Try disabling xdist for 3.8 to pass!?

Author: hynek

pyproject.toml

@@ -51,7 +51,6 @@ tests = [
   "pympler",
   # 4.3.0 dropped last use of `convert`
   "pytest>=4.3.0",
-  "pytest-xdist[psutil]",
 ]
 cov = [
   { include-group = "tests" },

tox.ini

@@ -23,7 +23,7 @@ dependency_groups =
     tests: tests
     mypy: tests-mypy
 commands =
-    tests: pytest {posargs:-n auto}
+    tests: pytest {posargs}
     mypy: mypy tests/typing_example.py
     mypy: mypy src/attrs/__init__.pyi src/attr/__init__.pyi src/attr/_typing_compat.pyi src/attr/_version_info.pyi src/attr/converters.pyi src/attr/exceptions.pyi src/attr/filters.pyi src/attr/setters.pyi src/attr/validators.pyi
 
@@ -35,8 +35,7 @@ set_env =
     COVERAGE_PROCESS_START={toxinidir}/pyproject.toml
     PYTHONWARNINGS=d
 commands_pre = python -c 'import pathlib; pathlib.Path("{env_site_packages_dir}/cov.pth").write_text("import coverage; coverage.process_startup()")'
-# We group xdist execution by file because otherwise the Mypy tests have race conditions.
-commands = coverage run -m pytest {posargs:-n auto --dist loadfile}
+commands = coverage run -m pytest {posargs}
 
 [testenv:coverage-report]
 # Keep base_python in-sync with .python-version-default