Write pytests

If you are new to pytest, I recommend you to learn pytest without the complexity of Octoprobe.

Just start with the examples from https://docs.pytest.org/en/stable/how-to/index.html.

You might be interested in

  • fixtures

  • test collection (--collect-only)

  • How to read pytest output (specially the -s flag.)

  • The pytest explorer in VSCode

  • How to debug pytests in VSCode

Setup and Teardown

The hardware has to be prepared for the tests. This is done by pytest before/after entering the tests.

For the example below, two MCU tentacles with PYBv1.1 and Pico are connected and started with this command:

pytest tests/test_simple.py::test_i2c tests/test_simple.py::test_onewire

        sequenceDiagram
   participant pytest
   participant test_i2c as Test I2C
   participant test_onewire as Test onewire
   participant pyb as Tentacle PYBv1.1
   participant pico as Tentacle Pico

   Note over pytest,pico: Setup SESSION

   pytest -) pytest: test collection: Which tentacles/MCU shall be tested?

   pytest -) pytest: git clone micropython, build firmware for required tentacles

   pytest -) pyb: Install firmware, Power off

   pytest -) pico: Install firmware, Power off

   Note over pytest,pico: Test I2C on PYBv1.1

   pytest ->>+ pyb: Function-Setup: Power on
   pytest -) test_i2c: Run test I2C
   test_i2c -) pyb: Download and run I2C micropython code.

   pyb -->>- pytest: Function-Teardown: Power off

   Note over pytest,pico: Test Onewire on PYBv1.1

   pytest ->>+ pyb: Function-Setup: Power on
   pytest -) test_onewire: Run test Onewire
   test_onewire -) pyb: Download and run Onewire micropython code.

   pyb -->>- pytest: Function-Teardown: Power off

   Note over pytest,pico: Test I2C on Pico

   pytest ->>+ pico: Function-Setup: Power on
   pytest -) test_i2c: Run test I2C
   test_i2c -) pico: Download and run I2C micropython code.

   pico -->>- pytest: Function-Teardown: Power off

   Note over pytest,pico: Test Onewire on Pico

   pytest ->>+ pico: Function-Setup: Power on
   pytest -) test_onewire: Run test Onewire
   test_onewire -) pico: Download and run Onewire micropython code.

   pico -->>- pytest: Function-Teardown: Power off

   Note over pytest,pico: Teardown SESSION (does nothing)

Comments to above sequence diagram

  • SESSION setup

    • Will install the firmware and will power off all tentacles.

  • FUNCTION setup:

    • Will power on the required tentacle.

    • Close the relais for the required tentalces.

    • Set the blue LED on.

  • FUNCTION teardown:

    • Will power down the required tentacle.

    • Open the relais for the required tentalces.

    • Set the blue LED off.

References to to source code

  • Sessions setup: pytest fixture

  • Sessions setup: Build the software

  • Session setup: Install the firmware

    CtxTestRun.function_prepare_dut()[source]
    CtxTestRun.function_setup_dut_flash()[source]

  • Function setup: pytest fixture

  • Function setup: Set the relays

    CtxTestRun.setup_relays(tentacles: Sequence[TentacleBase], futs: tuple[StrEnum]) → None[source]

  • The test functions

    tests.test_simple.test_i2c()[source]
    tests.test_simple.test_onewire()[source]