fix: update test to bind mount $HOME in read-only mode

Author: oesteban

.circleci/config.yml

@@ -226,6 +226,7 @@ jobs:
           no_output_timeout: 2h
           command: |
             docker run -ti --rm=false \
+              -e TEST_READONLY_FILESYSTEM=1 -v $HOME:/home/fmriprep:ro \
               --entrypoint="pytest" poldracklab/fmriprep:latest \
               /src/fmriprep/fmriprep -svx --doctest-modules
 

fmriprep/cli/tests/test_version.py

@@ -1,4 +1,5 @@
 """Test version checks."""
+from os import getenv
 from datetime import datetime
 from pathlib import Path
 from packaging.version import Version
@@ -165,9 +166,12 @@ def mock_get(*args, **kwargs):
 
 def test_readonly(tmp_path, monkeypatch):
     """Test behavior when $HOME/.cache/fmriprep/latest can't be written out."""
-    monkeypatch.setenv('HOME', str(tmp_path))
-    cachedir = tmp_path / '.cache'
-    cachedir.mkdir(mode=0o555, exist_ok=True)
+    if getenv('TEST_READONLY_FILESYSTEM'):
+        cachedir = Path(getenv('HOME')) / '.cache'
+    else:
+        monkeypatch.setenv('HOME', str(tmp_path))
+        cachedir = tmp_path / '.cache'
+        cachedir.mkdir(mode=0o555, exist_ok=True)
 
     # Make sure creating the folder will raise the exception.
     with pytest.raises(OSError):