sceptre-mcp-server: Instructions file for Kiro

E2E Testing Skill

Activate this skill when writing end-to-end or integration tests for sceptre-mcp-server.

Test Structure

Fixture Pattern

Encapsulate setup in reusable pytest fixtures:

import pytest
from unittest.mock import MagicMock, patch

@pytest.fixture
def sceptre_project(tmp_path):
    config_dir = tmp_path / "config"
    config_dir.mkdir()
    return str(tmp_path)

@pytest.fixture
def mock_plan():
    with patch("sceptre_mcp_server.server.SceptrePlan") as mock:
        plan = MagicMock()
        mock.return_value = plan
        yield plan

Best Practices

• Use pytest fixtures for test setup/teardown
• Use pytest.mark.parametrize for multiple input scenarios
• Test user-observable behavior, not internal implementation
• Keep tests independent — each test starts from a clean state
• Mock Sceptre internals (SceptrePlan, SceptreContext) for unit tests
• Use tmp_path fixture for temporary project directories

What to Test E2E

• Full tool flow: MCP tool call → Sceptre command → formatted response
• Error scenarios: invalid project dir, missing config/, path traversal
• All 22 MCP tools return expected response format
• Diff tool with both deepdiff and difflib modes
• Change set lifecycle: create → describe → list → execute → delete

What NOT to Test E2E

• Sceptre internals (tested by the sceptre project itself)
• AWS API behavior (mock at the Sceptre plan level)
• Every possible CloudFormation error (use parametrize in unit tests)

Debugging Failed Tests

1. Check pytest output with -v and --tb=long
2. Look at mock call args to verify correct API calls
3. Run the specific test in isolation: poetry run pytest -k "test_name" -s
4. Add breakpoint() to stop at a specific point
5. Check fixture teardown for leftover state