Add mocking-based unit test for the status command (#67)

Also update `pyproject.toml` s.t. it contains settings for the `ruff` formatter and linter that are consistent with the GitHub action.

.github/workflows/pytest.yml

@@ -0,0 +1,29 @@
+name: Unit Tests
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+
+jobs:
+  unit_tests:
+
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        python-version: ["pypy3.9", "pypy3.10", "3.9", "3.10", "3.11", "3.12"]
+    steps:
+      - uses: actions/checkout@v4
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: ${{matrix.python-version}}
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          python -m pip install .
+          pip install pytest pytest-cov
+      - name: Test with pytest
+        run: |
+          pytest -v

pyproject.toml

@@ -35,3 +35,8 @@ package-data = { "qlever" = ["Qleverfiles/*"] }
 
 [tool.pytest.ini_options]
 pythonpath = ["src"]
+
+[tool.ruff]
+line-length = 79 
+[tool.ruff.lint]
+extend-select = ["I"]

test/qlever/commands/test_status_execute.py

@@ -0,0 +1,140 @@
+import sys
+import unittest
+from io import StringIO
+from unittest.mock import MagicMock, call, patch
+
+import qlever.command
+from qlever.commands.status import StatusCommand
+
+
+def get_mock_args(only_show):
+    args = MagicMock()
+    args.cmdline_regex = "^(ServerMain|IndexBuilderMain)"
+    args.show = only_show
+    return [args, args.cmdline_regex, args.show]
+
+
+class TestStatusCommand(unittest.TestCase):
+    @patch("qlever.commands.status.show_process_info")
+    @patch("psutil.process_iter")
+    # testing execute for 2 processes. Just the second one is a qlever process.
+    # Mocking the process_iter and show_process_info method and testing
+    # if the methods are called correctly.
+    def test_execute_processes_found(
+        self, mock_process_iter, mock_show_process_info
+    ):
+        # Mocking the input for the execute function
+        [args, args.cmdline_regex, args.show] = get_mock_args(False)
+
+        # Creating mock psutil.Process objects with necessary attributes
+        mock_process1 = MagicMock()
+        mock_process1.as_dict.return_value = {"test": [1]}
+        # to test with real psutil.process objects use this:
+        """mock_process1.as_dict.return_value = {
+            'cmdline': ['cmdline1'],
+            'pid': 1,
+            'username': 'user1',
+            'create_time': datetime.now().timestamp(),
+            'memory_info': MagicMock(rss=512 * 1024 * 1024)  # 512 MB
+        }"""
+
+        mock_process2 = MagicMock()
+        mock_process2.as_dict.return_value = {"test": [2]}
+        # to test with real psutil.process objects use this:
+        """mock_process2.as_dict.return_value = {
+            'cmdline': ['cmdline2'],
+            'pid': 2,
+            'username': 'user2',
+            'create_time': datetime.now().timestamp(),
+            'memory_info': MagicMock(rss=1024 * 1024 * 1024)  # 1 GB
+        }"""
+
+        mock_process3 = MagicMock()
+        mock_process3.as_dict.return_value = {"test": [3]}
+
+        # Mock the return value of process_iter
+        # to be a list of these mocked process objects
+        mock_process_iter.return_value = [
+            mock_process1,
+            mock_process2,
+            mock_process3,
+        ]
+
+        # Simulate show_process_info returning False for the first
+        # True for the second and False for the third process
+        mock_show_process_info.side_effect = [False, True, False]
+
+        sc = StatusCommand()
+
+        # Execute the function
+        result = sc.execute(args)
+
+        # Assert that process_iter was called once
+        mock_process_iter.assert_called_once()
+
+        # Assert that show_process_info was called 3times
+        # in correct order with the correct arguments
+        expected_calls = [
+            call(mock_process1, args.cmdline_regex, show_heading=True),
+            call(mock_process2, args.cmdline_regex, show_heading=True),
+            call(mock_process3, args.cmdline_regex, show_heading=False),
+        ]
+        mock_show_process_info.assert_has_calls(
+            expected_calls, any_order=False
+        )
+        self.assertTrue(result)
+
+    @patch("qlever.util.show_process_info")
+    @patch("psutil.process_iter")
+    def test_execute_no_processes_found(
+        self, mock_process_iter, mock_show_process_info
+    ):
+        # Mocking the input for the execute function
+        [args, args.cmdline_regex, args.show] = get_mock_args(False)
+
+        # Mock process_iter to return an empty list,
+        # simulating that no matching processes are found
+        mock_process_iter.return_value = []
+
+        # Capture the string-output
+        captured_output = StringIO()
+        sys.stdout = captured_output
+
+        # Instantiate the StatusCommand
+        status_command = StatusCommand()
+
+        # Execute the function
+        result = status_command.execute(args)
+
+        # Reset redirect
+        sys.stdout = sys.__stdout__
+
+        # Assert that process_iter was called once
+        mock_process_iter.assert_called_once()
+
+        # Assert that show_process_info was never called
+        # since there are no processes
+        mock_show_process_info.assert_not_called()
+
+        self.assertTrue(result)
+
+        # Verify the correct output was printed
+        self.assertIn("No processes found", captured_output.getvalue())
+
+    @patch.object(qlever.command.QleverCommand, "show")
+    def test_execute_show_action_description(self, mock_show):
+        # Mocking the input for the execute function
+        [args, args.cmdline_regex, args.show] = get_mock_args(True)
+
+        # Execute the function
+        result = StatusCommand().execute(args)
+
+        # Assert that verifies that show was called with the correct parameters
+        mock_show.assert_any_call(
+            f"Show all processes on this machine where "
+            f"the command line matches {args.cmdline_regex}"
+            f" using Python's psutil library",
+            only_show=args.show,
+        )
+
+        self.assertTrue(result)

test/qlever/commands/test_status_other_methods.py

@@ -0,0 +1,41 @@
+import argparse
+import unittest
+
+from qlever.commands.status import StatusCommand
+
+
+class TestStatusCommand(unittest.TestCase):
+    def test_description(self):
+        result = StatusCommand().description()
+        self.assertEqual(
+            result, "Show QLever processes running on this machine"
+        )
+
+    def test_should_have_qleverfile(self):
+        self.assertFalse(StatusCommand().should_have_qleverfile())
+
+    def test_relevant_qleverfile_arguments(self):
+        result = StatusCommand().relevant_qleverfile_arguments()
+        self.assertEqual(result, {})
+
+    def test_additional_arguments(self):
+        # Create an instance of StatusCommand
+        sc = StatusCommand()
+
+        # Create a parser and a subparser
+        parser = argparse.ArgumentParser()
+        subparser = parser.add_argument_group("test")
+        # Call the method
+        sc.additional_arguments(subparser)
+        # Parse an empty argument list to see the default
+        args = parser.parse_args([])
+
+        # Test that the default value is set correctly
+        self.assertEqual(args.cmdline_regex, "^(ServerMain|IndexBuilderMain)")
+
+        # Test that the help text is correctly set
+        argument_help = subparser._group_actions[-1].help
+        self.assertEqual(
+            argument_help,
+            "Show only processes where the command line matches this regex",
+        )