Add mrcs extension to ext list for Image.load

src/aspire/image/image.py

@@ -147,6 +147,7 @@ class Image:
     # Map file extensions to their respective readers
     extensions = {
         ".mrc": load_mrc,
+        ".mrcs": load_mrc,
         ".tif": load_tiff,
         ".tiff": load_tiff,
     }

tests/test_image.py

@@ -458,7 +458,7 @@ def test_load_bad_ext():
 
 def test_load_mrc(dtype):
     """
-    Test `Image.load` round-trip.
+    Test `Image.load` round-trip for `mrc` extension.
     """
 
     # `sample.mrc` is single precision
@@ -480,6 +480,30 @@ def test_load_mrc(dtype):
     assert im2.dtype == dtype
 
 
+def test_load_mrcs(dtype):
+    """
+    Test `Image.load` round-trip for `mrcs` extension.
+    """
+
+    # `sample.mrcs` is single precision
+    filepath = os.path.join(DATA_DIR, "sample.mrcs")
+
+    # Load data from file
+    im = Image.load(filepath, dtype=dtype)
+
+    with tempfile.TemporaryDirectory() as tmpdir_name:
+        # tmp filename
+        test_filepath = os.path.join(tmpdir_name, "test.mrcs")
+
+        im.save(test_filepath)
+
+        im2 = Image.load(test_filepath, dtype)
+
+    # Check the single precision round-trip
+    assert np.array_equal(im, im2)
+    assert im2.dtype == dtype
+
+
 def test_load_tiff():
     """
     Test `Image.load` with a TIFF file