Covered Theme module with tests

- Extracted `ColorReplacementGenerator`;
- Extracted `ColorConverterImpl`;
- Added documentation to some classes;
- `hex_to_rgba` now supports shorthand hex colors (#fff).

tests/utils/theme/test_theme_installer.py

@@ -0,0 +1,109 @@
+import os
+import shutil
+import unittest
+from unittest.mock import Mock
+
+from scripts import config
+from scripts.utils.theme.theme_installer import ThemeInstaller
+from scripts.utils.theme.theme_path_provider import ThemePathProvider
+from ..._helpers import create_dummy_file
+
+
+class ThemeInstallerTestCase(unittest.TestCase):
+    def setUp(self):
+        self.theme_type = "gnome-shell"
+        self.source_folder = os.path.join(config.temp_tests_folder, "theme_installer_source")
+        self.destination_folder = os.path.join(config.temp_tests_folder, "theme_installer_destination")
+        self.custom_destination_folder = os.path.join(config.temp_tests_folder, "theme_installer_custom_destination")
+
+        self.logger_factory = Mock()
+        self.color_applier = Mock()
+        self.path_provider = ThemePathProvider()
+        self.path_provider.get_theme_path = Mock(return_value=self.destination_folder)
+
+        self.theme_installer = ThemeInstaller(
+            theme_type=self.theme_type,
+            source_folder=self.source_folder,
+            destination_folder=self.destination_folder,
+            logger_factory=self.logger_factory,
+            color_applier=self.color_applier,
+            path_provider=self.path_provider,
+        )
+
+        self._setup_source_folder()
+
+    def tearDown(self):
+        shutil.rmtree(self.source_folder, ignore_errors=True)
+        shutil.rmtree(self.destination_folder, ignore_errors=True)
+        shutil.rmtree(self.custom_destination_folder, ignore_errors=True)
+
+    def _setup_source_folder(self):
+        os.makedirs(self.source_folder, exist_ok=True)
+        first_file = os.path.join(self.source_folder, "file1.css")
+        second_file = os.path.join(self.source_folder, "file2.css")
+        first_css = "body { background-color: ACCENT-COLOR; color: ACCENT_HOVER; }"
+        second_css = "body { background-color: BACKGROUND-COLOR; }"
+        create_dummy_file(first_file, first_css)
+        create_dummy_file(second_file, second_css)
+
+    def test_install_calls_get_theme_path_and_apply_methods_with_correct_parameters(self):
+        theme_color = Mock()
+        theme_color.modes = ["light"]
+        name = "test-theme"
+
+        self.theme_installer.install(theme_color, name)
+
+        # noinspection PyUnresolvedReferences
+        self.path_provider.get_theme_path.assert_called_once_with(
+            self.destination_folder, name, "light", self.theme_type
+        )
+        self.color_applier.apply.assert_called_once_with(theme_color, self.destination_folder, "light")
+
+    def test_install_with_custom_destination_calls_get_theme_path_and_apply_methods_with_correct_parameters(self):
+        theme_color = Mock()
+        theme_color.modes = ["light"]
+        name = "test-theme"
+        os.makedirs(self.custom_destination_folder, exist_ok=True)
+
+        self.theme_installer.install(theme_color, name, self.custom_destination_folder)
+
+        # noinspection PyUnresolvedReferences
+        self.path_provider.get_theme_path.assert_not_called()
+        self.color_applier.apply.assert_called_once_with(theme_color, self.custom_destination_folder, "light")
+
+    def test_install_with_multiple_modes_calls_get_theme_path_and_apply_methods_for_each_mode(self):
+        theme_color = Mock()
+        theme_color.modes = ["light", "dark"]
+        name = "test-theme"
+
+        self.theme_installer.install(theme_color, name)
+
+        # noinspection PyUnresolvedReferences
+        self.assertEqual(self.path_provider.get_theme_path.call_count, 2)
+        self.assertEqual(self.color_applier.apply.call_count, 2)
+
+    def test_install_raises_exception_and_logs_error(self):
+        theme_color = Mock()
+        theme_color.modes = ["light"]
+        name = "test-theme"
+        self.color_applier.apply.side_effect = Exception("Test error")
+
+        with self.assertRaises(Exception):
+            self.theme_installer.install(theme_color, name)
+
+        logger_mock = self.logger_factory.create_logger.return_value
+        self.assertTrue(logger_mock.error.called)
+
+    def test_install_copies_files_to_destination(self):
+        theme_color = Mock()
+        theme_color.modes = ["light"]
+        name = "test-theme"
+        destination = os.path.join(self.destination_folder, "actual_destination")
+        self.path_provider.get_theme_path.return_value = destination
+
+        self.theme_installer.install(theme_color, name)
+
+        first_file_exists = os.path.exists(os.path.join(destination, "file1.css"))
+        second_file_exists = os.path.exists(os.path.join(destination, "file2.css"))
+        self.assertTrue(first_file_exists)
+        self.assertTrue(second_file_exists)