Pytest transition

test/python/conftest.py

@@ -1,3 +1,119 @@
+import cantera
+import os
+import sys
+from pathlib import Path
 import pytest
+import tempfile
+
+try:
+    from ruamel import yaml
+except ImportError:
+    import ruamel_yaml as yaml
 
 pytest.register_assert_rewrite("pint.testing")
+
+TEST_DATA_PATH = Path(__file__).parents[1] / "data"
+CANTERA_DATA_PATH = Path(cantera.__file__).parent / "data"
+
+
+def pytest_addoption(parser):
+    parser.addoption(
+        "--save-reference", action="store", default=None,
+        help="Save the reference output files for specific tests. "
+             "Options: diffusion, counterflow_premixed, counterflow_premixed_nonideal, "
+             "combustor, wall"
+    )
+
+def pytest_configure(config):
+    config.addinivalue_line("markers", "slow_test: mark test as slow")
+
+def pytest_collection_modifyitems(config, items):
+    if os.environ.get("CT_SKIP_SLOW", "0") == "1":
+        skip_slow = pytest.mark.skip(reason="slow test")
+        for item in items:
+            if "slow_test" in item.keywords:
+                item.add_marker(skip_slow)
+
+@pytest.fixture
+def allow_deprecated():
+    cantera.suppress_deprecation_warnings()
+    yield
+    cantera.make_deprecation_warnings_fatal()
+
+
+@pytest.fixture
+def has_temperature_derivative_warnings():
+    with pytest.warns(UserWarning, match="ddTScaledFromStruct"):
+        # test warning raised for BlowersMasel and TwoTempPlasma derivatives
+        yield
+
+@pytest.fixture(scope="session")
+def test_data_path():
+    return TEST_DATA_PATH
+
+@pytest.fixture(scope="session")
+def cantera_data_path():
+    return CANTERA_DATA_PATH
+
+@pytest.fixture(scope="module", autouse=True)
+def cantera_setup():
+    """
+    Fixture to set up Cantera environment for the entire test session.
+    """
+    # Add data directories
+    cantera.add_directory(TEST_DATA_PATH)
+    cantera.add_directory(CANTERA_DATA_PATH)
+    cantera.print_stack_trace_on_segfault()
+    cantera.CanteraError.set_stack_trace_depth(20)
+    cantera.make_deprecation_warnings_fatal()
+
+    # Yield control to tests
+    yield
+
+
+@pytest.fixture(scope="class", autouse=True)
+def test_work_path(request, cantera_setup):
+    """
+    Fixture to create a working directory for a test class.
+    This will only run for class-based tests.
+
+    The check on the request.cls attribute is to ensure that this fixture
+    does not run for function-based tests. There is likely a better way to
+    do this, perhaps by disabling autouse and using the fixture explicitly
+    in the test classes that need it.
+    """
+
+    if request.cls is None:
+        # If this is not a class-based test, do nothing.
+        yield
+        return
+
+    root_dir = Path(__file__).parents[2].resolve()
+    if (root_dir / "SConstruct").is_file():
+        work_path = root_dir / "test" / "work" / "python"
+        using_tempfile = False
+        try:
+            work_path.mkdir(exist_ok=True)
+        except FileNotFoundError:
+            work_path = Path(tempfile.mkdtemp())
+            using_tempfile = True
+    else:
+        work_path = Path(tempfile.mkdtemp())
+        using_tempfile = True
+
+    cantera.add_directory(work_path)
+
+    # Assign to the test class
+    request.cls.test_work_path = work_path
+    request.cls.using_tempfile = using_tempfile
+
+    yield
+
+    # Teardown: Remove the working directory if it was a temporary one
+    if using_tempfile:
+        try:
+            for f in work_path.glob("*.*"):
+                f.unlink()
+            work_path.rmdir()
+        except FileNotFoundError:
+            pass

test/python/pytest.ini

@@ -1,2 +1,5 @@
 [pytest]
+markers =
+    slow_test: mark test as slow
+
 pythonpath = ../../build/python