chore: enable modernize linter (#8583)

mmorel-35 · pellared · MrAlias · web-flow · commit 22248d4c3163 · 2026-03-05T11:54:07.000-08:00
Signed-off-by: Matthieu MOREL &lt;matthieu.morel35@gmail.com&gt;
Co-authored-by: Robert Pająk &lt;pellared@hotmail.com&gt;
Co-authored-by: Tyler Yahn &lt;codingalias@gmail.com&gt;
diff --git a/.golangci.yml b/.golangci.yml
@@ -18,6 +18,7 @@ linters:
     - govet
     - ineffassign
     - intrange
+    - modernize
     - misspell
     - nolintlint
     - perfsprint
diff --git a/bridges/otelzap/core_test.go b/bridges/otelzap/core_test.go
@@ -187,16 +187,12 @@ func TestCoreWriteContextConcurrentSafe(t *testing.T) {
 	ctx = context.WithValue(ctx, testEntry, true)
 
 	var wg sync.WaitGroup
-	wg.Add(1)
-	go func() {
-		defer wg.Done()
+	wg.Go(func() {
 		logger.Debug(testMessage, zap.Any("ctx", ctx))
-	}()
-	wg.Add(1)
-	go func() {
-		defer wg.Done()
+	})
+	wg.Go(func() {
 		logger.Debug(testMessage, zap.Any("ctx", ctx))
-	}()
+	})
 	wg.Wait()
 
 	want := logtest.Recording{
diff --git a/detectors/aws/ecs/ecs.go b/detectors/aws/ecs/ecs.go
@@ -260,8 +260,8 @@ func (ecsDetectorUtils) getContainerName() (string, error) {
 }
 
 func getCgroupContainerID(fileData []byte) string {
-	splitData := strings.Split(strings.TrimSpace(string(fileData)), "\n")
-	for _, str := range splitData {
+	splitData := strings.SplitSeq(strings.TrimSpace(string(fileData)), "\n")
+	for str := range splitData {
 		if ecsCgroupPathPattern.MatchString(str) {
 			return str[len(str)-containerIDLength:]
 		}
diff --git a/detectors/aws/eks/detector.go b/detectors/aws/eks/detector.go
@@ -183,8 +183,8 @@ func (eksDetectorUtils) getContainerID() (string, error) {
 	}
 
 	// Retrieve containerID from file
-	splitData := strings.Split(strings.TrimSpace(string(fileData)), "\n")
-	for _, str := range splitData {
+	splitData := strings.SplitSeq(strings.TrimSpace(string(fileData)), "\n")
+	for str := range splitData {
 		if containerIDRegex.MatchString(str) {
 			return str[len(str)-containerIDLength:], nil
 		}
diff --git a/exporters/autoexport/metrics.go b/exporters/autoexport/metrics.go
@@ -295,7 +295,7 @@ func (pr producerRegistry) create(ctx context.Context) ([]metric.Producer, error
 
 func dedupedMetricProducers(envValue string) []string {
 	producers := make(map[string]struct{})
-	for _, producer := range strings.Split(envValue, ",") {
+	for producer := range strings.SplitSeq(envValue, ",") {
 		producers[producer] = struct{}{}
 	}
 
diff --git a/exporters/autoexport/registry_test.go b/exporters/autoexport/registry_test.go
@@ -46,18 +46,14 @@ func TestRegistryIsConcurrentSafe(t *testing.T) {
 
 	var wg sync.WaitGroup
 
-	wg.Add(1)
-	go func() {
-		defer wg.Done()
+	wg.Go(func() {
 		assert.ErrorIs(t, r.store(exporterName, factory("stdout")), errDuplicateRegistration)
-	}()
+	})
 
-	wg.Add(1)
-	go func() {
-		defer wg.Done()
+	wg.Go(func() {
 		_, err := r.load(t.Context(), exporterName)
 		assert.NoError(t, err, "missing exporter in registry")
-	}()
+	})
 
 	wg.Wait()
 }
diff --git a/instrumentation/github.com/aws/aws-lambda-go/otellambda/lambdatest_test.go b/instrumentation/github.com/aws/aws-lambda-go/otellambda/lambdatest_test.go
@@ -351,7 +351,7 @@ func mockRequestCarrier(eventJSON []byte) propagation.TextMapCarrier {
 	var event mockRequest
 	err := json.Unmarshal(eventJSON, &event)
 	if err != nil {
-		fmt.Println("event type: ", reflect.TypeOf(event))
+		fmt.Println("event type: ", reflect.TypeFor[mockRequest]())
 		panic("mockRequestCarrier only supports events of type mockRequest")
 	}
 	return propagation.HeaderCarrier{mockPropagatorKey: []string{event.Headers[mockPropagatorKey]}}
@@ -361,10 +361,10 @@ func mockTraceAttributeFn(eventJSON []byte) []attribute.KeyValue {
 	var event mockRequest
 	err := json.Unmarshal(eventJSON, &event)
 	if err != nil {
-		fmt.Println("event type: ", reflect.TypeOf(event))
+		fmt.Println("event type: ", reflect.TypeFor[mockRequest]())
 		panic("mockRequestCarrier only supports events of type mockRequest")
 	}
-	return []attribute.KeyValue{attribute.String("mock.request.type", reflect.TypeOf(event).String())}
+	return []attribute.KeyValue{attribute.String("mock.request.type", reflect.TypeFor[mockRequest]().String())}
 }
 
 func TestInstrumentHandlerTracingWithMockPropagator(t *testing.T) {
@@ -427,6 +427,6 @@ func TestWrapHandlerTracingWithTraceAttributeFn(t *testing.T) {
 
 	assert.Len(t, memExporter.GetSpans(), 1)
 	stub := memExporter.GetSpans()[0]
-	expectedAttr := attribute.KeyValue{Key: "mock.request.type", Value: attribute.StringValue(reflect.TypeOf(mockPropagatorTestsEvent).String())}
+	expectedAttr := attribute.KeyValue{Key: "mock.request.type", Value: attribute.StringValue(reflect.TypeFor[mockRequest]().String())}
 	assert.Contains(t, stub.Attributes, expectedAttr, "custom attribute 'mock.request.type' with value 'otellambda_test.mockRequest' not found")
 }
diff --git a/instrumentation/github.com/aws/aws-lambda-go/otellambda/wrapLambdaHandler.go b/instrumentation/github.com/aws/aws-lambda-go/otellambda/wrapLambdaHandler.go
@@ -30,7 +30,7 @@ func validateArguments(handler reflect.Type) (bool, error) {
 	if handler.NumIn() > 2 {
 		return false, fmt.Errorf("handlers may not take more than two arguments, but handler takes %d", handler.NumIn())
 	} else if handler.NumIn() > 0 {
-		contextType := reflect.TypeOf((*context.Context)(nil)).Elem()
+		contextType := reflect.TypeFor[context.Context]()
 		argumentType := handler.In(0)
 		handlerTakesContext = argumentType.Implements(contextType)
 		if handler.NumIn() > 1 && !handlerTakesContext {
@@ -44,7 +44,7 @@ func validateArguments(handler reflect.Type) (bool, error) {
 // Ensure handler returns 0-2 values, with an error
 // as its first value if any exist.
 func validateReturns(handler reflect.Type) error {
-	errorType := reflect.TypeOf((*error)(nil)).Elem()
+	errorType := reflect.TypeFor[error]()
 
 	switch n := handler.NumOut(); {
 	case n > 2:
diff --git a/instrumentation/github.com/aws/aws-lambda-go/otellambda/xrayconfig/collector_test.go b/instrumentation/github.com/aws/aws-lambda-go/otellambda/xrayconfig/collector_test.go
@@ -8,6 +8,7 @@ package xrayconfig
 
 import (
 	"sort"
+	"strings"
 
 	collectortracepb "go.opentelemetry.io/proto/otlp/collector/trace/v1"
 	commonpb "go.opentelemetry.io/proto/otlp/common/v1"
@@ -72,11 +73,11 @@ func (s *SpansStorage) GetResourceSpans() []*tracepb.ResourceSpans {
 
 func resourceString(res *resourcepb.Resource) string {
 	sAttrs := sortedAttributes(res.GetAttributes())
-	rstr := ""
-	for _, attr := range sAttrs {
-		rstr += attr.String()
+	strs := make([]string, len(sAttrs))
+	for i, attr := range sAttrs {
+		strs[i] = attr.String()
 	}
-	return rstr
+	return strings.Join(strs, "")
 }
 
 func sortedAttributes(attrs []*commonpb.KeyValue) []*commonpb.KeyValue {
diff --git a/instrumentation/go.mongodb.org/mongo-driver/mongo/otelmongo/internal/semconv/event_monitor.go b/instrumentation/go.mongodb.org/mongo-driver/mongo/otelmongo/internal/semconv/event_monitor.go
@@ -65,7 +65,7 @@ func WithCommandAttributeDisabled(disabled bool) AttributeOption {
 // hasOptIn returns true if the comma-separated version string contains the
 // exact optIn value.
 func hasOptIn(version, optIn string) bool {
-	for _, v := range strings.Split(version, ",") {
+	for v := range strings.SplitSeq(version, ",") {
 		if strings.TrimSpace(v) == optIn {
 			return true
 		}
diff --git a/instrumentation/go.mongodb.org/mongo-driver/v2/mongo/otelmongo/metrics_test.go b/instrumentation/go.mongodb.org/mongo-driver/v2/mongo/otelmongo/metrics_test.go
@@ -32,7 +32,7 @@ func TestMetricsOperationDuration(t *testing.T) {
 	defer cancel()
 
 	opts := options.Client()
-	opts.Deployment = md //nolint:staticcheck // This method is the current documented way to set the mongodb mock. See https://github.com/mongodb/mongo-go-driver/blob/v2.0.0/x/mongo/driver/drivertest/opmsg_deployment_test.go#L24
+	opts.Deployment = md //nolint:staticcheck  // This method is the current documented way to set the mongodb mock. See https://github.com/mongodb/mongo-go-driver/blob/v2.0.0/x/mongo/driver/drivertest/opmsg_deployment_test.go#L24
 	opts.Monitor = NewMonitor(
 		WithMeterProvider(provider),
 		WithCommandAttributeDisabled(false),
@@ -101,7 +101,7 @@ func TestMetricsOperationFailure(t *testing.T) {
 	defer cancel()
 
 	opts := options.Client()
-	opts.Deployment = md //nolint:staticcheck // This method is the current documented way to set the mongodb mock. See https://github.com/mongodb/mongo-go-driver/blob/v2.0.0/x/mongo/driver/drivertest/opmsg_deployment_test.go#L24
+	opts.Deployment = md //nolint:staticcheck  // This method is the current documented way to set the mongodb mock. See https://github.com/mongodb/mongo-go-driver/blob/v2.0.0/x/mongo/driver/drivertest/opmsg_deployment_test.go#L24
 	opts.Monitor = NewMonitor(
 		WithMeterProvider(provider),
 		WithCommandAttributeDisabled(true),
diff --git a/instrumentation/go.mongodb.org/mongo-driver/v2/mongo/otelmongo/mongo_test.go b/instrumentation/go.mongodb.org/mongo-driver/v2/mongo/otelmongo/mongo_test.go
@@ -66,7 +66,7 @@ func TestWithSpanNameFormatter(t *testing.T) {
 			ctx, span := provider.Tracer("test").Start(ctx, "mongodb-test")
 			addr := "mongodb://localhost:27017/?connect=direct"
 			opts := options.Client()
-			opts.Deployment = md //nolint:staticcheck // This method is the current documented way to set the mongodb mock. See https://github.com/mongodb/mongo-go-driver/blob/v2.0.0/x/mongo/driver/drivertest/opmsg_deployment_test.go#L24
+			opts.Deployment = md //nolint:staticcheck  // This method is the current documented way to set the mongodb mock. See https://github.com/mongodb/mongo-go-driver/blob/v2.0.0/x/mongo/driver/drivertest/opmsg_deployment_test.go#L24
 			opts.Monitor = NewMonitor(
 				WithTracerProvider(provider),
 				WithSpanNameFormatter(tc.SpanNameFormatter),
@@ -170,7 +170,7 @@ func TestDBCrudOperation(t *testing.T) {
 
 			addr := "mongodb://localhost:27017/?connect=direct"
 			opts := options.Client()
-			opts.Deployment = md //nolint:staticcheck // This method is the current documented way to set the mongodb mock. See https://github.com/mongodb/mongo-go-driver/blob/v2.0.0/x/mongo/driver/drivertest/opmsg_deployment_test.go#L24
+			opts.Deployment = md //nolint:staticcheck  // This method is the current documented way to set the mongodb mock. See https://github.com/mongodb/mongo-go-driver/blob/v2.0.0/x/mongo/driver/drivertest/opmsg_deployment_test.go#L24
 			opts.Monitor = NewMonitor(
 				WithTracerProvider(provider),
 				WithCommandAttributeDisabled(tc.excludeCommand),
@@ -278,7 +278,7 @@ func TestDBCollectionAttribute(t *testing.T) {
 
 			addr := "mongodb://localhost:27017/?connect=direct"
 			opts := options.Client()
-			opts.Deployment = md //nolint:staticcheck // This method is the current documented way to set the mongodb mock. See https://github.com/mongodb/mongo-go-driver/blob/v2.0.0/x/mongo/driver/drivertest/opmsg_deployment_test.go#L24
+			opts.Deployment = md //nolint:staticcheck  // This method is the current documented way to set the mongodb mock. See https://github.com/mongodb/mongo-go-driver/blob/v2.0.0/x/mongo/driver/drivertest/opmsg_deployment_test.go#L24
 			opts.Monitor = NewMonitor(
 				WithTracerProvider(provider),
 				WithCommandAttributeDisabled(true),
diff --git a/instrumentation/google.golang.org/grpc/otelgrpc/grpc_stats_handler_test.go b/instrumentation/google.golang.org/grpc/otelgrpc/grpc_stats_handler_test.go
@@ -445,9 +445,7 @@ func TestStatsHandlerConcurrentSafeContextCancellation(t *testing.T) {
 		const messageCount = 10
 		var wg sync.WaitGroup
 
-		wg.Add(1)
-		go func() {
-			defer wg.Done()
+		wg.Go(func() {
 			for range messageCount {
 				const reqSize = 1
 				pl := test.ClientNewPayload(testpb.PayloadType_COMPRESSABLE, reqSize)
@@ -469,11 +467,9 @@ func TestStatsHandlerConcurrentSafeContextCancellation(t *testing.T) {
 				}
 			}
 			assert.NoError(t, stream.CloseSend())
-		}()
+		})
 
-		wg.Add(1)
-		go func() {
-			defer wg.Done()
+		wg.Go(func() {
 			for i := range messageCount {
 				_, err := stream.Recv()
 				if i > messageCount/2 {
@@ -485,7 +481,7 @@ func TestStatsHandlerConcurrentSafeContextCancellation(t *testing.T) {
 				}
 				assert.NoError(t, err)
 			}
-		}()
+		})
 
 		wg.Wait()
 	}
diff --git a/otelconf/config_common.go b/otelconf/config_common.go
@@ -142,12 +142,9 @@ func (e *errInvalid) Error() string {
 	return "invalid config: " + e.Identifier
 }
 
-func (e *errInvalid) Is(target error) bool {
-	t, ok := target.(*errInvalid)
-	if !ok {
-		return false
-	}
-	return reflect.TypeOf(e.Identifier) == reflect.TypeOf(t.Identifier)
+func (*errInvalid) Is(target error) bool {
+	_, ok := target.(*errInvalid)
+	return ok
 }
 
 // newErrInvalid creates a new error indicating that an error occurred due to misconfiguration.
diff --git a/otelconf/internal/provider/envprovider.go b/otelconf/internal/provider/envprovider.go
@@ -101,8 +101,8 @@ type defaultValue struct {
 func parseEnvVar(in string) (string, defaultValue) {
 	in = strings.TrimPrefix(in, "env:")
 	const sep = ":-"
-	if i := strings.Index(in, sep); i >= 0 {
-		return in[:i], defaultValue{data: in[i+len(sep):], valid: true}
+	if before, after, ok := strings.Cut(in, sep); ok {
+		return before, defaultValue{data: after, valid: true}
 	}
 	return in, defaultValue{}
 }
diff --git a/otelconf/propagator.go b/otelconf/propagator.go
@@ -45,7 +45,7 @@ func newPropagator(p *Propagator) (propagation.TextMapPropagator, error) {
 	}
 
 	if p.CompositeList != nil {
-		for _, v := range strings.Split(*p.CompositeList, ",") {
+		for v := range strings.SplitSeq(*p.CompositeList, ",") {
 			names[v] = struct{}{}
 		}
 	}
diff --git a/otelconf/v0.3.0/fuzz_test.go b/otelconf/v0.3.0/fuzz_test.go
@@ -8,6 +8,7 @@ import (
 	"encoding/json"
 	"os"
 	"path/filepath"
+	"slices"
 	"testing"
 	"time"
 
@@ -76,12 +77,7 @@ func FuzzYAMLWithEnvVars(f *testing.F) {
 		// Helper function to check if environment variable value is valid.
 		isValidEnvValue := func(value string) bool {
 			// Environment variable values cannot contain null bytes.
-			for _, b := range []byte(value) {
-				if b == 0 {
-					return false
-				}
-			}
-			return true
+			return !slices.Contains([]byte(value), 0)
 		}
 
 		// Set environment variables used in the test YAML with fuzzed values.
diff --git a/processors/minsev/severity_test.go b/processors/minsev/severity_test.go
@@ -19,23 +19,19 @@ func TestSeverityVarConcurrentSafe(*testing.T) {
 		wg  sync.WaitGroup
 	)
 
-	wg.Add(1)
-	go func() {
-		defer wg.Done()
+	wg.Go(func() {
 		for s := SeverityTrace1; s <= SeverityFatal4; s++ {
 			sev.Set(s)
 		}
-	}()
+	})
 
-	wg.Add(1)
-	go func() {
-		defer wg.Done()
+	wg.Go(func() {
 		var got log.Severity
 		for i := SeverityFatal4 - SeverityTrace1; i >= 0; i-- {
 			got = sev.Severity()
 		}
 		_ = got
-	}()
+	})
 
 	wg.Wait()
 }
diff --git a/propagators/autoprop/registry_test.go b/propagators/autoprop/registry_test.go
@@ -41,23 +41,19 @@ func TestRegistryConcurrentSafe(t *testing.T) {
 
 	var wg sync.WaitGroup
 
-	wg.Add(1)
-	go func() {
-		defer wg.Done()
+	wg.Go(func() {
 		assert.NotPanics(t, func() {
 			require.ErrorIs(t, r.store(propName, noop), errDupReg)
 		})
-	}()
+	})
 
-	wg.Add(1)
-	go func() {
-		defer wg.Done()
+	wg.Go(func() {
 		assert.NotPanics(t, func() {
 			v, ok := r.load(propName)
 			assert.True(t, ok, "missing propagator in registry")
 			assert.Equal(t, noop, v, "wrong propagator returned")
 		})
-	}()
+	})
 
 	wg.Wait()
 }
diff --git a/propagators/aws/xray/propagator.go b/propagators/aws/xray/propagator.go
@@ -107,11 +107,11 @@ func extract(headerVal string) (trace.SpanContext, error) {
 			part = strings.TrimSpace(headerVal[pos:])
 			pos = len(headerVal)
 		}
-		equalsIndex := strings.Index(part, kvDelimiter)
-		if equalsIndex < 0 {
+		_, after, ok := strings.Cut(part, kvDelimiter)
+		if !ok {
 			return empty, errInvalidTraceHeader
 		}
-		value := part[equalsIndex+1:]
+		value := after
 		switch {
 		case strings.HasPrefix(part, traceIDKey):
 			scc.TraceID, err = parseTraceID(value)
diff --git a/samplers/jaegerremote/sampler_remote_options.go b/samplers/jaegerremote/sampler_remote_options.go
@@ -51,8 +51,8 @@ func getEnvOptions() ([]Option, []error) {
 		return nil, nil
 	}
 
-	args := strings.Split(rawEnvArgs, ",")
-	for _, arg := range args {
+	args := strings.SplitSeq(rawEnvArgs, ",")
+	for arg := range args {
 		keyValue := strings.Split(arg, "=")
 		if len(keyValue) != 2 {
 			errs = append(errs, fmt.Errorf("argument %s is not of type '<key>=<value>'", arg))
diff --git a/samplers/jaegerremote/sampler_remote_test.go b/samplers/jaegerremote/sampler_remote_test.go
diff --git a/samplers/probability/consistent/sampler_test.go b/samplers/probability/consistent/sampler_test.go
diff --git a/samplers/probability/consistent/tracestate.go b/samplers/probability/consistent/tracestate.go
diff --git a/zpages/tracez_test.go b/zpages/tracez_test.go

Original file line number	Diff line number	Diff line change
`@@ -260,8 +260,8 @@ func (ecsDetectorUtils) getContainerName() (string, error) {`
`260`	`260`	`}`
`261`	`261`
`262`	`262`	`func getCgroupContainerID(fileData []byte) string {`
`263`		`- splitData := strings.Split(strings.TrimSpace(string(fileData)), "\n")`
`264`		`- for _, str := range splitData {`
	`263`	`+ splitData := strings.SplitSeq(strings.TrimSpace(string(fileData)), "\n")`
	`264`	`+ for str := range splitData {`
`265`	`265`	`if ecsCgroupPathPattern.MatchString(str) {`
`266`	`266`	`return str[len(str)-containerIDLength:]`
`267`	`267`	`}`
Original file line number	Diff line number	Diff line change
`@@ -183,8 +183,8 @@ func (eksDetectorUtils) getContainerID() (string, error) {`
`183`	`183`	`}`
`184`	`184`
`185`	`185`	`// Retrieve containerID from file`
`186`		`- splitData := strings.Split(strings.TrimSpace(string(fileData)), "\n")`
`187`		`- for _, str := range splitData {`
	`186`	`+ splitData := strings.SplitSeq(strings.TrimSpace(string(fileData)), "\n")`
	`187`	`+ for str := range splitData {`
`188`	`188`	`if containerIDRegex.MatchString(str) {`
`189`	`189`	`return str[len(str)-containerIDLength:], nil`
`190`	`190`	`}`
Original file line number	Diff line number	Diff line change
`@@ -295,7 +295,7 @@ func (pr producerRegistry) create(ctx context.Context) ([]metric.Producer, error`
`295`	`295`
`296`	`296`	`func dedupedMetricProducers(envValue string) []string {`
`297`	`297`	`producers := make(map[string]struct{})`
`298`		`- for _, producer := range strings.Split(envValue, ",") {`
	`298`	`+ for producer := range strings.SplitSeq(envValue, ",") {`
`299`	`299`	`producers[producer] = struct{}{}`
`300`	`300`	`}`
`301`	`301`
Original file line number	Diff line number	Diff line change
`@@ -65,7 +65,7 @@ func WithCommandAttributeDisabled(disabled bool) AttributeOption {`
`65`	`65`	`// hasOptIn returns true if the comma-separated version string contains the`
`66`	`66`	`// exact optIn value.`
`67`	`67`	`func hasOptIn(version, optIn string) bool {`
`68`		`- for _, v := range strings.Split(version, ",") {`
	`68`	`+ for v := range strings.SplitSeq(version, ",") {`
`69`	`69`	`if strings.TrimSpace(v) == optIn {`
`70`	`70`	`return true`
`71`	`71`	`}`