Re: [PATCH 1/3] tests/functional: return output from exec_command_and_wait_for_pattern()

["Daniel P. Berrangé" <berrange@redhat.com>]

On Mon, Aug 18, 2025 at 12:05:44PM +0100, John Levon wrote:
> Tests might want to look at the whole output from a command execution,
> as well as just logging it. Add support for this.
> 
> Signed-off-by: John Levon <john.levon@nutanix.com>
> ---
>  tests/functional/qemu_test/cmd.py | 38 +++++++++++++++++++++++++++----
>  1 file changed, 33 insertions(+), 5 deletions(-)
> 
> diff --git a/tests/functional/qemu_test/cmd.py b/tests/functional/qemu_test/cmd.py
> index dc5f422b77..6355b1a683 100644
> --- a/tests/functional/qemu_test/cmd.py
> +++ b/tests/functional/qemu_test/cmd.py
> @@ -45,6 +45,9 @@ def is_readable_executable_file(path):
>  # If end of line is seen, with neither @success or @failure
>  # return False
>  #
> +# In both cases, also return the contents of the line (in bytes)
> +# up to that point.
> +#
>  # If @failure is seen, then mark @test as failed
>  def _console_read_line_until_match(test, vm, success, failure):
>      msg = bytes([])
> @@ -76,10 +79,23 @@ def _console_read_line_until_match(test, vm, success, failure):
>      except:
>          console_logger.debug(msg)
>  
> -    return done
> +    return done, msg
>  
>  def _console_interaction(test, success_message, failure_message,
>                           send_string, keep_sending=False, vm=None):
> +    """
> +    Interact with the console until either message is seen.
> +
> +    :param success_message: if this message appears, finish interaction
> +    :param failure_message: if this message appears, test fails
> +    :param send_string: a string to send to the console before trying
> +                        to read a new line
> +    :param keep_sending: keep sending the send string each time
> +    :param vm: the VM to interact with
> +
> +    :return: The collected output (in bytes form).
> +    """
> +
>      assert not keep_sending or send_string
>      assert success_message or send_string
>  
> @@ -101,6 +117,8 @@ def _console_interaction(test, success_message, failure_message,
>      if failure_message is not None:
>          failure_message_b = failure_message.encode()
>  
> +    out = bytes([])
> +
>      while True:
>          if send_string:
>              vm.console_socket.sendall(send_string.encode())
> @@ -113,11 +131,17 @@ def _console_interaction(test, success_message, failure_message,
>                  break
>              continue
>  
> -        if _console_read_line_until_match(test, vm,
> -                                          success_message_b,
> -                                          failure_message_b):
> +        done, line = _console_read_line_until_match(test, vm,
> +                                                    success_message_b,
> +                                                    failure_message_b)
> +
> +        out += line
> +
> +        if done:
>              break
>  
> +    return out
> +
>  def interrupt_interactive_console_until_pattern(test, success_message,
>                                                  failure_message=None,
>                                                  interrupt_string='\r'):
> @@ -184,9 +208,13 @@ def exec_command_and_wait_for_pattern(test, command,
>      :param command: the command to send
>      :param success_message: if this message appears, test succeeds
>      :param failure_message: if this message appears, test fails
> +
> +    :return: The collected output (in bytes form).
>      """
>      assert success_message
> -    _console_interaction(test, success_message, failure_message, command + '\r')
> +
> +    return _console_interaction(test, success_message, failure_message,
> +                                command + '\r')

Looks reasonable, but there are a few other methods whjich call
_console_interaction() - can you make them also return the
matched bytes for consistency.


With regards,
Daniel
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