Replace go-check with testify

It's muuuuch better.

client_test.go

@@ -17,7 +17,6 @@ import (
 	"github.com/bradfitz/iter"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
-	"gopkg.in/check.v1"
 
 	"github.com/anacrolix/torrent/bencode"
 	"github.com/anacrolix/torrent/data"
@@ -308,21 +307,21 @@ func TestReadaheadPieces(t *testing.T) {
 	}
 }
 
-func (suite) TestMergingTrackersByAddingSpecs(c *check.C) {
+func TestMergingTrackersByAddingSpecs(t *testing.T) {
 	cl, _ := NewClient(&TestingConfig)
 	defer cl.Close()
 	spec := TorrentSpec{}
 	T, new, _ := cl.AddTorrentSpec(&spec)
 	if !new {
-		c.FailNow()
+		t.FailNow()
 	}
 	spec.Trackers = [][]string{{"http://a"}, {"udp://b"}}
 	_, new, _ = cl.AddTorrentSpec(&spec)
 	if new {
-		c.FailNow()
+		t.FailNow()
 	}
-	c.Assert(T.Trackers[0][0].URL(), check.Equals, "http://a")
-	c.Assert(T.Trackers[1][0].URL(), check.Equals, "udp://b")
+	assert.EqualValues(t, T.Trackers[0][0].URL(), "http://a")
+	assert.EqualValues(t, T.Trackers[1][0].URL(), "udp://b")
 }
 
 type badData struct {

connection_test.go

@@ -5,7 +5,7 @@ import (
 	"time"
 
 	"github.com/bradfitz/iter"
-	. "gopkg.in/check.v1"
+	"github.com/stretchr/testify/assert"
 
 	"github.com/anacrolix/torrent/internal/pieceordering"
 	"github.com/anacrolix/torrent/peer_protocol"
@@ -60,18 +60,12 @@ func pieceOrderingAsSlice(po *pieceordering.Instance) (ret []int) {
 	return
 }
 
-func testRequestOrder(expected []int, ro *pieceordering.Instance, t *C) {
-	t.Assert(pieceOrderingAsSlice(ro), DeepEquals, expected)
+func testRequestOrder(expected []int, ro *pieceordering.Instance, t *testing.T) {
+	assert.EqualValues(t, pieceOrderingAsSlice(ro), expected)
 }
 
-type suite struct{}
-
-var _ = Suite(suite{})
-
-func Test(t *testing.T) { TestingT(t) }
-
 // Tests the request ordering based on a connections priorities.
-func (suite) TestPieceRequestOrder(t *C) {
+func TestPieceRequestOrder(t *testing.T) {
 	c := connection{
 		pieceRequestOrder: pieceordering.New(),
 		piecePriorities:   []int{1, 4, 0, 3, 2},

misc_test.go

@@ -1,12 +1,16 @@
 package torrent
 
-import . "gopkg.in/check.v1"
+import (
+	"testing"
 
-func (suite) TestTorrentOffsetRequest(c *C) {
+	"github.com/stretchr/testify/assert"
+)
+
+func TestTorrentOffsetRequest(t *testing.T) {
 	check := func(tl, ps, off int64, expected request, ok bool) {
 		req, _ok := torrentOffsetRequest(tl, ps, defaultChunkSize, off)
-		c.Check(_ok, Equals, ok)
-		c.Check(req, Equals, expected)
+		assert.Equal(t, _ok, ok)
+		assert.Equal(t, req, expected)
 	}
 	check(13, 5, 0, newRequest(0, 0, 5), true)
 	check(13, 5, 3, newRequest(0, 0, 5), true)