zarr-developers · d-v-b · May 25, 2025 · May 25, 2025 · May 25, 2025 · May 25, 2025
diff --git a/.github/ISSUE_TEMPLATE/bug_report.yml b/.github/ISSUE_TEMPLATE/bug_report.yml
@@ -57,7 +57,22 @@ body:
     id: reproduce
     attributes:
       label: Steps to reproduce
-      description: Minimal, reproducible code sample, a copy-pastable example if possible.
+      description: Minimal, reproducible code sample. Must list dependencies in [inline script metadata](https://packaging.python.org/en/latest/specifications/inline-script-metadata/#example). When put in a file named `issue.py` calling `uv run issue.py` should show the issue.
+      value: |
+        ```python
+        # /// script
+        # requires-python = ">=3.11"
+        # dependencies = [
+        #   "zarr@git+https://github.com/zarr-developers/zarr-python.git@main",
+        # ]
+        # ///
+        #
+        # This script automatically imports the development branch of zarr to check for issues
+
+        import zarr
+        # your reproducer code
+        # zarr.print_debug_info()
+        ```
     validations:
       required: true
   - type: textarea

diff --git a/changes/3081.feature.rst b/changes/3081.feature.rst
@@ -0,0 +1 @@
+Adds ``fill_value`` to the list of attributes displayed in the output of the ``AsyncArray.info()`` method.
diff --git a/docs/user-guide/arrays.rst b/docs/user-guide/arrays.rst
@@ -183,6 +183,7 @@ which can be used to print useful diagnostics, e.g.::
    Type               : Array
    Zarr format        : 3
    Data type          : DataType.int32
+   Fill value         : 0
    Shape              : (10000, 10000)
    Chunk shape        : (1000, 1000)
    Order              : C
@@ -200,6 +201,7 @@ prints additional diagnostics, e.g.::
    Type               : Array
    Zarr format        : 3
    Data type          : DataType.int32
+   Fill value         : 0
    Shape              : (10000, 10000)
    Chunk shape        : (1000, 1000)
    Order              : C
@@ -287,6 +289,7 @@ Here is an example using a delta filter with the Blosc compressor::
    Type               : Array
    Zarr format        : 3
    Data type          : DataType.int32
+   Fill value         : 0
    Shape              : (10000, 10000)
    Chunk shape        : (1000, 1000)
    Order              : C
@@ -601,6 +604,7 @@ Sharded arrays can be created by providing the ``shards`` parameter to :func:`za
   Type               : Array
   Zarr format        : 3
   Data type          : DataType.uint8
+  Fill value         : 0
   Shape              : (10000, 10000)
   Shard shape        : (1000, 1000)
   Chunk shape        : (100, 100)

diff --git a/docs/user-guide/groups.rst b/docs/user-guide/groups.rst
@@ -129,6 +129,7 @@ property. E.g.::
    Type               : Array
    Zarr format        : 3
    Data type          : DataType.int64
+   Fill value         : 0
    Shape              : (1000000,)
    Chunk shape        : (100000,)
    Order              : C
@@ -145,6 +146,7 @@ property. E.g.::
    Type               : Array
    Zarr format        : 3
    Data type          : DataType.float32
+   Fill value         : 0.0
    Shape              : (1000, 1000)
    Chunk shape        : (100, 100)
    Order              : C

diff --git a/docs/user-guide/performance.rst b/docs/user-guide/performance.rst
@@ -92,6 +92,7 @@ To use sharding, you need to specify the ``shards`` parameter when creating the
    Type               : Array
    Zarr format        : 3
    Data type          : DataType.uint8
+   Fill value         : 0
    Shape              : (10000, 10000, 1000)
    Shard shape        : (1000, 1000, 1000)
    Chunk shape        : (100, 100, 100)
@@ -122,6 +123,7 @@ ratios, depending on the correlation structure within the data. E.g.::
    Type               : Array
    Zarr format        : 3
    Data type          : DataType.int32
+   Fill value         : 0
    Shape              : (10000, 10000)
    Chunk shape        : (1000, 1000)
    Order              : C
@@ -141,6 +143,7 @@ ratios, depending on the correlation structure within the data. E.g.::
    Type               : Array
    Zarr format        : 3
    Data type          : DataType.int32
+   Fill value         : 0
    Shape              : (10000, 10000)
    Chunk shape        : (1000, 1000)
    Order              : F

diff --git a/pyproject.toml b/pyproject.toml
@@ -291,8 +291,8 @@ extend-exclude = [
 extend-select = [
     "ANN",  # flake8-annotations
     "B",    # flake8-bugbear
-    "EXE",  # flake8-executable
     "C4",   # flake8-comprehensions
+    "EXE",  # flake8-executable
     "FA",   # flake8-future-annotations
     "FLY",  # flynt
     "FURB", # refurb
@@ -364,14 +364,14 @@ module = [
     "tests.test_store.test_local",
     "tests.test_store.test_fsspec",
     "tests.test_store.test_memory",
+    "tests.test_codecs.test_codecs",
 ]
 strict = false
 
 # TODO: Move the next modules up to the strict = false section
 # and fix the errors
 [[tool.mypy.overrides]]
 module = [
-    "tests.test_codecs.test_codecs",
     "tests.test_metadata.*",
     "tests.test_store.test_core",
     "tests.test_store.test_logging",

diff --git a/src/zarr/api/asynchronous.py b/src/zarr/api/asynchronous.py
@@ -329,7 +329,7 @@ async def open(
         try:
             metadata_dict = await get_array_metadata(store_path, zarr_format=zarr_format)
             # TODO: remove this cast when we fix typing for array metadata dicts
-            _metadata_dict = cast(ArrayMetadataDict, metadata_dict)
+            _metadata_dict = cast("ArrayMetadataDict", metadata_dict)
             # for v2, the above would already have raised an exception if not an array
             zarr_format = _metadata_dict["zarr_format"]
             is_v3_array = zarr_format == 3 and _metadata_dict.get("node_type") == "array"

diff --git a/src/zarr/api/synchronous.py b/src/zarr/api/synchronous.py
@@ -6,7 +6,6 @@
 
 import zarr.api.asynchronous as async_api
 import zarr.core.array
-from zarr._compat import _deprecate_positional_args
 from zarr.core.array import Array, AsyncArray, CompressorLike
 from zarr.core.group import Group
 from zarr.core.sync import sync
@@ -154,7 +153,6 @@ def load(
     )
 
 
-@_deprecate_positional_args
 def open(
     store: StoreLike | None = None,
     *,
@@ -248,7 +246,6 @@ def save(
     )
 
 
-@_deprecate_positional_args
 def save_array(
     store: StoreLike,
     arr: NDArrayLike,
@@ -380,7 +377,6 @@ def array(data: npt.ArrayLike | Array, **kwargs: Any) -> Array:
     return Array(sync(async_api.array(data=data, **kwargs)))
 
 
-@_deprecate_positional_args
 def group(
     store: StoreLike | None = None,
     *,
@@ -448,7 +444,6 @@ def group(
     )
 
 
-@_deprecate_positional_args
 def open_group(
     store: StoreLike | None = None,
     *,

diff --git a/src/zarr/codecs/crc32c_.py b/src/zarr/codecs/crc32c_.py
@@ -40,7 +40,9 @@ async def _decode_single(
         inner_bytes = data[:-4]
 
         # Need to do a manual cast until https://github.com/numpy/numpy/issues/26783 is resolved
-        computed_checksum = np.uint32(crc32c(cast(typing_extensions.Buffer, inner_bytes))).tobytes()
+        computed_checksum = np.uint32(
+            crc32c(cast("typing_extensions.Buffer", inner_bytes))
+        ).tobytes()
         stored_checksum = bytes(crc32_bytes)
         if computed_checksum != stored_checksum:
             raise ValueError(
@@ -55,7 +57,7 @@ async def _encode_single(
     ) -> Buffer | None:
         data = chunk_bytes.as_numpy_array()
         # Calculate the checksum and "cast" it to a numpy array
-        checksum = np.array([crc32c(cast(typing_extensions.Buffer, data))], dtype=np.uint32)
+        checksum = np.array([crc32c(cast("typing_extensions.Buffer", data))], dtype=np.uint32)
         # Append the checksum (as bytes) to the data
         return chunk_spec.prototype.buffer.from_array_like(np.append(data, checksum.view("B")))
 

diff --git a/src/zarr/codecs/sharding.py b/src/zarr/codecs/sharding.py
@@ -115,7 +115,7 @@ class _ShardIndex(NamedTuple):
     def chunks_per_shard(self) -> ChunkCoords:
         result = tuple(self.offsets_and_lengths.shape[0:-1])
         # The cast is required until https://github.com/numpy/numpy/pull/27211 is merged
-        return cast(ChunkCoords, result)
+        return cast("ChunkCoords", result)
 
     def _localize_chunk(self, chunk_coords: ChunkCoords) -> ChunkCoords:
         return tuple(

diff --git a/src/zarr/codecs/transpose.py b/src/zarr/codecs/transpose.py
@@ -23,7 +23,7 @@ def parse_transpose_order(data: JSON | Iterable[int]) -> tuple[int, ...]:
         raise TypeError(f"Expected an iterable. Got {data} instead.")
     if not all(isinstance(a, int) for a in data):
         raise TypeError(f"Expected an iterable of integers. Got {data} instead.")
-    return tuple(cast(Iterable[int], data))
+    return tuple(cast("Iterable[int]", data))
 
 
 @dataclass(frozen=True)

diff --git a/src/zarr/core/_info.py b/src/zarr/core/_info.py
@@ -67,7 +67,7 @@ def byte_info(size: int) -> str:
         return f"{size} ({human_readable_size(size)})"
 
 
-@dataclasses.dataclass(kw_only=True)
+@dataclasses.dataclass(kw_only=True, frozen=True, slots=True)
 class ArrayInfo:
     """
     Visual summary for an Array.
@@ -79,6 +79,7 @@ class ArrayInfo:
     _type: Literal["Array"] = "Array"
     _zarr_format: ZarrFormat
     _data_type: np.dtype[Any] | DataType
+    _fill_value: object
     _shape: tuple[int, ...]
     _shard_shape: tuple[int, ...] | None = None
     _chunk_shape: tuple[int, ...] | None = None
@@ -97,6 +98,7 @@ def __repr__(self) -> str:
         Type               : {_type}
         Zarr format        : {_zarr_format}
         Data type          : {_data_type}
+        Fill value         : {_fill_value}
         Shape              : {_shape}""")
 
         if self._shard_shape is not None:
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1 @@
		Adds ``fill_value`` to the list of attributes displayed in the output of the ``AsyncArray.info()`` method.