pytest plugin for testing CAD/BIM API code inside live host applications via the RevitDevTool Named Pipe bridge.

Write tests locally with pytest; execution happens inside the host process. Currently supported: Revit and AutoCAD family only. Navisworks, Rhino, Tekla, and other hosts are in progress.

pip install revitdevtool_pytest
# or
uv add revitdevtool_pytest

The plugin registry may list additional names for future work. Treat them as experimental until documented here as Supported today.

The plugin connects to the pytest/control pipe:

DevTools_{Host}_{Version}_{PID}

Examples: DevTools_Revit_2025_12345, DevTools_AutoCad_2026_7890

MCP clients use a separate pipe: DevToolsMcp_{Host}_{Version}_{PID}. Do not point pytest at an MCP pipe.

uv init my-host-tests && cd my-host-tests
uv add revitdevtool_pytest pytest

pyproject.toml:

[tool.pytest.ini_options]
host_name = "revit"
host_version = "2025"
force_launch = false
per_test_timeout = "60"
launch_timeout = "180"

tests/conftest.py:

import pytest

@pytest.fixture(scope="session")
def revit_uiapp():
    return __revit__

@pytest.fixture(scope="session")
def revit_doc(revit_uiapp):
    return revit_uiapp.ActiveUIDocument.Document

tests/test_smoke.py:

def test_active_view(revit_doc):
    assert revit_doc.ActiveView is not None

uv run pytest -v

CLI flags override INI: --host, --host-version, --force-launch, --per-test-timeout, --launch-timeout, --host-pipe.

1. force_launch = false (default): scan for DevTools_* pipes matching host_name / host_version, reuse a free instance (suite leasing), or reconnect to a leased PID.
2. No matching instance: auto-launch host when host_version is set (unless --host-pipe pins an existing pipe).
3. force_launch = true: always spawn a new process and wait for its pipe.

Captured print() from in-host tests is shown for passing tests (same as -rP). No extra flags needed.

• Put host API imports inside functions — collection runs on your machine, execution in the host.
• Use fixtures for __revit__, documents, and rollback helpers.
• Declare suite dependencies with PEP 723 in CPython conftest.py (or test_*.py); RevitDevTool installs them before tests/run. IronPython test_*_ipy.py does not use PEP 723 — ipytests/run never installs packages.

# /// script
# dependencies = ["numpy>=2.0", "polars>=1.0"]
# ///

@pytest.fixture
def revit_auto_rollback(revit_transaction_service):
    revit_transaction_service.StartChanges()
    try:
        yield revit_transaction_service
    finally:
        revit_transaction_service.RevertChanges()

1. Local pytest collects tests.
2. Plugin connects to DevTools_{Host}_{Version}_{PID}.
3. Node IDs sent via JSON-RPC method tests/run (BridgeMessage length-prefixed frames).
4. Host runs PytestRunner.py embedded in RevitDevTool (PytestExecutionService on main thread).
5. Results and optional progress notifications return to the client.
6. Plugin maps CaseResult → standard pytest reports.

Clone and run integration tests against a live host:

cd RevitDevTool.PyTest
uv run pytest -v                          # Revit suite (default)
uv run pytest tests/Revit/test_smoke.py -v
uv run pytest --host civil3d --host-version 2026  # after switching testpaths/host in pyproject.toml

Revit suite settings in pyproject.toml: testpaths = ["tests/Revit"], pythonpath = ["tests/Revit"] for local schedule imports.

Optional env: REVIT_TEST_MODEL_PATH — path to .rvt for revit_doc fixture (default F:\Project1.rvt).

VS Code / Cursor — python.testing.pytestEnabled: true. Plugin detects vscode_pytest / TEST_RUN_PIPE and disables CLI streaming to avoid duplicate tree entries.

PyCharm — enable pytest as test runner.

MIT