t.Errorf("Read error: got %T, want testError1", err)
	}
	if _, err := rb.TryRead([]byte{0}); err != (testError1{}) {
		t.Errorf("Read error: got %T, want testError1", err)
	}
}

func TestRingBufferCloseErrorUnblocks(t *testing.T) {
	const sz = 100
	rb := New(sz).SetBlocking(true)

	testCancel := func(fn func()) {
		t.Helper()
		defer timeout(5 * time.Second)()
		rb.Reset()
		done := make(chan struct{})