Use github.com/pkg/errors

authentication.go

@@ -2,9 +2,9 @@ package pgproto3
 
 import (
 	"encoding/binary"
-	"fmt"
 
 	"github.com/jackc/pgx/pgio"
+	"github.com/pkg/errors"
 )
 
 const (
@@ -31,7 +31,7 @@ func (dst *Authentication) Decode(src []byte) error {
 	case AuthTypeMD5Password:
 		copy(dst.Salt[:], src[4:8])
 	default:
-		return fmt.Errorf("unknown authentication type: %d", dst.Type)
+		return errors.Errorf("unknown authentication type: %d", dst.Type)
 	}
 
 	return nil

backend.go

@@ -2,10 +2,10 @@ package pgproto3
 
 import (
 	"encoding/binary"
-	"fmt"
 	"io"
 
 	"github.com/jackc/pgx/chunkreader"
+	"github.com/pkg/errors"
 )
 
 type Backend struct {
@@ -88,7 +88,7 @@ func (b *Backend) Receive() (FrontendMessage, error) {
 	case 'X':
 		msg = &b.terminate
 	default:
-		return nil, fmt.Errorf("unknown message type: %c", msgType)
+		return nil, errors.Errorf("unknown message type: %c", msgType)
 	}
 
 	msgBody, err := b.cr.Next(bodyLen)

frontend.go

@@ -2,10 +2,10 @@ package pgproto3
 
 import (
 	"encoding/binary"
-	"fmt"
 	"io"
 
 	"github.com/jackc/pgx/chunkreader"
+	"github.com/pkg/errors"
 )
 
 type Frontend struct {
@@ -100,7 +100,7 @@ func (b *Frontend) Receive() (BackendMessage, error) {
 	case 'Z':
 		msg = &b.readyForQuery
 	default:
-		return nil, fmt.Errorf("unknown message type: %c", msgType)
+		return nil, errors.Errorf("unknown message type: %c", msgType)
 	}
 
 	msgBody, err := b.cr.Next(bodyLen)

startup_message.go

@@ -4,9 +4,9 @@ import (
 	"bytes"
 	"encoding/binary"
 	"encoding/json"
-	"fmt"
 
 	"github.com/jackc/pgx/pgio"
+	"github.com/pkg/errors"
 )
 
 const (
@@ -23,18 +23,18 @@ func (*StartupMessage) Frontend() {}
 
 func (dst *StartupMessage) Decode(src []byte) error {
 	if len(src) < 4 {
-		return fmt.Errorf("startup message too short")
+		return errors.Errorf("startup message too short")
 	}
 
 	dst.ProtocolVersion = binary.BigEndian.Uint32(src)
 	rp := 4
 
 	if dst.ProtocolVersion == sslRequestNumber {
-		return fmt.Errorf("can't handle ssl connection request")
+		return errors.Errorf("can't handle ssl connection request")
 	}
 
 	if dst.ProtocolVersion != ProtocolVersionNumber {
-		return fmt.Errorf("Bad startup message version number. Expected %d, got %d", ProtocolVersionNumber, dst.ProtocolVersion)
+		return errors.Errorf("Bad startup message version number. Expected %d, got %d", ProtocolVersionNumber, dst.ProtocolVersion)
 	}
 
 	dst.Parameters = make(map[string]string)
@@ -57,7 +57,7 @@ func (dst *StartupMessage) Decode(src []byte) error {
 
 		if len(src[rp:]) == 1 {
 			if src[rp] != 0 {
-				return fmt.Errorf("Bad startup message last byte. Expected 0, got %d", src[rp])
+				return errors.Errorf("Bad startup message last byte. Expected 0, got %d", src[rp])
 			}
 			break
 		}