LangBot/tests/README.md

LangBot Test Suite

This directory contains the test suite for LangBot, with a focus on comprehensive unit testing of pipeline stages.

Important Note

Due to circular import dependencies in the pipeline module structure, the test files use lazy imports via importlib.import_module() instead of direct imports. This ensures tests can run without triggering circular import errors.

Structure

tests/
├── pipeline/                      # Pipeline stage tests
│   ├── conftest.py               # Shared fixtures and test infrastructure
│   ├── test_simple.py            # Basic infrastructure tests (always pass)
│   ├── test_bansess.py           # BanSessionCheckStage tests
│   ├── test_ratelimit.py         # RateLimit stage tests
│   ├── test_preproc.py           # PreProcessor stage tests
│   ├── test_respback.py          # SendResponseBackStage tests
│   ├── test_resprule.py          # GroupRespondRuleCheckStage tests
│   ├── test_pipelinemgr.py       # PipelineManager tests
│   └── test_stages_integration.py # Integration tests
└── README.md                      # This file

Test Architecture

Fixtures (conftest.py)

The test suite uses a centralized fixture system that provides:

• MockApplication: Comprehensive mock of the Application object with all dependencies
• Mock objects: Pre-configured mocks for Session, Conversation, Model, Adapter
• Sample data: Ready-to-use Query objects, message chains, and configurations
• Helper functions: Utilities for creating results and common assertions

Design Principles

1. Isolation: Each test is independent and doesn't rely on external systems
2. Mocking: All external dependencies are mocked to ensure fast, reliable tests
3. Coverage: Tests cover happy paths, edge cases, and error conditions
4. Extensibility: Easy to add new tests by reusing existing fixtures

Running Tests

Using the test runner script (recommended)

bash run_tests.sh

This script automatically:

• Activates the virtual environment
• Installs test dependencies if needed
• Runs tests with coverage
• Generates HTML coverage report

Manual test execution

Run all tests

pytest tests/pipeline/

Run only simple tests (no imports, always pass)

pytest tests/pipeline/test_simple.py -v

Run specific test file

pytest tests/pipeline/test_bansess.py -v

Run with coverage

pytest tests/pipeline/ --cov=pkg/pipeline --cov-report=html

Run specific test

pytest tests/pipeline/test_bansess.py::test_bansess_whitelist_allow -v

Known Issues

Some tests may encounter circular import errors. This is a known issue with the current module structure. The test infrastructure is designed to work around this using lazy imports, but if you encounter issues:

1. Make sure you're running from the project root directory
2. Ensure the virtual environment is activated
3. Try running test_simple.py first to verify the test infrastructure works

CI/CD Integration

Tests are automatically run on:

• Pull request opened
• Pull request marked ready for review
• Push to PR branch
• Push to master/develop branches

The workflow runs tests on Python 3.10, 3.11, and 3.12 to ensure compatibility.

Adding New Tests

1. For a new pipeline stage

Create a new test file test_<stage_name>.py:

"""
<StageName> stage unit tests
"""

import pytest
from pkg.pipeline.<module>.<stage> import <StageClass>
from pkg.pipeline import entities as pipeline_entities


@pytest.mark.asyncio
async def test_stage_basic_flow(mock_app, sample_query):
    """Test basic flow"""
    stage = <StageClass>(mock_app)
    await stage.initialize({})

    result = await stage.process(sample_query, '<StageName>')

    assert result.result_type == pipeline_entities.ResultType.CONTINUE

2. For additional fixtures

Add new fixtures to conftest.py:

@pytest.fixture
def my_custom_fixture():
    """Description of fixture"""
    return create_test_data()

3. For test data

Use the helper functions in conftest.py:

from tests.pipeline.conftest import create_stage_result, assert_result_continue

result = create_stage_result(
    result_type=pipeline_entities.ResultType.CONTINUE,
    query=sample_query
)

assert_result_continue(result)

Best Practices

1. Test naming: Use descriptive names that explain what's being tested
2. Arrange-Act-Assert: Structure tests clearly with setup, execution, and verification
3. One assertion per test: Focus each test on a single behavior
4. Mock appropriately: Mock external dependencies, not the code under test
5. Use fixtures: Reuse common test data through fixtures
6. Document tests: Add docstrings explaining what each test validates

Troubleshooting

Import errors

Make sure you've installed the package in development mode:

uv pip install -e .

Async test failures

Ensure you're using @pytest.mark.asyncio decorator for async tests.

Mock not working

Check that you're mocking at the right level and using AsyncMock for async functions.

Future Enhancements

• Add integration tests for full pipeline execution
• Add performance benchmarks
• Add mutation testing for better coverage quality
• Add property-based testing with Hypothesis