Stop free-threaded CI jobs failing in setup before tests run (#1089)

Three matrix entries were red without ever running pytest: an earlier
setup step aborted under "bash -e", so "run tests" showed as skipped.
Both causes were environment drift, not code.

3.13t (ubuntu + macos): hypothesis has no free-threaded 3.13 wheel and
its source build pulls pyo3-ffi, which reports "PyO3 does not support
the free-threaded build of CPython versions below 3.14". Install it
best-effort. That alone is insufficient -- test_runningstats.py and
test_scalene_json.py import hypothesis at module scope, and a collection
error there interrupts the entire pytest session -- so both now call
pytest.importorskip("hypothesis"), matching the convention already used
for torch and numpy.

3.14t (ubuntu): "apt-get install -y gdb" exited 100 on a 404 for
libc6-dbg, the image's package index being older than the mirror's
contents. Run apt-get update first, and don't let a missing gdb stop the
job -- it only feeds the optional, already-guarded "Collect crash
backtraces" step.

All four free-threaded jobs pass on this PR, up from one.

Author: emeryberger

.github/workflows/tests.yml

@@ -87,7 +87,15 @@ jobs:
 
     - name: install test dependencies
       run: |
-        python3 -m pip install pytest pytest-asyncio hypothesis
+        python3 -m pip install pytest pytest-asyncio
+        # hypothesis ships no wheel for free-threaded CPython 3.13, and
+        # building it from source fails there: its dependency chain pulls
+        # pyo3-ffi, and "PyO3 does not support the free-threaded build of
+        # CPython versions below 3.14". That aborted this step under
+        # ``bash -e``, so the 3.13t jobs never reached ``run tests`` at all.
+        # Install it best-effort; the two modules that need it call
+        # pytest.importorskip("hypothesis") and skip when it's absent.
+        python3 -m pip install hypothesis || echo "hypothesis unavailable; property-based tests will skip"
         # torch/JAX/TensorFlow may not be available on free-threaded Python builds
         python3 -m pip install torch --index-url https://download.pytorch.org/whl/cpu || true
         python3 -m pip install -e ".[test]" || python3 -m pip install -e .
@@ -97,7 +105,14 @@ jobs:
       run: |
         ulimit -c unlimited
         echo '/tmp/core.%e.%p' | sudo tee /proc/sys/kernel/core_pattern
-        sudo apt-get install -y gdb
+        # ``apt-get update`` first: the runner image ships a package index
+        # that can be older than the mirror's contents, and installing gdb
+        # then 404s on a superseded libc6-dbg. That failed the whole step
+        # (exit 100), skipping ``run tests`` on 3.14t. gdb is only used by
+        # the optional "Collect crash backtraces" step, so never let its
+        # absence stop the job.
+        sudo apt-get update || true
+        sudo apt-get install -y gdb || echo "gdb unavailable; crash backtraces will be skipped"
 
     - name: Quick memory profiling smoke test
       if: runner.os == 'Linux' && endsWith(matrix.python, 't')

tests/test_runningstats.py

@@ -1,11 +1,19 @@
 from scalene import runningstats
 
-import hypothesis.strategies as st
 import math
+import pytest
 
-from hypothesis import given
 from typing import List
 
+# hypothesis has no wheel for free-threaded CPython 3.13 and its source
+# build fails there (PyO3 doesn't support free-threaded < 3.14), so CI
+# installs it best-effort. Skip rather than error out collection.
+pytest.importorskip("hypothesis")
+
+import hypothesis.strategies as st  # noqa: E402
+
+from hypothesis import given  # noqa: E402
+
 TOLERANCE = 0.5
 
 

tests/test_scalene_json.py

@@ -1,10 +1,16 @@
 from scalene import scalene_json
 
-from hypothesis import given
-from hypothesis.strategies import floats, lists
+import pytest
 
 from typing import Any, List
 
+# See tests/test_runningstats.py: hypothesis is installed best-effort in CI
+# because it can't be built for free-threaded CPython 3.13.
+pytest.importorskip("hypothesis")
+
+from hypothesis import given  # noqa: E402
+from hypothesis.strategies import floats, lists  # noqa: E402
+
 
 class TestScaleneJSON:
     # Define strategies for the input variables