Fix compatibility with pytest-run-parallel and add free-threaded CI jobs

.github/workflows/ci_workflows.yml

@@ -30,6 +30,9 @@ jobs:
         - windows: py312-test-pytest74
         - linux: py313-test-pytest83
         - linux: py313-test-pytest90
+        - linux: py313-test-parallel
+        - linux: py313t-test
+        - linux: py313t-test-parallel
         - linux: py313-test-devdeps
   publish:
     needs: tests

pytest_arraydiff/plugin.py

@@ -240,12 +240,18 @@ def wrap_array_interceptor(plugin, item):
     # Only intercept array on marked array tests
     if item.get_closest_marker('array_compare') is not None:
 
+        # Guard against wrapping more than once (e.g. when pytest-run-parallel
+        # runs the same item multiple times).
+        if getattr(item.obj, '_arraydiff_wrapped', False):
+            return
+
         # Use the full test name as a key to ensure correct array is being retrieved
         test_name = generate_test_name(item)
 
         def array_interceptor(store, obj):
             def wrapper(*args, **kwargs):
                 store.return_value[test_name] = obj(*args, **kwargs)
+            wrapper._arraydiff_wrapped = True
             return wrapper
 
         item.obj = array_interceptor(plugin, item.obj)
@@ -260,6 +266,10 @@ def __init__(self, config, reference_dir=None, generate_dir=None, default_format
         self.default_format = default_format
         self.return_value = {}
 
+    def pytest_collection_modifyitems(self, items):
+        for item in items:
+            wrap_array_interceptor(self, item)
+
     @pytest.hookimpl(hookwrapper=True)
     def pytest_runtest_call(self, item):
 
@@ -298,8 +308,6 @@ def pytest_runtest_call(self, item):
 
         baseline_remote = reference_dir.startswith('http')
 
-        # Run test and get array object
-        wrap_array_interceptor(self, item)
         yield
         test_name = generate_test_name(item)
         if test_name not in self.return_value:
@@ -372,11 +380,11 @@ def __init__(self, config):
         self.config = config
         self.return_value = {}
 
-    @pytest.hookimpl(hookwrapper=True)
-    def pytest_runtest_call(self, item):
-
-        if item.get_closest_marker('array_compare') is not None:
+    def pytest_collection_modifyitems(self, items):
+        for item in items:
             wrap_array_interceptor(self, item)
 
+    @pytest.hookimpl(hookwrapper=True)
+    def pytest_runtest_call(self, item):
         yield
         return

setup.cfg

@@ -35,11 +35,15 @@ install_requires =
     pytest>=5.0
     numpy
 
-# tables limitation is until 3.9.3 is out as that supports ARM OSX.
+# tables limitation is until 3.9.3 is out as that supports ARM OSX, and
+# tables wheels are not yet available for free-threaded CPython.  Since
+# PEP 508 has no marker for that, tables is split into its own extra and
+# tox only installs it on the non-free-threaded envs.
 [options.extras_require]
 test =
     astropy
     pandas
+test_hdf5 =
     tables;platform_machine!='arm64'
 
 [options.entry_points]

tests/test_pytest_arraydiff.py

@@ -177,3 +177,40 @@ def test_single_reference(self, spam):
 
 def test_nofile():
     pass
+
+
+TEST_PARALLEL = """
+import pytest
+import numpy as np
+from astropy.io import fits
+@pytest.mark.array_compare(file_format='fits')
+def test_parallel():
+    return fits.PrimaryHDU(np.arange(3 * 5).reshape((3, 5)).astype(np.int64))
+"""
+
+
+def test_parallel_iterations():
+    """Regression test: arraydiff should work with pytest-run-parallel."""
+    pytest.importorskip('pytest_run_parallel')
+
+    tmpdir = tempfile.mkdtemp()
+    test_file = os.path.join(tmpdir, 'test.py')
+    with open(test_file, 'w') as f:
+        f.write(TEST_PARALLEL)
+
+    gen_dir = os.path.join(tmpdir, 'reference')
+
+    # Generate the reference file first
+    code = subprocess.call(
+        ['pytest', f'--arraydiff-generate-path={gen_dir}', test_file],
+        timeout=30,
+    )
+    assert code == 0
+
+    # Now run with --arraydiff and multiple iterations
+    code = subprocess.call(
+        ['pytest', '--arraydiff', f'--arraydiff-reference-path={gen_dir}',
+         '--parallel-threads=2', '--iterations=3', test_file],
+        timeout=30,
+    )
+    assert code == 0

tox.ini

@@ -1,12 +1,14 @@
 [tox]
 envlist =
     py{39,310,311,312,313,314}-test{,-pytestoldest,-pytest52,-pytest53,-pytest60,-pytest61,-pytest62,-pytest70,-pytest71,-pytest72,-pytest73,-pytest74,-devdeps}
+    py{313t,314t}-test{,-parallel}
     codestyle
 isolated_build = true
 
 [testenv]
 changedir = .tmp/{envname}
 setenv =
+    py313t,py314t: PYTHON_GIL = 0
     devdeps: PIP_EXTRA_INDEX_URL = https://pypi.anaconda.org/astropy/simple https://pypi.anaconda.org/liberfa/simple https://pypi.anaconda.org/scientific-python-nightly-wheels/simple
 description = run tests
 deps =
@@ -24,13 +26,19 @@ deps =
     pytest80: pytest==8.0.*
     pytest83: pytest==8.3.*
     pytest90: pytest==9.0.*
+    parallel: pytest-run-parallel
     devdeps: git+https://github.com/pytest-dev/pytest#egg=pytest
     devdeps: numpy>=0.0.dev0
     devdeps: pandas>=0.0.dev0
     devdeps: pyerfa>=0.0.dev0
     devdeps: astropy>=0.0.dev0
 extras =
     test
+    # tables (PyTables) is needed for the pandas/HDF5 file_format, but
+    # has no free-threaded wheels and its sdist requires libhdf5-dev,
+    # which CI does not install.  Skip the HDF5 extras on free-threaded
+    # envs.
+    !py313t-!py314t: test_hdf5
 commands =
     # Force numpy-dev after something in the stack downgrades it
     devdeps: python -m pip install --pre --upgrade --extra-index-url https://pypi.anaconda.org/scientific-python-nightly-wheels/simple numpy