Updated script that can be controled by Nodejs web app

lib/python3.13/site-packages/trio/_tests/test_scheduler_determinism.py

@@ -0,0 +1,47 @@
+from __future__ import annotations
+
+from typing import TYPE_CHECKING
+
+import trio
+
+if TYPE_CHECKING:
+    import pytest
+
+
+async def scheduler_trace() -> tuple[tuple[str, int], ...]:
+    """Returns a scheduler-dependent value we can use to check determinism."""
+    trace = []
+
+    async def tracer(name: str) -> None:
+        for i in range(50):
+            trace.append((name, i))
+            await trio.lowlevel.checkpoint()
+
+    async with trio.open_nursery() as nursery:
+        for i in range(5):
+            nursery.start_soon(tracer, str(i))
+
+    return tuple(trace)
+
+
+def test_the_trio_scheduler_is_not_deterministic() -> None:
+    # At least, not yet.  See https://github.com/python-trio/trio/issues/32
+    traces = [trio.run(scheduler_trace) for _ in range(10)]
+    assert len(set(traces)) == len(traces)
+
+
+def test_the_trio_scheduler_is_deterministic_if_seeded(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    monkeypatch.setattr(trio._core._run, "_ALLOW_DETERMINISTIC_SCHEDULING", True)
+    traces = []
+    for _ in range(10):
+        state = trio._core._run._r.getstate()
+        try:
+            trio._core._run._r.seed(0)
+            traces.append(trio.run(scheduler_trace))
+        finally:
+            trio._core._run._r.setstate(state)
+
+    assert len(traces) == 10
+    assert len(set(traces)) == 1