refactor: enable linter copyloopvar (scionproto#4708)

The loop variable problem is no more since Go 1.22 (see
https://go.dev/blog/loopvar-preview).

- Remove unnecessary variable copying.
- Remove the loopvar semgrep linter.

.golangcilint.yml

@@ -11,7 +11,7 @@ linters:
     - typecheck
     - unused
     # Extended linters.
-    # - copyloopvar
+    - copyloopvar
     - rowserrcheck
     - sqlclosecheck
     - unconvert

control/beaconing/extender_test.go

@@ -90,7 +90,6 @@ func TestDefaultExtenderExtend(t *testing.T) {
 		},
 	}
 	for name, tc := range testsCases {
-		name, tc := name, tc
 		t.Run(name, func(t *testing.T) {
 			mctrl := gomock.NewController(t)
 			defer mctrl.Finish()
@@ -332,7 +331,6 @@ func TestDefaultExtenderExtend(t *testing.T) {
 			},
 		}
 		for name, tc := range testCases {
-			name, tc := name, tc
 			t.Run(name, func(t *testing.T) {
 				mctrl := gomock.NewController(t)
 				defer mctrl.Finish()

control/beaconing/handler_test.go

@@ -160,7 +160,6 @@ func TestHandlerHandleBeacon(t *testing.T) {
 				}
 				b.Segment.ASEntries[b.Segment.MaxIdx()].Local = addr.MustParseIA("1-ff00:0:111")
 				return b
-
 			},
 			Peer: func() *snet.UDPAddr {
 				return &snet.UDPAddr{
@@ -255,7 +254,6 @@ func TestHandlerHandleBeacon(t *testing.T) {
 		},
 	}
 	for name, tc := range testCases {
-		name, tc := name, tc
 		t.Run(name, func(t *testing.T) {
 			t.Parallel()
 			mctrl := gomock.NewController(t)

control/beaconing/propagator.go

@@ -111,8 +111,6 @@ func (p *Propagator) run(ctx context.Context) error {
 			continue
 		}
 		wg.Add(1)
-		intf := intf
-		beacons := beacons
 		go func() {
 			defer log.HandlePanic()
 			defer wg.Done()
@@ -162,7 +160,6 @@ func (p *Propagator) beaconsPerInterface(
 	ctx context.Context,
 	intfs []*ifstate.Interface,
 ) (map[*ifstate.Interface][]beacon.Beacon, error) {
-
 	allBeacons, err := p.Provider.BeaconsToPropagate(ctx)
 	if err != nil {
 		return nil, serrors.Wrap("fetching beacons to propagate", err)
@@ -207,7 +204,6 @@ func (p *Propagator) logCandidateBeacons(
 	logger log.Logger,
 	beaconsPerInterface map[*ifstate.Interface][]beacon.Beacon,
 ) {
-
 	if !logger.Enabled(log.DebugLevel) {
 		return
 	}
@@ -282,7 +278,6 @@ func (p *propagator) Propagate(ctx context.Context) error {
 	var wg sync.WaitGroup
 	for _, b := range p.beacons {
 		wg.Add(1)
-		b := b
 		go func() {
 			defer log.HandlePanic()
 			defer wg.Done()

control/drkey/arc_test.go

@@ -81,7 +81,6 @@ func TestLevel1ARC(t *testing.T) {
 		},
 	}
 	for name, tc := range testCases {
-		name, tc := name, tc
 		t.Run(name, func(t *testing.T) {
 			t.Parallel()
 

control/drkey/grpc/drkey_service_test.go

@@ -43,8 +43,10 @@ var (
 	tcpHost2 = netip.MustParseAddrPort("127.0.0.2:12345")
 )
 
-var _ cppb.DRKeyInterServiceServer = &dk_grpc.Server{}
-var _ cppb.DRKeyIntraServiceServer = &dk_grpc.Server{}
+var (
+	_ cppb.DRKeyInterServiceServer = &dk_grpc.Server{}
+	_ cppb.DRKeyIntraServiceServer = &dk_grpc.Server{}
+)
 
 func TestDRKeySV(t *testing.T) {
 	sv, targetResp := getSVandResp(t)
@@ -100,7 +102,6 @@ func TestDRKeySV(t *testing.T) {
 	for name, tc := range testCases {
 		t.Run(name, func(t *testing.T) {
 			t.Parallel()
-
 		})
 		server := dk_grpc.Server{
 			LocalIA:            ia111,
@@ -160,9 +161,7 @@ func TestValidateASHost(t *testing.T) {
 		},
 	}
 	for name, tc := range testCases {
-		name, tc := name, tc
 		t.Run(name, func(t *testing.T) {
-
 			err := dk_grpc.ValidateASHostReq(tc.req, tc.LocalIA, tc.peerAddr)
 			tc.assertErr(t, err)
 		})
@@ -216,9 +215,7 @@ func TestValidateHostASReq(t *testing.T) {
 		},
 	}
 	for name, tc := range testCases {
-		name, tc := name, tc
 		t.Run(name, func(t *testing.T) {
-
 			err := dk_grpc.ValidateHostASReq(tc.req, tc.LocalIA, tc.peerAddr)
 			tc.assertErr(t, err)
 		})
@@ -286,9 +283,7 @@ func TestValidateHostHostReq(t *testing.T) {
 		},
 	}
 	for name, tc := range testCases {
-		name, tc := name, tc
 		t.Run(name, func(t *testing.T) {
-
 			err := dk_grpc.ValidateHostHostReq(tc.req, tc.LocalIA, tc.peerAddr)
 			tc.assertErr(t, err)
 		})

control/drkey/prefetcher.go

@@ -55,7 +55,6 @@ func (f *Prefetcher) Run(ctx context.Context) {
 	logger.Debug("Prefetching level 1 DRKeys", "AS, proto:", keysMeta)
 	when := time.Now().Add(f.KeyDuration)
 	for _, key := range keysMeta {
-		key := key
 		wg.Add(1)
 		go func() {
 			defer log.HandlePanic()
@@ -73,7 +72,6 @@ func getLevel1Key(
 	proto drkey.Protocol,
 	valTime time.Time,
 ) {
-
 	meta := drkey.Level1Meta{
 		Validity: valTime,
 		SrcIA:    srcIA,

control/mgmtapi/api_test.go

@@ -629,7 +629,8 @@ func TestAPI(t *testing.T) {
 							Base:   2,
 							Serial: 1,
 							ISD:    12,
-						}},
+						},
+					},
 				)
 				h.EXPECT().GetCAHealth(gomock.Any()).Return(
 					api.Available, true,
@@ -881,7 +882,6 @@ func TestAPI(t *testing.T) {
 	}
 
 	for name, tc := range testCases {
-		name, tc := name, tc
 		t.Run(name, func(t *testing.T) {
 			t.Parallel()
 			ctrl := gomock.NewController(t)
@@ -902,7 +902,7 @@ func TestAPI(t *testing.T) {
 			goldenFile := "testdata/" + xtest.SanitizedName(t)
 			if *update {
 				raw := strings.ReplaceAll(rr.Body.String(), expiresAt, "EXPIRES_AT")
-				require.NoError(t, os.WriteFile(goldenFile, []byte(raw), 0666))
+				require.NoError(t, os.WriteFile(goldenFile, []byte(raw), 0o666))
 			}
 			goldenRaw, err := os.ReadFile(goldenFile)
 			require.NoError(t, err)

control/trust/crypto_loader_test.go

@@ -72,7 +72,6 @@ func TestChainLoaderChains(t *testing.T) {
 		},
 	}
 	for name, tc := range testCases {
-		name, tc := name, tc
 		t.Run(name, func(t *testing.T) {
 			t.Parallel()
 			ctrl := gomock.NewController(t)

control/trust/grpc/proto_test.go

@@ -95,7 +95,6 @@ func TestReqToTRCQuery(t *testing.T) {
 		},
 	}
 	for name, tc := range testCases {
-		name, tc := name, tc
 		t.Run(name, func(t *testing.T) {
 			t.Parallel()
 			id, err := trustgrpc.RequestToTRCQuery(tc.Input)
@@ -136,7 +135,6 @@ func TestChainsToRep(t *testing.T) {
 		},
 	}
 	for name, tc := range testCases {
-		name, tc := name, tc
 		t.Run(name, func(t *testing.T) {
 			t.Parallel()
 			chains := trustgrpc.ChainsToResponse(tc.Input)

control/trust/signer_gen_test.go

@@ -194,7 +194,6 @@ func TestChachingSignerGen(t *testing.T) {
 		},
 	}
 	for name, tc := range testCases {
-		name, tc := name, tc
 		t.Run(name, func(t *testing.T) {
 			t.Parallel()
 			mctrl := gomock.NewController(t)

daemon/daemon_test.go

@@ -49,7 +49,6 @@ func TestAPIAddress(t *testing.T) {
 		},
 	}
 	for name, tc := range testCases {
-		name, tc := name, tc
 		t.Run(name, func(t *testing.T) {
 			t.Parallel()
 			addr := daemon.APIAddress(tc.Input)

gateway/control/configpublisher.go

@@ -48,7 +48,6 @@ func (n *ConfigPublisher) Publish(sp SessionPolicies, rp *routing.Policy) {
 		n.sessionPolicies = sp.Copy()
 		wg.Add(len(n.sessionPoliciesSubscribers))
 		for _, c := range n.sessionPoliciesSubscribers {
-			c := c
 			go func() {
 				defer log.HandlePanic()
 				defer wg.Done()
@@ -57,7 +56,6 @@ func (n *ConfigPublisher) Publish(sp SessionPolicies, rp *routing.Policy) {
 		}
 		wg.Add(len(n.remoteIAsSubscribers))
 		for _, c := range n.remoteIAsSubscribers {
-			c := c
 			go func() {
 				defer log.HandlePanic()
 				defer wg.Done()
@@ -69,7 +67,6 @@ func (n *ConfigPublisher) Publish(sp SessionPolicies, rp *routing.Policy) {
 		n.routingPolicy = rp.Copy()
 		wg.Add(len(n.routingPoliciesSubscribers))
 		for _, c := range n.routingPoliciesSubscribers {
-			c := c
 			go func() {
 				defer log.HandlePanic()
 				defer wg.Done()

gateway/control/enginecontroller_test.go

@@ -544,7 +544,6 @@ func TestBuildRoutingChains(t *testing.T) {
 		},
 	}
 	for name, tc := range testCases {
-		name, tc := name, tc
 		t.Run(name, func(t *testing.T) {
 			chains, sm := control.BuildRoutingChains(tc.Input)
 			assert.Equal(t, tc.Chains, chains)

gateway/control/export_test.go

@@ -30,8 +30,10 @@ var (
 	BuildRoutingChains = buildRoutingChains
 )
 
-type ConjunctionPathPol = conjuctionPathPol
-type Diff = diff
+type (
+	ConjunctionPathPol = conjuctionPathPol
+	Diff               = diff
+)
 
 func (w *GatewayWatcher) RunOnce(ctx context.Context) {
 	w.run(ctx)
@@ -40,7 +42,6 @@ func (w *GatewayWatcher) RunOnce(ctx context.Context) {
 func (w *GatewayWatcher) RunAllPrefixWatchersOnceForTest(ctx context.Context) error {
 	var eg errgroup.Group
 	for _, wi := range w.currentWatchers {
-		wi := wi
 		wi.prefixWatcher.resetRunMarker()
 		eg.Go(func() error {
 			return wi.prefixWatcher.Run(ctx)

gateway/control/grpc/prefix_server_test.go

@@ -96,7 +96,6 @@ func TestIPPrefixServerPrefixes(t *testing.T) {
 		},
 	}
 	for name, tc := range testCases {
-		name, tc := name, tc
 		t.Run(name, func(t *testing.T) {
 			ctrl := gomock.NewController(t)
 			defer ctrl.Finish()

gateway/control/grpc/probeserver_test.go

@@ -58,7 +58,6 @@ func TestControlDispatcher(t *testing.T) {
 
 	conn := mock_net.NewMockPacketConn(ctrl)
 	for _, raw := range requests {
-		raw := raw
 		conn.EXPECT().ReadFrom(gomock.Any()).DoAndReturn(
 			func(buf []byte) (int, net.Addr, error) {
 				copy(buf, raw)
@@ -67,7 +66,6 @@ func TestControlDispatcher(t *testing.T) {
 		)
 	}
 	for _, raw := range requests[:3] {
-		raw := raw
 		// Use the fact that protobuf serializes this to the same wire format.
 		conn.EXPECT().WriteTo(raw, src)
 	}
@@ -96,5 +94,4 @@ func TestControlDispatcher(t *testing.T) {
 
 	// Make sure that the dispatcher shuts down.
 	<-done
-
 }

gateway/control/prefixesfilter_test.go

@@ -168,7 +168,6 @@ accept    1-ff00:0:113    1-ff00:0:110    10.3.0.0/25`))
 		},
 	}
 	for name, tc := range testCases {
-		name, tc := name, tc
 		t.Run(name, func(t *testing.T) {
 			t.Parallel()
 			ctrl := gomock.NewController(t)

gateway/control/remotemonitor.go

@@ -120,7 +120,6 @@ func (rm *RemoteMonitor) process(ctx context.Context, ias []addr.IA) {
 	logger := log.FromCtx(ctx)
 	newWatchers := make(map[addr.IA]watcherEntry)
 	for _, ia := range ias {
-		ia := ia
 		we, ok := rm.currentWatchers[ia]
 		if ok {
 			// Watcher for the remote IA exists. Move it to the new map of

gateway/control/routemgr_test.go

@@ -88,7 +88,6 @@ func TestRouteString(t *testing.T) {
 	}
 
 	for name, tc := range testCases {
-		tc := tc
 		t.Run(name, func(t *testing.T) {
 			assert.Equal(t, tc.String, tc.Route.String())
 		})

gateway/control/sessionconfigurator_test.go

@@ -340,7 +340,6 @@ func TestBuildSessionConfigs(t *testing.T) {
 			},
 			RoutingUpdate: control.RemoteGateways{
 				Gateways: map[addr.IA][]control.RemoteGateway{
-
 					addr.MustParseIA("1-ff00:0:110"): {
 						{
 							Gateway: control.Gateway{
@@ -492,7 +491,6 @@ func TestBuildSessionConfigs(t *testing.T) {
 		},
 	}
 	for name, tc := range testCases {
-		name, tc := name, tc
 		t.Run(name, func(t *testing.T) {
 			t.Parallel()
 
@@ -650,7 +648,6 @@ func TestConjuctionPolicy(t *testing.T) {
 		},
 	}
 	for name, tc := range testCases {
-		name, tc := name, tc
 		t.Run(name, func(t *testing.T) {
 			pol := control.ConjunctionPathPol{Pol1: tc.Pol1, Pol2: tc.Pol2}
 			acceptedPaths := pol.Filter(tc.InputPaths)
@@ -723,7 +720,6 @@ func TestNewPathPolForEnteringAS(t *testing.T) {
 					},
 				},
 				path.Path{
-
 					Meta: snet.PathMetadata{
 						Interfaces: []snet.PathInterface{
 							{IA: addr.MustParseIA("1-ff00:0:112"), ID: 2},
@@ -776,7 +772,6 @@ func TestNewPathPolForEnteringAS(t *testing.T) {
 		},
 	}
 	for name, tc := range testCases {
-		name, tc := name, tc
 		t.Run(name, func(t *testing.T) {
 			t.Parallel()
 			pol := control.NewPathPolForEnteringAS(tc.IA, tc.Interfaces)

gateway/control/sessionpolicy_test.go

@@ -109,7 +109,6 @@ func TestLegacySessionPolicyAdapterParse(t *testing.T) {
 		},
 	}
 	for name, tc := range testCases {
-		name, tc := name, tc
 		t.Run(name, func(t *testing.T) {
 			parser := control.LegacySessionPolicyAdapter{}
 			p, err := parser.Parse(context.Background(), tc.Input)
@@ -164,7 +163,6 @@ func TestLoadSessionPolicies(t *testing.T) {
 		},
 	}
 	for name, tc := range testCases {
-		name, tc := name, tc
 		t.Run(name, func(t *testing.T) {
 			ctrl := gomock.NewController(t)
 			defer ctrl.Finish()
@@ -206,7 +204,6 @@ func TestSessionPoliciesRemoteIAs(t *testing.T) {
 		},
 	}
 	for name, tc := range testCases {
-		name, tc := name, tc
 		t.Run(name, func(t *testing.T) {
 			t.Parallel()
 			assert.ElementsMatch(t, tc.Expected, tc.Policies.RemoteIAs())