 					}
-					xmaps.Clear(testMap)
+					clear(testMap)
 				})
 			})
 			b.Run("Delete", func(b *testing.B) {
diff --git a/util/syspolicy/internal/metrics/metrics.go b/util/syspolicy/internal/metrics/metrics.go
index 2ea02278a..757e30bee 100644
--- a/util/syspolicy/internal/metrics/metrics.go
+++ b/util/syspolicy/internal/metrics/metrics.go
@@ -5,11 +5,10 @@
 package metrics
 
 import (
+	"maps"
 	"strings"
 	"sync"
 
-	xmaps "golang.org/x/exp/maps"
-
 	"tailscale.com/syncs"
 	"tailscale.com/types/lazy"
 	"tailscale.com/util/clientmetric"
@@ -268,7 +267,7 @@ func SetHooksForTest(tb internal.TB, addMetric, setMetric metricFn) {
 	})
 
 	settingMetricsMu.Lock()
-	oldSettingMetricsMap := xmaps.Clone(settingMetricsMap)
+	oldSettingMetricsMap := maps.Clone(settingMetricsMap)
 	clear(settingMetricsMap)
 	settingMetricsMu.Unlock()
 	tb.Cleanup(func() {
diff --git a/util/syspolicy/setting/snapshot.go b/util/syspolicy/setting/snapshot.go
index 512bc487c..484890eae 100644
--- a/util/syspolicy/setting/snapshot.go
+++ b/util/syspolicy/setting/snapshot.go
@@ -9,7 +9,6 @@ import (
 	"slices"
 	"strings"
 
-	xmaps "golang.org/x/exp/maps"
 	"tailscale.com/util/deephash"
 )
 
@@ -24,7 +23,7 @@ type Snapshot struct {
 
 // NewSnapshot returns a new [Snapshot] with the specified items and options.
 func NewSnapshot(items map[Key]RawItem, opts ...SummaryOption) *Snapshot {
-	return &Snapshot{m: xmaps.Clone(items), sig: deephash.Hash(&items), summary: SummaryWith(opts...)}
+	return &Snapshot{m: maps.Clone(items), sig: deephash.Hash(&items), summary: SummaryWith(opts...)}
 }
 
 // All returns an iterator over policy settings in s. The iteration order is not
@@ -164,7 +163,7 @@ func MergeSnapshots(snapshot1, snapshot2 *Snapshot) *Snapshot {
 		return &Snapshot{snapshot2.m, snapshot2.sig, SummaryWith(summaryOpts...)}
 	}
 	m := make(map[Key]RawItem, snapshot1.Len()+snapshot2.Len())
-	xmaps.Copy(m, snapshot1.m)
-	xmaps.Copy(m, snapshot2.m) // snapshot2 has higher precedence
+	maps.Copy(m, snapshot1.m)
+	maps.Copy(m, snapshot2.m) // snapshot2 has higher precedence
 	return &Snapshot{m, deephash.Hash(&m), SummaryWith(summaryOpts...)}
 }
diff --git a/util/syspolicy/source/test_store.go b/util/syspolicy/source/test_store.go
index bb8e164fb..fce87d380 100644
--- a/util/syspolicy/source/test_store.go
+++ b/util/syspolicy/source/test_store.go
@@ -5,10 +5,11 @@ package source
 
 import (
 	"fmt"
+	"maps"
+	"slices"
 	"sync"
 	"sync/atomic"
 
-	xmaps "golang.org/x/exp/maps"
 	"tailscale.com/util/mak"
 	"tailscale.com/util/set"
 	"tailscale.com/util/syspolicy/internal"
@@ -294,7 +295,7 @@ func (s *TestStore) Suspend() {
 	s.mu.Lock()
 	defer s.mu.Unlock()
 	if s.suspendCount++; s.suspendCount == 1 {
-		s.mw = xmaps.Clone(s.mr)
+		s.mw = maps.Clone(s.mr)
 	}
 }
 
@@ -421,7 +422,7 @@ func (s *TestStore) notifyPolicyChanged() {
 		s.mu.RUnlock()
 		return
 	}
-	cbs := xmaps.Values(s.cbs)
+	cbs := slices.Collect(maps.Values(s.cbs))
 	s.mu.RUnlock()
 
 	var wg sync.WaitGroup
diff --git a/wgengine/filter/filter_test.go b/wgengine/filter/filter_test.go
index f2796d71f..5f1a32bfa 100644
--- a/wgengine/filter/filter_test.go
+++ b/wgengine/filter/filter_test.go
@@ -8,6 +8,7 @@ import (
 	"encoding/json"
 	"flag"
 	"fmt"
+	"maps"
 	"net/netip"
 	"os"
 	"slices"
@@ -18,7 +19,6 @@ import (
 	"github.com/google/go-cmp/cmp"
 	"github.com/google/go-cmp/cmp/cmpopts"
 	"go4.org/netipx"
-	xmaps "golang.org/x/exp/maps"
 	"tailscale.com/net/flowtrack"
 	"tailscale.com/net/ipset"
 	"tailscale.com/net/packet"
@@ -997,7 +997,7 @@ func TestPeerCaps(t *testing.T) {
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			got := xmaps.Keys(filt.CapsWithValues(netip.MustParseAddr(tt.src), netip.MustParseAddr(tt.dst)))
+			got := slices.Collect(maps.Keys(filt.CapsWithValues(netip.MustParseAddr(tt.src), netip.MustParseAddr(tt.dst))))
 			slices.Sort(got)
 			slices.Sort(tt.want)
 			if !slices.Equal(got, tt.want) {
diff --git a/wgengine/magicsock/endpoint.go b/wgengine/magicsock/endpoint.go
index 53ecb84de..b6d56b8d7 100644
--- a/wgengine/magicsock/endpoint.go
+++ b/wgengine/magicsock/endpoint.go
@@ -9,6 +9,7 @@ import (
 	"encoding/binary"
 	"errors"
 	"fmt"
+	"maps"
 	"math"
 	"math/rand/v2"
 	"net"
@@ -20,7 +21,6 @@ import (
 	"sync/atomic"
 	"time"
 
-	xmaps "golang.org/x/exp/maps"
 	"golang.org/x/net/ipv4"
 	"golang.org/x/net/ipv6"
 	"tailscale.com/disco"
@@ -586,7 +586,7 @@ func (de *endpoint) addrForWireGuardSendLocked(now mono.Time) (udpAddr netip.Add
 	needPing := len(de.endpointState) > 1 && now.Sub(oldestPing) > wireguardPingInterval
 
 	if !udpAddr.IsValid() {
-		candidates := xmaps.Keys(de.endpointState)
+		candidates := slices.Collect(maps.Keys(de.endpointState))
 
 		// Randomly select an address to use until we retrieve latency information
 		// and give it a short trustBestAddrUntil time so we avoid flapping between
diff --git a/wgengine/magicsock/magicsock_test.go b/wgengine/magicsock/magicsock_test.go
index 6b2d961b9..d37a3468d 100644
--- a/wgengine/magicsock/magicsock_test.go
+++ b/wgengine/magicsock/magicsock_test.go
@@ -12,6 +12,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"maps"
 	"math/rand"
 	"net"
 	"net/http"
@@ -19,6 +20,7 @@ import (
 	"net/netip"
 	"os"
 	"runtime"
+	"slices"
 	"strconv"
 	"strings"
 	"sync"
@@ -32,7 +34,6 @@ import (
 	"github.com/tailscale/wireguard-go/device"
 	"github.com/tailscale/wireguard-go/tun/tuntest"
 	"go4.org/mem"
-	xmaps "golang.org/x/exp/maps"
 	"golang.org/x/net/icmp"
 	"golang.org/x/net/ipv4"
 	"tailscale.com/cmd/testwrapper/flakytest"
@@ -1129,7 +1130,7 @@ func testTwoDevicePing(t *testing.T, d *devices) {
 			}
 		}
 		t.Helper()
-		t.Errorf("missing any connection to %s from %s", wantConns, xmaps.Keys(stats))
+		t.Errorf("missing any connection to %s from %s", wantConns, slices.Collect(maps.Keys(stats)))
 	}
 
 	addrPort := netip.MustParseAddrPort