Start adding tests for lower level brightness methods

pytests/helpers.py

@@ -0,0 +1,39 @@
+from abc import ABC, abstractmethod
+from typing import Dict, Optional, Type
+
+from pytest_mock import MockerFixture
+
+from screen_brightness_control.helpers import BrightnessMethod
+
+
+class BrightnessMethodTest(ABC):
+    @abstractmethod
+    def patch(self, mocker: MockerFixture):
+        '''Applies patches to get `get_display_info` working'''
+        ...
+
+    @abstractmethod
+    def method(self) -> Type[BrightnessMethod]:
+        '''Returns the brightness method under test'''
+        ...
+
+    class TestGetDisplayInfo:
+        '''Some standard tests for the `get_display_info` method'''
+        def test_returns_list_of_dict(self, method):
+            info = method.get_display_info()
+            assert isinstance(info, list)
+            assert all(isinstance(i, dict) for i in info)
+
+        def test_returned_dicts_contain_required_keys(self, method, extras: Optional[Dict[str, Type]]=None):
+            info = method.get_display_info()
+            for display in info:
+                for prop in ('name', 'path', 'model', 'serial', 'manufacturer', 'manufacturer_id', 'edid'):
+                    assert prop in display
+                    if display[prop] is not None:
+                        assert isinstance(display[prop], str)
+                assert 'index' in display and isinstance(display['index'], int)
+                assert 'method' in display and display['method'] is method
+                if extras is not None:
+                    for prop, prop_type in extras.items():
+                        assert prop in display
+                        assert isinstance(display[prop], prop_type)

pytests/test_linux.py

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+import os
+from unittest.mock import Mock
+
+import pytest
+from pytest_mock import MockerFixture
+
+import screen_brightness_control as sbc
+from screen_brightness_control.helpers import BrightnessMethod
+
+from .helpers import BrightnessMethodTest
+
+
+class TestSysFiles(BrightnessMethodTest):
+    @pytest.fixture(autouse=True)
+    def patch(self, mocker: MockerFixture):
+        '''Mock everything needed to get `SysFiles.get_display_info` to run'''
+        def listdir(dir: str):
+            if 'subsystem' in dir:
+                return ['intel_backlight', 'acpi_video0']
+            return ['edp1']
+
+        def isfile(file: str):
+            return not file.endswith('device/edid')
+
+        mocker.patch.object(os, 'listdir', Mock(side_effect=listdir))
+        mocker.patch.object(os.path, 'isdir', Mock(return_value=True))
+        mocker.patch.object(os.path, 'isfile', Mock(side_effect=isfile))
+        mocker.patch.object(sbc.linux, 'open', mocker.mock_open(read_data='100'))
+
+    @pytest.fixture
+    def method(self):
+        return sbc.linux.SysFiles
+
+    class TestGetDisplayInfo(BrightnessMethodTest.TestGetDisplayInfo):
+        def test_returned_dicts_contain_required_keys(self, method):
+            super().test_returned_dicts_contain_required_keys(method, extras={'scale': float})