message: fix: get_cell_meta should return None if output index is not exists
diff: @@ -249,16 +249,16 @@ pub trait ChainStore<'a>: Send + Sync {
  self.get_transaction_info_packed(&tx_hash)
  .and_then(|tx_info| {
  self.get(COLUMN_BLOCK_BODY, tx_info.key().as_slice())
  - .map(|slice| {
  + .and_then(|slice| {
  let reader =
  packed::TransactionViewReader::from_slice_should_be_ok(&slice.as_ref());
  - let cell_output = reader
  + reader
  .data()
  .raw()
  .outputs()
  .get(index as usize)
  - .expect("inconsistent index")
  - .to_entity();
  + .map(|cell_output| {
  + let cell_output = cell_output.to_entity();
  let data_bytes = reader
  .data()
  .raw()
  @@ -281,6 +281,7 @@ pub trait ChainStore<'a>: Send + Sync {
  }
  })
  })
  + })
  }
  fn get_cell_data(
  