Add errorlint linter

.golangci.yml

@@ -12,6 +12,7 @@ linters:
   enable:
     - depguard
     - errcheck
+    - errorlint
     - godot
     - gofumpt
     - goimports

config/metric.go

@@ -262,7 +262,7 @@ func prometheusReader(ctx context.Context, prometheusConfig *Prometheus) (sdkmet
 	}
 
 	go func() {
-		if err := server.Serve(lis); err != nil && err != http.ErrServerClosed {
+		if err := server.Serve(lis); err != nil && errors.Is(err, http.ErrServerClosed) {
 			otel.Handle(fmt.Errorf("the Prometheus HTTP server exited unexpectedly: %w", err))
 		}
 	}()

detectors/aws/ec2/ec2.go

@@ -5,6 +5,7 @@ package ec2 // import "go.opentelemetry.io/contrib/detectors/aws/ec2"
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"net/http"
 
@@ -139,7 +140,8 @@ func (m *metadata) add(k attribute.Key, n string) {
 		return
 	}
 
-	rf, ok := err.(awserr.RequestFailure)
+	var rf awserr.RequestFailure
+	ok := errors.As(err, &rf)
 	if !ok {
 		m.errs = append(m.errs, fmt.Errorf("%q: %w", n, err))
 		return

detectors/gcp/cloud-function_test.go

@@ -134,7 +134,7 @@ func TestCloudFunctionDetect(t *testing.T) {
 			cloudRun: test.cr,
 		}
 		res, err := detector.Detect(context.Background())
-		if err != test.expected.err {
+		if !errors.Is(err, test.expected.err) {
 			t.Fatalf("got unexpected failure: %v", err)
 		} else if diff := cmp.Diff(test.expected.res, res); diff != "" {
 			t.Errorf("detected resource differ from expected (-want, +got)\n%s", diff)

detectors/gcp/gce.go

@@ -5,6 +5,7 @@ package gcp // import "go.opentelemetry.io/contrib/detectors/gcp"
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"os"
 	"strings"
@@ -90,7 +91,9 @@ func hasProblem(err error) bool {
 	if err == nil {
 		return false
 	}
-	if _, undefined := err.(metadata.NotDefinedError); undefined {
+
+	var nde metadata.NotDefinedError
+	if undefined := errors.As(err, &nde); undefined {
 		return false
 	}
 	return true

exporters/autoexport/metrics.go

@@ -193,7 +193,7 @@ func init() {
 		}
 
 		go func() {
-			if err := server.Serve(lis); err != nil && err != http.ErrServerClosed {
+			if err := server.Serve(lis); err != nil && !errors.Is(err, http.ErrServerClosed) {
 				otel.Handle(fmt.Errorf("the Prometheus HTTP server exited unexpectedly: %w", err))
 			}
 		}()

instrumentation/google.golang.org/grpc/otelgrpc/example/client/main.go

@@ -5,6 +5,7 @@
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"io"
 	"log"
@@ -121,7 +122,7 @@
 
 	for {
 		response, err := stream.Recv()
-		if err == io.EOF {
+		if errors.Is(err, io.EOF) {
 			break
 		} else if err != nil {
 			return fmt.Errorf("receiving from SayHelloServerStream: %w", err)
@@ -172,7 +173,7 @@
 	go func() {
 		for {
 			response, err := stream.Recv()
-			if err == io.EOF {
+			if errors.Is(err, io.EOF) {
 				break
 			} else if err != nil {
 				// nolint: revive  // This acts as its own main func.

instrumentation/google.golang.org/grpc/otelgrpc/example/server/main.go

@@ -5,6 +5,7 @@
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"io"
 	"log"
@@ -68,7 +69,7 @@
 	for {
 		in, err := stream.Recv()
 
-		if err == io.EOF {
+		if errors.Is(err, io.EOF) {
 			break
 		} else if err != nil {
 			log.Printf("Non EOF error: %v\n", err)
@@ -88,7 +89,7 @@
 	for {
 		in, err := stream.Recv()
 
-		if err == io.EOF {
+		if errors.Is(err, io.EOF) {
 			break
 		} else if err != nil {
 			log.Printf("Non EOF error: %v\n", err)

instrumentation/google.golang.org/grpc/otelgrpc/interceptor.go

@@ -7,6 +7,7 @@ package otelgrpc // import "go.opentelemetry.io/contrib/instrumentation/google.g
 // https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/trace/semantic_conventions/rpc.md
 import (
 	"context"
+	"errors"
 	"io"
 	"net"
 	"strconv"
@@ -136,7 +137,7 @@ func (w *clientStream) RecvMsg(m interface{}) error {
 
 	if err == nil && !w.desc.ServerStreams {
 		w.endSpan(nil)
-	} else if err == io.EOF {
+	} else if errors.Is(err, io.EOF) {
 		w.endSpan(nil)
 	} else if err != nil {
 		w.endSpan(err)

instrumentation/google.golang.org/grpc/otelgrpc/internal/test/test_utils.go

@@ -28,6 +28,7 @@
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"io"
 	"time"
@@ -162,7 +163,7 @@
 		index++
 		respCnt++
 	}
-	if rpcStatus != io.EOF {
+	if !errors.Is(rpcStatus, io.EOF) {
 		logger.Fatalf("Failed to finish the server streaming rpc: %v", rpcStatus)
 	}
 	if respCnt != len(respSizes) {
@@ -209,7 +210,7 @@
 	if err := stream.CloseSend(); err != nil {
 		logger.Fatalf("%v.CloseSend() got %v, want %v", stream, err, nil)
 	}
-	if _, err := stream.Recv(); err != io.EOF {
+	if _, err := stream.Recv(); !errors.Is(err, io.EOF) {
 		logger.Fatalf("%v failed to complele the ping pong test: %v", stream, err)
 	}
 }
@@ -223,7 +224,7 @@
 	if err := stream.CloseSend(); err != nil {
 		logger.Fatalf("%v.CloseSend() got %v, want %v", stream, err, nil)
 	}
-	if _, err := stream.Recv(); err != io.EOF {
+	if _, err := stream.Recv(); !errors.Is(err, io.EOF) {
 		logger.Fatalf("%v failed to complete the empty stream test: %v", stream, err)
 	}
 }
@@ -306,7 +307,7 @@
 	var sum int
 	for {
 		in, err := stream.Recv()
-		if err == io.EOF {
+		if errors.Is(err, io.EOF) {
 			return stream.SendAndClose(&testpb.StreamingInputCallResponse{
 				AggregatedPayloadSize: int32(sum),
 			})
@@ -332,7 +333,7 @@
 	}
 	for {
 		in, err := stream.Recv()
-		if err == io.EOF {
+		if errors.Is(err, io.EOF) {
 			// read done.
 			return nil
 		}
@@ -366,7 +367,7 @@
 	var msgBuf []*testpb.StreamingOutputCallRequest
 	for {
 		in, err := stream.Recv()
-		if err == io.EOF {
+		if errors.Is(err, io.EOF) {
 			// read done.
 			break
 		}

instrumentation/google.golang.org/grpc/otelgrpc/test/grpc_stats_handler_test.go

@@ -5,6 +5,7 @@ package test
 
 import (
 	"context"
+	"errors"
 	"io"
 	"net"
 	"strconv"
@@ -1438,7 +1439,7 @@ func TestStatsHandlerConcurrentSafeContextCancellation(t *testing.T) {
 					Payload:            pl,
 				}
 				err := stream.Send(req)
-				if err == io.EOF { // possible due to context cancellation
+				if errors.Is(err, io.EOF) { // possible due to context cancellation
 					require.ErrorIs(t, ctx.Err(), context.Canceled)
 				} else {
 					require.NoError(t, err)

instrumentation/net/http/otelhttp/internal/semconv/v1.20.0.go

@@ -4,6 +4,7 @@
 package semconv // import "go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp/internal/semconv"
 
 import (
+	"errors"
 	"io"
 	"net/http"
 
@@ -43,7 +44,7 @@ func (o oldHTTPServer) ResponseTraceAttrs(resp ResponseTelemetry) []attribute.Ke
 	if resp.ReadBytes > 0 {
 		attributes = append(attributes, semconv.HTTPRequestContentLength(int(resp.ReadBytes)))
 	}
-	if resp.ReadError != nil && resp.ReadError != io.EOF {
+	if resp.ReadError != nil && !errors.Is(resp.ReadError, io.EOF) {
 		// This is not in the semantic conventions, but is historically provided
 		attributes = append(attributes, attribute.String("http.read_error", resp.ReadError.Error()))
 	}
@@ -53,7 +54,7 @@ func (o oldHTTPServer) ResponseTraceAttrs(resp ResponseTelemetry) []attribute.Ke
 	if resp.StatusCode > 0 {
 		attributes = append(attributes, semconv.HTTPStatusCode(resp.StatusCode))
 	}
-	if resp.WriteError != nil && resp.WriteError != io.EOF {
+	if resp.WriteError != nil && !errors.Is(resp.WriteError, io.EOF) {
 		// This is not in the semantic conventions, but is historically provided
 		attributes = append(attributes, attribute.String("http.write_error", resp.WriteError.Error()))
 	}