fix: switch constructor args to match storage.New*, make roots plural

v2/storage/deferred/deferredcarwriter.go

@@ -41,7 +41,7 @@ var _ io.Closer = (*DeferredCarWriter)(nil)
 // HTTP headers in the assumption that the beginning of a valid CAR is about to
 // be streamed.
 type DeferredCarWriter struct {
-	root      cid.Cid
+	roots     []cid.Cid
 	outPath   string
 	outStream io.Writer
 
@@ -58,8 +58,8 @@ type DeferredCarWriter struct {
 //
 // No options are supplied to carstorage.NewWritable by default, add
 // the car.WriteAsCarV1(true) option to write a CARv1 file.
-func NewDeferredCarWriterForPath(root cid.Cid, outPath string, opts ...carv2.Option) *DeferredCarWriter {
-	return &DeferredCarWriter{root: root, outPath: outPath, opts: opts}
+func NewDeferredCarWriterForPath(outPath string, roots []cid.Cid, opts ...carv2.Option) *DeferredCarWriter {
+	return &DeferredCarWriter{roots: roots, outPath: outPath, opts: opts}
 }
 
 // NewDeferredCarWriterForStream creates a DeferredCarWriter that will write to
@@ -69,9 +69,9 @@ func NewDeferredCarWriterForPath(root cid.Cid, outPath string, opts ...carv2.Opt
 // The car.WriteAsCarV1(true) option will be supplied by default to
 // carstorage.NewWritable as CARv2 is not a valid streaming format due to the
 // header.
-func NewDeferredCarWriterForStream(root cid.Cid, outStream io.Writer, opts ...carv2.Option) *DeferredCarWriter {
+func NewDeferredCarWriterForStream(outStream io.Writer, roots []cid.Cid, opts ...carv2.Option) *DeferredCarWriter {
 	opts = append([]carv2.Option{carv2.WriteAsCarV1(true)}, opts...)
-	return &DeferredCarWriter{root: root, outStream: outStream, opts: opts}
+	return &DeferredCarWriter{roots: roots, outStream: outStream, opts: opts}
 }
 
 // OnPut will call a callback when each Put() operation is started. The argument
@@ -140,7 +140,7 @@ func (dcw *DeferredCarWriter) writer() (carstorage.WritableCar, error) {
 			dcw.f = openedFile
 			outStream = openedFile
 		}
-		w, err := carstorage.NewWritable(outStream, []cid.Cid{dcw.root}, dcw.opts...)
+		w, err := carstorage.NewWritable(outStream, dcw.roots, dcw.opts...)
 		if err != nil {
 			return nil, err
 		}

v2/storage/deferred/deferredcarwriter_test.go

@@ -35,7 +35,7 @@ func TestDeferredCarWriterForPath(t *testing.T) {
 			if version == 1 {
 				opts = append(opts, carv2.WriteAsCarV1(true))
 			}
-			cw := deferred.NewDeferredCarWriterForPath(testCid1, tmpFile, opts...)
+			cw := deferred.NewDeferredCarWriterForPath(tmpFile, []cid.Cid{testCid1}, opts...)
 
 			_, err := os.Stat(tmpFile)
 			req.True(os.IsNotExist(err))
@@ -94,11 +94,11 @@ func TestDeferredCarWriter(t *testing.T) {
 			tmpFile := t.TempDir() + "/test.car"
 
 			if tc == "path" {
-				cw = deferred.NewDeferredCarWriterForPath(testCid1, tmpFile, carv2.WriteAsCarV1(true))
+				cw = deferred.NewDeferredCarWriterForPath(tmpFile, []cid.Cid{testCid1}, carv2.WriteAsCarV1(true))
 				_, err := os.Stat(tmpFile)
 				require.True(t, os.IsNotExist(err))
 			} else {
-				cw = deferred.NewDeferredCarWriterForStream(testCid1, &buf)
+				cw = deferred.NewDeferredCarWriterForStream(&buf, []cid.Cid{testCid1})
 				require.Equal(t, buf.Len(), 0)
 			}
 
@@ -169,7 +169,7 @@ func TestDeferredCarWriterPutCb(t *testing.T) {
 	testCid2, testData2 := randBlock()
 
 	var buf bytes.Buffer
-	cw := deferred.NewDeferredCarWriterForStream(testCid1, &buf)
+	cw := deferred.NewDeferredCarWriterForStream(&buf, []cid.Cid{testCid1})
 
 	var pc1 int
 	cw.OnPut(func(ii int) {