}

		for j, tf := range v.tests {
			switch tf := tf.(type) {
			case testWrite:
				got, err := fw.Write([]byte(tf.str))
				if got != tf.wantCnt || err != tf.wantErr {
					t.Errorf("test %d.%d, Write(%s):\ngot  (%d, %v)\nwant (%d, %v)", i, j, tf.str, got, err, tf.wantCnt, tf.wantErr)
				}
			case testReadFrom:
				f := &testFile{ops: tf.ops}
				got, err := fw.ReadFrom(f)

			return
		}
	} else {
		path := filepath.Join("testdata", zt.Name)
		if zt.Obscured {
			tf, err := obscuretestdata.DecodeToTempFile(path)
			if err != nil {
				t.Errorf("obscuretestdata.DecodeToTempFile(%s): %v", path, err)
				return
			}
			defer os.Remove(tf)
			path = tf
		}
		var rc *ReadCloser
		rc, err = OpenReader(path)
		if err == nil {
			defer rc.Close()
			z = &rc.Reader