scripts: add pytest plugin

Adding pytest plugin dedicated to running pytest tests in Zephyr
project. This plugin provides a dut fixture which allows to handle
bidirectional communication with the device under test. This version
of plugin can be used for tests dedicated to real hardware, QEMU and
native_posix simulator.

Co-authored-by: Lukasz Fundakowski <lukasz.fundakowski@nordicsemi.no>
Co-authored-by: Grzegorz Chwierut <grzegorz.chwierut@nordicsemi.no>
Co-authored-by: Katarzyna Giadla <katarzyna.giadla@nordicsemi.no>
Signed-off-by: Piotr Golyzniak <piotr.golyzniak@nordicsemi.no>

scripts/pylib/pytest-twister-harness/tests/device/qemu_adapter_test.py

@@ -0,0 +1,98 @@
+# Copyright (c) 2023 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: Apache-2.0
+
+import os
+import subprocess
+from typing import Generator
+from unittest import mock
+from unittest.mock import patch
+
+import pytest
+
+from twister_harness.device.qemu_adapter import QemuAdapter
+from twister_harness.exceptions import TwisterHarnessException
+from twister_harness.log_files.log_file import HandlerLogFile, NullLogFile
+from twister_harness.twister_harness_config import DeviceConfig
+
+
+@pytest.fixture(name='device')
+def fixture_device_adapter(tmp_path) -> Generator[QemuAdapter, None, None]:
+    build_dir = tmp_path / 'build_dir'
+    adapter = QemuAdapter(DeviceConfig(build_dir=build_dir))
+    yield adapter
+    try:
+        adapter.stop()  # to make sure all running processes are closed
+    except TwisterHarnessException:
+        pass
+
+
+@patch('shutil.which', return_value='/usr/bin/west')
+def test_if_generate_command_creates_proper_command(patched_which):
+    adapter = QemuAdapter(DeviceConfig(build_dir='build_dir'))
+    adapter.generate_command()
+    assert adapter.command == ['/usr/bin/west', 'build', '-d', 'build_dir', '-t', 'run']
+
+
+@patch('shutil.which', return_value=None)
+def test_if_generate_command_creates_empty_listy_if_west_is_not_installed(patched_which):
+    adapter = QemuAdapter(DeviceConfig())
+    adapter.generate_command()
+    assert adapter.command == []
+
+
+def test_if_qemu_adapter_raises_exception_for_empty_command(device) -> None:
+    device.command = []
+    exception_msg = 'Run simulation command is empty, please verify if it was generated properly.'
+    with pytest.raises(TwisterHarnessException, match=exception_msg):
+        device.flash_and_run(timeout=0.1)
+
+
+def test_if_qemu_adapter_raises_exception_file_not_found(device) -> None:
+    device.command = ['dummy']
+    with pytest.raises(TwisterHarnessException, match='File not found: dummy'):
+        device.flash_and_run(timeout=0.1)
+        device.stop()
+    assert device._exc is not None
+    assert isinstance(device._exc, TwisterHarnessException)
+
+
+@mock.patch('subprocess.Popen', side_effect=subprocess.SubprocessError(1, 'Exception message'))
+def test_if_qemu_adapter_raises_exception_when_subprocess_raised_an_error(patched_run, device):
+    device.command = ['echo', 'TEST']
+    with pytest.raises(TwisterHarnessException, match='Exception message'):
+        device.flash_and_run(timeout=0.1)
+        device.stop()
+
+
+def test_if_qemu_adapter_runs_without_errors(resources, tmp_path) -> None:
+    fifo_file_path = str(tmp_path / 'qemu-fifo')
+    script_path = resources.joinpath('fifo_mock.py')
+    device = QemuAdapter(DeviceConfig(build_dir=str(tmp_path)))
+    device.booting_timeout_in_ms = 1000
+    device.command = ['python', str(script_path), fifo_file_path]
+    device.connect()
+    device.initialize_log_files()
+    device.flash_and_run(timeout=1)
+    lines = list(device.iter_stdout)
+    assert 'Readability counts.' in lines
+    assert os.path.isfile(device.handler_log_file.filename)
+    with open(device.handler_log_file.filename, 'r') as file:
+        file_lines = [line.strip() for line in file.readlines()]
+    assert file_lines[-2:] == lines[-2:]
+    device.disconnect()
+
+
+def test_if_qemu_adapter_finishes_after_timeout(device) -> None:
+    device.command = ['sleep', '0.3']
+    device.flash_and_run(timeout=0.1)
+    device.stop()
+    assert device._process_ended_with_timeout is True
+
+
+def test_handler_and_device_log_correct_initialized_on_qemu(device, tmp_path) -> None:
+    device.device_config.build_dir = tmp_path
+    device.initialize_log_files()
+    assert isinstance(device.handler_log_file, HandlerLogFile)
+    assert isinstance(device.device_log_file, NullLogFile)
+    assert device.handler_log_file.filename.endswith('handler.log')  # type: ignore[union-attr]