message: test(integration): prefer log to print messages
diff: @@ -8,7 +8,6 @@ use ckb_core::script::{Script, ScriptHashType};
  use ckb_core::transaction::{CellInput, CellOutput, OutPoint, Transaction, TransactionBuilder};
  use ckb_core::{capacity_bytes, BlockNumber, Bytes, Capacity};
  use ckb_jsonrpc_types::JsonBytes;
  -use log::info;
  use numext_fixed_hash::H256;
  use std::convert::Into;
  use std::fs;
  @@ -34,8 +33,8 @@ struct ProcessGuard(pub Child);
  impl Drop for ProcessGuard {
  fn drop(&mut self) {
  match self.0.kill() {
  - Err(e) => info!("Could not kill ckb process: {}", e),
  - Ok(_) => info!("Successfully killed ckb process"),
  + Err(e) => log::error!("Could not kill ckb process: {}", e),
  + Ok(_) => log::debug!("Successfully killed ckb process"),
  }
  let _ = self.0.wait();
  }
  @@ -83,7 +82,7 @@ impl Node {
  .spawn()
  .expect("failed to run binary");
  self.guard = Some(ProcessGuard(child_process));
  - info!("Started node with working dir: {}", self.dir);
  + log::info!("Started node with working dir: {}", self.dir);
  loop {
  let result = { self.rpc_client().inner().lock().local_node_info().call() };
  @@ -94,14 +93,14 @@ impl Node {
  } else if let Some(ref mut child) = self.guard {
  match child.0.try_wait() {
  Ok(Some(exit)) => {
  - eprintln!("Error: node crashed, {}", exit);
  + log::error!("Error: node crashed, {}", exit);
  process::exit(exit.code().unwrap());
  }
  Ok(None) => {
  std::thread::sleep(std::time::Duration::from_secs(1));
  }
  Err(error) => {
  - eprintln!("Error: node crashed with reason: {}", error);
  + log::error!("Error: node crashed with reason: {}", error);
  process::exit(255);
  }
  }
  