chore: get rid of xerrors

go 1.14 is now required anyways

Author: Stebalien

dht.go

@@ -16,7 +16,6 @@ import (
 	"github.com/libp2p/go-libp2p-core/routing"
 
 	"go.opencensus.io/tag"
-	"golang.org/x/xerrors"
 
 	"github.com/libp2p/go-libp2p-kad-dht/metrics"
 	opts "github.com/libp2p/go-libp2p-kad-dht/opts"
@@ -482,10 +481,10 @@ func (dht *IpfsDHT) Ping(ctx context.Context, p peer.ID) error {
 	req := pb.NewMessage(pb.Message_PING, nil, 0)
 	resp, err := dht.sendRequest(ctx, p, req)
 	if err != nil {
-		return xerrors.Errorf("sending request: %w", err)
+		return fmt.Errorf("sending request: %w", err)
 	}
 	if resp.Type != pb.Message_PING {
-		return xerrors.Errorf("got unexpected response type: %v", resp.Type)
+		return fmt.Errorf("got unexpected response type: %v", resp.Type)
 	}
 	return nil
 }

dht_test.go

@@ -19,8 +19,6 @@ import (
 	"github.com/multiformats/go-multihash"
 	"github.com/multiformats/go-multistream"
 
-	"golang.org/x/xerrors"
-
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 
@@ -1755,5 +1753,5 @@ func TestClientModeAtInit(t *testing.T) {
 	client := setupDHT(ctx, t, true)
 	pinger.Host().Peerstore().AddAddrs(client.PeerID(), client.Host().Addrs(), peerstore.AddressTTL)
 	err := pinger.Ping(context.Background(), client.PeerID())
-	assert.True(t, xerrors.Is(err, multistream.ErrNotSupported))
+	assert.True(t, errors.Is(err, multistream.ErrNotSupported))
 }

go.mod

@@ -29,5 +29,4 @@ require (
 	github.com/multiformats/go-multistream v0.1.1
 	github.com/stretchr/testify v1.5.1
 	go.opencensus.io v0.22.3
-	golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898
 )

go.sum

@@ -538,9 +538,8 @@ golang.org/x/tools v0.0.0-20190114222345-bf090417da8b/go.mod h1:n7NCudcB/nEzxVGm
 golang.org/x/tools v0.0.0-20190226205152-f727befe758c/go.mod h1:9Yl7xja0Znq3iFh3HoIrodX9oNMXvdceNzlUR8zjMvY=
 golang.org/x/tools v0.0.0-20190311212946-11955173bddd h1:/e+gpKk9r3dJobndpTytxS2gOy6m5uvpg+ISQoEcusQ=
 golang.org/x/tools v0.0.0-20190311212946-11955173bddd/go.mod h1:LCzVGOaR6xXOjkQ3onu1FJEFr0SW1gC7cKk1uF8kGRs=
+golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7 h1:9zdDQZ7Thm29KFXgAX/+yaf3eVbP7djjWp/dXAppNCc=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898 h1:/atklqdjdhuosWIl6AIbOeHJjicWYPqR9bpxqxYG2pA=
-golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 google.golang.org/appengine v1.1.0/go.mod h1:EbEs0AVv82hx2wNQdGPgUI5lhzA/G0D9YwlJXL52JkM=
 google.golang.org/appengine v1.4.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7/EB5XEv4=
 google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8/go.mod h1:JiN7NxoALGmiZfu7CAH4rXhgtRTLTxftemlI0sWmxmc=