Work around nagiosplugin issue about stdout in tests

We basically apply the change from
https://github.com/mpounsett/nagiosplugin/issues/24 as a fixture, but
only when nagiosplugin's version is old.

CHANGELOG.md

@@ -12,6 +12,8 @@
   by @dlax).
 * Work around old pytest versions in type annotations in the test suite.
 * Declare compatibility with click version 7.1 (or higher).
+* In tests, work around nagiosplugin 1.3.2 not properly handling stdout
+  redirection.
 
 ## check_patroni 1.0.0 - 2023-08-28
 

tests/conftest.py

@@ -1,7 +1,9 @@
+import logging
 import sys
 from pathlib import Path
 from threading import Thread
 from typing import Any, Iterator, Tuple
+from unittest.mock import patch
 
 if sys.version_info >= (3, 8):
     from importlib.metadata import version as metadata_version
@@ -13,6 +15,8 @@ from click.testing import CliRunner
 
 from . import PatroniAPI
 
+logger = logging.getLogger(__name__)
+
 
 def numversion(pkgname: str) -> Tuple[int, ...]:
     version = metadata_version(pkgname)
@@ -25,6 +29,19 @@ else:
     from _pytest.tmpdir import TempPathFactory
 
 
+@pytest.fixture(scope="session", autouse=True)
+def nagioplugin_runtime_stdout() -> Iterator[None]:
+    # work around https://github.com/mpounsett/nagiosplugin/issues/24 when
+    # nagiosplugin is older than 1.3.3
+    if numversion("nagiosplugin") < (1, 3, 3):
+        target = "nagiosplugin.runtime.Runtime.stdout"
+        with patch(target, None):
+            logger.warning("patching %r", target)
+            yield None
+    else:
+        yield None
+
+
 @pytest.fixture(
     params=[False, True],
     ids=lambda v: "new-replica-state" if v else "old-replica-state",