tests: add missing fixtures for S3FileSystem

tests/test_rtdc_fmt_s3.py

@@ -10,6 +10,11 @@
 
 from dclab.rtdc_dataset.fmt_s3 import is_s3_url, is_s3_object_available
 
+try:
+    from s3fs import S3FileSystem
+except ImportError:
+    S3FileSystem = None
+
 
 pytest.importorskip("s3fs")
 
@@ -22,6 +27,14 @@
                     allow_module_level=True)
 
 
+@pytest.fixture(autouse=True)
+def s3fs_cleanup():
+    # Clear the cache so we get a clean slate every time we instantiate
+    # an S3FileSystem.
+    yield
+    S3FileSystem.cachable = False
+
+
 def test_cache_features():
     # This is the calibration beads measurement.
     # https://dcor.mpl.mpg.de/dataset/figshare-7771184-v2/
@@ -30,14 +43,14 @@ def test_cache_features():
               "circle-5a7a053d-55fb-4f99-960c-f478d0bd418f/"
               "resource/fb7/19f/b2-bd9f-817a-7d70-f4002af916f0")
 
-    ds = dclab.new_dataset(s3_url)
-    t0 = time.perf_counter()
-    _ = ds["deform"][:]
-    t1 = time.perf_counter()
-    for ii in range(50):
+    with dclab.new_dataset(s3_url) as ds:
+        t0 = time.perf_counter()
         _ = ds["deform"][:]
-    t2 = time.perf_counter()
-    assert t2 - t1 < t1 - t0
+        t1 = time.perf_counter()
+        for ii in range(50):
+            _ = ds["deform"][:]
+        t2 = time.perf_counter()
+        assert t2 - t1 < t1 - t0
 
 
 @pytest.mark.parametrize("url, avail", [
@@ -67,12 +80,12 @@ def test_open_public_s3_dataset():
               "circle-5a7a053d-55fb-4f99-960c-f478d0bd418f/"
               "resource/fb7/19f/b2-bd9f-817a-7d70-f4002af916f0")
 
-    ds = dclab.new_dataset(s3_url)
-    assert ds.config["experiment"]["sample"] == "calibration_beads"
-    assert len(ds) == 5000
-    assert np.allclose(ds["deform"][100], 0.013640802,
-                       atol=0,
-                       rtol=1e-5)
+    with dclab.new_dataset(s3_url) as ds:
+        assert ds.config["experiment"]["sample"] == "calibration_beads"
+        assert len(ds) == 5000
+        assert np.allclose(ds["deform"][100], 0.013640802,
+                           atol=0,
+                           rtol=1e-5)
 
 
 @pytest.mark.parametrize("url", [

tests/test_rtdc_fmt_s3_basin.py

@@ -10,6 +10,11 @@
 from dclab import new_dataset, RTDCWriter
 from dclab.rtdc_dataset.fmt_s3 import S3Basin
 
+try:
+    from s3fs import S3FileSystem
+except ImportError:
+    S3FileSystem = None
+
 
 from helper_methods import retrieve_data
 
@@ -30,6 +35,14 @@
                     allow_module_level=True)
 
 
+@pytest.fixture()
+def s3fs_cleanup():
+    # Clear the cache so we get a clean slate every time we instantiate
+    # an S3FileSystem.
+    yield
+    S3FileSystem.cachable = False
+
+
 def test_basin_as_dict(tmp_path):
     tmp_path = tmp_path.resolve()
     h5path = tmp_path / "test_basin_s3.rtdc"