Fix Read Fifo Query RTU Frame Size

[brambo123]

Found a small calculation error in the Read FIFO Query function.
This should fix it, unless a test fails again.

[janiversen]

LGTM, thanks.

Please correct the test harness as we cannot merge a PR without a greenwich CI.

[brambo123]

pymodbus/test/pdu/test_file_message.py

Line 23 in 54d35b4

TEST_MESSAGE = b"\x00\n\x00\x04\x00\x01\x00\x02\x00\x03\x00\x04"

pymodbus/test/pdu/test_file_message.py

Lines 47 to 65 in 54d35b4

	def test_read_fifo_queue_response_encode(self):
	"""Test that the read fifo queue response can encode."""
	message = TEST_MESSAGE
	handle = ReadFifoQueueResponse([1, 2, 3, 4])
	result = handle.encode()
	assert result == message
	def test_read_fifo_queue_response_decode(self):
	"""Test that the read fifo queue response can decode."""
	message = TEST_MESSAGE
	handle = ReadFifoQueueResponse([1, 2, 3, 4])
	handle.decode(message)
	assert handle.values == [1, 2, 3, 4]
	def test_frame_size(self):
	"""Test that the read fifo queue response can decode."""
	message = TEST_MESSAGE
	result = ReadFifoQueueResponse.calculateRtuFrameSize(message)
	assert result == 14

Can someone explain to me what input calculateRtuFrameSize should actually have?
I think it should have the full frame, including the device ID and function code.
But TEST_MESSAGE seems to only be the output of encode(), which I don't think is a full frame?

Edit:
I made a quick change to make it a full frame, and that seems to work.
But I'm not sure if it's correct, and it might not be the most prettiest way to do it.

[janiversen]

I am confused about your question, check the code:

pymodbus/framer/rtu.py line 98.

why would you assume then encode generates what decode wants..it is used in 2 very different situations...but again just look at the code.

[janiversen]

LGTM, Thanks.

[janiversen]

Just saw that the test file have a copy/paste error...all the references to bit/coil/discrete input should clearly have been to file...

This includes the class name.

Feel free to submit a follow up PR if you want to.