Use iotest.TestReader

bad_storage.go

@@ -5,6 +5,7 @@ import (
 	"math/rand"
 	"strings"
 
+	"github.com/anacrolix/torrent/internal/testutil"
 	"github.com/anacrolix/torrent/metainfo"
 	"github.com/anacrolix/torrent/storage"
 )
@@ -48,7 +49,7 @@ func (p badStoragePiece) MarkNotComplete() error {
 }
 
 func (p badStoragePiece) randomlyTruncatedDataString() string {
-	return "hello, world\n"[:rand.Intn(14)]
+	return testutil.GreetingFileContents[:rand.Intn(14)]
 }
 
 func (p badStoragePiece) ReadAt(b []byte, off int64) (n int, err error) {

client_test.go

@@ -9,9 +9,11 @@ import (
 	"path/filepath"
 	"reflect"
 	"testing"
+	"testing/iotest"
 	"time"
 
 	"github.com/bradfitz/iter"
+	"github.com/frankban/quicktest"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 
@@ -202,9 +204,7 @@ func TestCompletedPieceWrongSize(t *testing.T) {
 	assert.True(t, new)
 	r := tt.NewReader()
 	defer r.Close()
-	b, err = ioutil.ReadAll(r)
+	quicktest.Check(t, iotest.TestReader(r, []byte(testutil.GreetingFileContents)), quicktest.IsNil)
-	assert.Len(t, b, 13)
-	assert.NoError(t, err)
 }
 
 func BenchmarkAddLargeTorrent(b *testing.B) {
@@ -411,9 +411,7 @@ func testAddTorrentPriorPieceCompletion(t *testing.T, alreadyCompleted bool, csf
 	assert.Equal(t, alreadyCompleted, psrs[0].Complete)
 	if alreadyCompleted {
 		r := tt.NewReader()
-		b, err := ioutil.ReadAll(r)
+		quicktest.Check(t, iotest.TestReader(r, []byte(testutil.GreetingFileContents)), quicktest.IsNil)
-		assert.NoError(t, err)
-		assert.EqualValues(t, testutil.GreetingFileContents, b)
 	}
 }
 

reader.go

@@ -144,7 +144,7 @@ func (r *reader) ReadContext(ctx context.Context, b []byte) (n int, err error) {
 	defer r.opMu.Unlock()
 	n, err = r.readOnceAt(b, r.pos, &ctxErr)
 	if n == 0 {
-		if err == nil {
+		if err == nil && len(b) > 0 {
 			panic("expected error")
 		} else {
 			return
@@ -185,7 +185,7 @@ func (r *reader) waitAvailable(pos, wanted int64, ctxErr *error, wait bool) (ava
 			err = errors.New("downloading disabled and data not already available")
 			return
 		}
-		if !wait {
+		if !wait || wanted == 0 {
 			return
 		}
 		r.waitReadable(pos)

test/issue377_test.go

@@ -3,10 +3,10 @@ package test
 import (
 	"errors"
 	"io"
-	"io/ioutil"
 	"os"
 	"sync"
 	"testing"
+	"testing/iotest"
 
 	"github.com/anacrolix/log"
 	pp "github.com/anacrolix/torrent/peer_protocol"
@@ -86,12 +86,10 @@ func testReceiveChunkStorageFailure(t *testing.T, seederFast bool) {
 			// We don't seem to need to seek, but that's probably just because the storage failure is
 			// happening on the first read.
 			r.Seek(0, io.SeekStart)
-			output, err := ioutil.ReadAll(r)
+			if err := iotest.TestReader(r, []byte(testutil.GreetingFileContents)); err != nil {
-			if err != nil {
 				t.Logf("got error while reading: %v", err)
 				return true
 			}
-			assert.EqualValues(t, testutil.GreetingFileContents, output)
 			return false
 		}() {
 		}

test/transfer_test.go

@@ -8,6 +8,7 @@ import (
 	"path/filepath"
 	"sync"
 	"testing"
+	"testing/iotest"
 	"time"
 
 	"github.com/anacrolix/missinggo/v2/filecache"
@@ -15,6 +16,7 @@ import (
 	"github.com/anacrolix/torrent/internal/testutil"
 	"github.com/anacrolix/torrent/storage"
 	sqliteStorage "github.com/anacrolix/torrent/storage/sqlite"
+	"github.com/frankban/quicktest"
 	"golang.org/x/time/rate"
 
 	"github.com/stretchr/testify/assert"
@@ -39,9 +41,7 @@ func assertReadAllGreeting(t *testing.T, r io.ReadSeeker) {
 	pos, err := r.Seek(0, io.SeekStart)
 	assert.NoError(t, err)
 	assert.EqualValues(t, 0, pos)
-	_greeting, err := ioutil.ReadAll(r)
+	quicktest.Check(t, iotest.TestReader(r, []byte(testutil.GreetingFileContents)), quicktest.IsNil)
-	assert.NoError(t, err)
-	assert.EqualValues(t, testutil.GreetingFileContents, string(_greeting))
 }
 
 // Creates a seeder and a leecher, and ensures the data transfers when a read
@@ -413,9 +413,7 @@ func TestSeedAfterDownloading(t *testing.T) {
 		defer wg.Done()
 		r := llg.NewReader()
 		defer r.Close()
-		b, err := ioutil.ReadAll(r)
+		quicktest.Check(t, iotest.TestReader(r, []byte(testutil.GreetingFileContents)), quicktest.IsNil)
-		require.NoError(t, err)
-		assert.EqualValues(t, testutil.GreetingFileContents, b)
 	}()
 	done := make(chan struct{})
 	defer close(done)

torrent_test.go

@@ -2,6 +2,7 @@ package torrent
 
 import (
 	"fmt"
+	"io"
 	"net"
 	"os"
 	"path/filepath"
@@ -92,7 +93,7 @@ func BenchmarkUpdatePiecePriorities(b *testing.B) {
 	for range iter.N(7) {
 		r := t.NewReader()
 		r.SetReadahead(32 << 20)
-		r.Seek(3500000, 0)
+		r.Seek(3500000, io.SeekStart)
 	}
 	assert.Len(b, t.readers, 7)
 	for i := 0; i < int(t.numPieces()); i += 3 {