style: fix pre-commit issues

Author: bendichter

docs/user-guide/storage.rst

@@ -102,8 +102,8 @@ Zarr data (metadata and chunks) to a dictionary.:
 Memory-Mapped Store
 ~~~~~~~~~~~~~~~~~~~~
 
-For performance optimization when working with uncompressed data, you can create a memory-mapped store by subclassing :class:`zarr.storage.LocalStore`. 
-Memory mapping allows direct access to portions of chunk data without loading entire chunks into memory, which can be beneficial when you need to 
+For performance optimization when working with uncompressed data, you can create a memory-mapped store by subclassing :class:`zarr.storage.LocalStore`.
+Memory mapping allows direct access to portions of chunk data without loading entire chunks into memory, which can be beneficial when you need to
 read small slices from large chunks.:
 
    >>> import mmap
@@ -119,7 +119,7 @@ read small slices from large chunks.:
    >>> z = zarr.open_array(store=store)
 
 For example, if you have an array with large 1000x1000 chunks and frequently need to access small 100x100 sections,
-memory mapping can provide efficient access by mapping only the needed portions into memory
+memory mapping can provide efficient access by mapping only the needed portions into memory,
 rather than loading entire chunks.:
 
    >>> # Create an array with large chunks

tests/test_store/test_mmap.py

@@ -1,8 +1,8 @@
 from __future__ import annotations
 
+import mmap
 from typing import TYPE_CHECKING
 
-import mmap
 import pytest
 
 import zarr
@@ -15,7 +15,7 @@
 
 
 class MemoryMappedDirectoryStore(LocalStore):
-    def _fromfile(self, fn):
+    def _fromfile(self, fn: str) -> memoryview:
         with open(fn, "rb") as fh:
             return memoryview(mmap.mmap(fh.fileno(), 0, prot=mmap.PROT_READ))
 
@@ -64,22 +64,20 @@ def test_creates_new_directory(self, tmp_path: pathlib.Path):
     async def test_mmap_slice_reads(self, store: MemoryMappedDirectoryStore) -> None:
         """Test reading slices with memory mapping"""
         # Create array with large chunks
-        z = zarr.create_array(store=store, shape=(2000, 2000), chunks=(1000, 1000), 
-                            dtype='float64')
+        z = zarr.create_array(store=store, shape=(2000, 2000), chunks=(1000, 1000), dtype="float64")
         # Write test data
-        data = zarr.full(shape=(2000, 2000), chunks=(1000, 1000), fill_value=42.0, 
-                        dtype='float64')
+        data = zarr.full(shape=(2000, 2000), chunks=(1000, 1000), fill_value=42.0, dtype="float64")
         z[:] = data[:]
-        
+
         # Test reading various slices
         slices = [
             # Within single chunk
             (slice(100, 200), slice(100, 200)),
             # Across chunk boundaries
             (slice(900, 1100), slice(900, 1100)),
             # Full chunk
-            (slice(0, 1000), slice(0, 1000))
+            (slice(0, 1000), slice(0, 1000)),
         ]
-        
+
         for test_slice in slices:
             assert (z[test_slice] == data[test_slice]).all()