fix: throw if both async/sync pytest-playwright plugins are loaded (#282)

Author: mecampbellsoup

.gitignore

@@ -144,3 +144,8 @@ dmypy.json
 
 .DS_Store
 /test-results/
+
+# Claude Code local configuration files
+.claude/
+CLAUDE.local.md
+DEVELOPER.local.md

pytest-playwright-asyncio/pytest_playwright_asyncio/pytest_playwright.py

@@ -282,7 +282,7 @@ async def launch(**kwargs: Dict) -> Browser:
 
 @pytest_asyncio.fixture(scope="session")
 async def browser(
-    launch_browser: Callable[[], Awaitable[Browser]]
+    launch_browser: Callable[[], Awaitable[Browser]],
 ) -> AsyncGenerator[Browser, None]:
     browser = await launch_browser()
     yield browser
@@ -413,7 +413,14 @@ def device(pytestconfig: Any) -> Optional[str]:
     return pytestconfig.getoption("--device")
 
 
-def pytest_addoption(parser: Any) -> None:
+def pytest_addoption(
+    parser: pytest.Parser, pluginmanager: pytest.PytestPluginManager
+) -> None:
+    # Check for incompatible sync plugin early
+    if pluginmanager.has_plugin("pytest_playwright.pytest_playwright"):
+        raise RuntimeError(
+            "pytest-playwright and pytest-playwright-asyncio are not compatible. Please use only one of them."
+        )
     group = parser.getgroup("playwright", "Playwright")
     group.addoption(
         "--browser",

pytest-playwright/pytest_playwright/pytest_playwright.py

@@ -408,7 +408,14 @@ def device(pytestconfig: Any) -> Optional[str]:
     return pytestconfig.getoption("--device")
 
 
-def pytest_addoption(parser: Any) -> None:
+def pytest_addoption(
+    parser: pytest.Parser, pluginmanager: pytest.PytestPluginManager
+) -> None:
+    # Check for incompatible async plugin early
+    if pluginmanager.has_plugin("pytest_playwright_asyncio.pytest_playwright"):
+        raise RuntimeError(
+            "pytest-playwright and pytest-playwright-asyncio are not compatible. Please use only one of them."
+        )
     group = parser.getgroup("playwright", "Playwright")
     group.addoption(
         "--browser",

tests/conftest.py

@@ -15,14 +15,19 @@
 import sys
 import os
 import socket
-from typing import Generator, Optional, Type
+from typing import Any, Generator, Optional, Type
 import pytest
 import threading
 import http.server
 import socketserver
 
 pytest_plugins = ["pytester"]
 
+
+def pytest_configure(config: Any) -> None:
+    config.addinivalue_line("markers", "no_add_ini: mark test to skip adding ini file")
+
+
 # The testdir fixture which we use to perform unit tests will set the home directory
 # To a temporary directory of the created test. This would result that the browsers will
 # be re-downloaded each time. By setting the pw browser path directory we can prevent that.

tests/test_asyncio.py

@@ -32,7 +32,9 @@ def pytester(pytester: pytest.Pytester) -> pytest.Pytester:
 
 
 @pytest.fixture(autouse=True)
-def _add_async_marker(testdir: pytest.Testdir) -> None:
+def _add_ini_asyncio(request: pytest.FixtureRequest, testdir: pytest.Testdir) -> None:
+    if "no_add_ini" in request.keywords:
+        return
     testdir.makefile(
         ".ini",
         pytest="""
@@ -44,6 +46,42 @@ def _add_async_marker(testdir: pytest.Testdir) -> None:
     )
 
 
+@pytest.mark.no_add_ini
+def test_sync_async_incompatibility(testdir: pytest.Testdir) -> None:
+    # This test needs to load both playwright and playwright-asyncio plugins
+    # to trigger the incompatibility check
+    testdir.makefile(
+        ".ini",
+        pytest="""
+        [pytest]
+        addopts = --maxfail=1
+        asyncio_default_test_loop_scope = session
+        asyncio_default_fixture_loop_scope = session
+    """,
+    )
+    testdir.makepyfile(
+        """
+        import pytest
+        @pytest.mark.asyncio
+        async def test_foo():
+            pass
+    """
+    )
+    # Explicitly load both plugins to trigger the incompatibility
+    result = testdir.runpytest(
+        "-p",
+        "pytest_playwright.pytest_playwright",
+        "-p",
+        "pytest_playwright_asyncio.pytest_playwright",
+    )
+    assert result.ret != 0
+    output = "\n".join(result.outlines + result.errlines)
+    assert (
+        "pytest-playwright and pytest-playwright-asyncio are not compatible. Please use only one of them."
+        in output
+    )
+
+
 def test_default(testdir: pytest.Testdir) -> None:
     testdir.makepyfile(
         """
@@ -237,7 +275,7 @@ async def test_is_firefox(page, browser_name, is_chromium, is_firefox, is_webkit
             assert is_chromium is False
             assert is_firefox
             assert is_webkit is False
-    """
+        """
     )
     result = testdir.runpytest("--browser", "firefox")
     result.assert_outcomes(passed=1)

tests/test_sync.py

@@ -33,7 +33,9 @@ def pytester(pytester: pytest.Pytester) -> pytest.Pytester:
 
 
 @pytest.fixture(autouse=True)
-def _add_ini(testdir: pytest.Testdir) -> None:
+def _add_ini(request: pytest.FixtureRequest, testdir: pytest.Testdir) -> None:
+    if "no_add_ini" in request.keywords:
+        return
     testdir.makefile(
         ".ini",
         pytest="""
@@ -43,6 +45,40 @@ def _add_ini(testdir: pytest.Testdir) -> None:
     )
 
 
+@pytest.mark.no_add_ini
+def test_sync_async_incompatibility(testdir: pytest.Testdir) -> None:
+    # This test needs to load both playwright and playwright-asyncio plugins
+    # to trigger the incompatibility check
+    testdir.makefile(
+        ".ini",
+        pytest="""
+        [pytest]
+        addopts = --maxfail=1
+    """,
+    )
+    testdir.makepyfile(
+        """
+        import pytest
+
+        def test_foo():
+            pass
+    """
+    )
+    # Explicitly load both plugins to trigger the incompatibility
+    result = testdir.runpytest(
+        "-p",
+        "pytest_playwright.pytest_playwright",
+        "-p",
+        "pytest_playwright_asyncio.pytest_playwright",
+    )
+    assert result.ret != 0
+    output = "\n".join(result.outlines + result.errlines)
+    assert (
+        "pytest-playwright and pytest-playwright-asyncio are not compatible. Please use only one of them."
+        in output
+    )
+
+
 def test_default(testdir: pytest.Testdir) -> None:
     testdir.makepyfile(
         """