fix xdist

pyproject.toml

@@ -100,7 +100,7 @@ cmake.source-dir = "src/faebryk/core/cpp"
 [tool.pytest]
 [tool.pytest.ini_options]
 # loadscope to run tests for each file in same worker
-addopts = ["--import-mode=importlib", "--numprocesses=auto", "--dist=loadscope"]
+addopts = ["--import-mode=importlib", "--numprocesses=auto"]
 filterwarnings = ["ignore:.*:DeprecationWarning"]
 testpaths = ["test"]
 

src/faebryk/core/cpp/__init__.py

@@ -5,7 +5,7 @@
 import logging
 from importlib.metadata import Distribution
 
-from faebryk.libs.util import ConfigFlag, at_exit
+from faebryk.libs.util import ConfigFlag, at_exit, global_lock
 
 logger = logging.getLogger(__name__)
 
@@ -63,29 +63,30 @@ def compile_and_load():
         if arch in ["arm64", "x86_64"]:
             other_flags += [f"-DCMAKE_OSX_ARCHITECTURES={arch}"]
 
-    run_live(
-        [
-            "cmake",
-            "-S",
-            str(_cmake_dir),
-            "-B",
-            str(_build_dir),
-            "-DEDITABLE=1",
-            "-DPython_EXECUTABLE=" + sys.executable,
-            *other_flags,
-        ],
-        logger=logger,
-    )
-    run_live(
-        [
-            "cmake",
-            "--build",
-            str(_build_dir),
-            "--",
-            "-j",
-        ],
-        logger=logger,
-    )
+    with global_lock(_build_dir / "lock", timeout_s=60):
+        run_live(
+            [
+                "cmake",
+                "-S",
+                str(_cmake_dir),
+                "-B",
+                str(_build_dir),
+                "-DEDITABLE=1",
+                "-DPython_EXECUTABLE=" + sys.executable,
+                *other_flags,
+            ],
+            logger=logger,
+        )
+        run_live(
+            [
+                "cmake",
+                "--build",
+                str(_build_dir),
+                "--",
+                "-j",
+            ],
+            logger=logger,
+        )
 
     if not _build_dir.exists():
         raise RuntimeError("build directory not found")

src/faebryk/libs/util.py

@@ -9,12 +9,14 @@
 import select
 import subprocess
 import sys
+import time
 from abc import abstractmethod
 from collections import defaultdict
 from contextlib import contextmanager
 from dataclasses import dataclass, fields
 from enum import StrEnum
 from itertools import chain
+from pathlib import Path
 from textwrap import indent
 from typing import (
     Any,
@@ -33,6 +35,7 @@
     get_origin,
 )
 
+import psutil
 from tortoise import Model
 from tortoise.queryset import QuerySet
 
@@ -1174,3 +1177,37 @@ def run_live(
         )
 
     return "\n".join(stdout), process
+
+
+@contextmanager
+def global_lock(lock_file_path: Path, timeout_s: float | None = None):
+    # TODO consider using filelock instead
+
+    lock_file_path.parent.mkdir(parents=True, exist_ok=True)
+
+    start_time = time.time()
+    while try_or(
+        lambda: bool(lock_file_path.touch(exist_ok=False)),
+        default=True,
+        catch=FileExistsError,
+    ):
+        # check if pid still alive
+        try:
+            pid = int(lock_file_path.read_text())
+        except ValueError:
+            lock_file_path.unlink()
+            continue
+        assert pid != os.getpid()
+        if not psutil.pid_exists(pid):
+            lock_file_path.unlink()
+            continue
+        if timeout_s and time.time() - start_time > timeout_s:
+            raise TimeoutError()
+        time.sleep(0.1)
+
+    # write our pid to the lock file
+    lock_file_path.write_text(str(os.getpid()))
+    try:
+        yield
+    finally:
+        lock_file_path.unlink()