Add sparsity structure enum (#197)

src/compressed_tensors/config/base.py

@@ -12,16 +12,17 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from enum import Enum
+from enum import Enum, unique
 from typing import List, Optional
 
 from compressed_tensors.registry import RegistryMixin
 from pydantic import BaseModel
 
 
-__all__ = ["SparsityCompressionConfig", "CompressionFormat"]
+__all__ = ["SparsityCompressionConfig", "CompressionFormat", "SparsityStructure"]
 
 
+@unique
 class CompressionFormat(Enum):
     dense = "dense"
     sparse_bitmask = "sparse-bitmask"
@@ -32,6 +33,63 @@ class CompressionFormat(Enum):
     marlin_24 = "marlin-24"
 
 
+@unique
+class SparsityStructure(Enum):
+    """
+    An enumeration to represent different sparsity structures.
+
+    Attributes
+    ----------
+    TWO_FOUR : str
+        Represents a 2:4 sparsity structure.
+    ZERO_ZERO : str
+        Represents a 0:0 sparsity structure.
+    UNSTRUCTURED : str
+        Represents an unstructured sparsity structure.
+
+    Examples
+    --------
+    >>> SparsityStructure('2:4')
+    <SparsityStructure.TWO_FOUR: '2:4'>
+
+    >>> SparsityStructure('unstructured')
+    <SparsityStructure.UNSTRUCTURED: 'unstructured'>
+
+    >>> SparsityStructure('2:4') == SparsityStructure.TWO_FOUR
+    True
+
+    >>> SparsityStructure('UNSTRUCTURED') == SparsityStructure.UNSTRUCTURED
+    True
+
+    >>> SparsityStructure(None) == SparsityStructure.UNSTRUCTURED
+    True
+
+    >>> SparsityStructure('invalid')
+    Traceback (most recent call last):
+        ...
+    ValueError: invalid is not a valid SparsityStructure
+    """
+
+    TWO_FOUR = "2:4"
+    UNSTRUCTURED = "unstructured"
+    ZERO_ZERO = "0:0"
+
+    def __new__(cls, value):
+        obj = object.__new__(cls)
+        obj._value_ = value.lower() if value is not None else value
+        return obj
+
+    @classmethod
+    def _missing_(cls, value):
+        # Handle None and case-insensitive values
+        if value is None:
+            return cls.UNSTRUCTURED
+        for member in cls:
+            if member.value == value.lower():
+                return member
+        raise ValueError(f"{value} is not a valid {cls.__name__}")
+
+
 class SparsityCompressionConfig(RegistryMixin, BaseModel):
     """
     Base data class for storing sparsity compression parameters

tests/test_configs/__init__.py

@@ -0,0 +1,13 @@
+# Copyright (c) 2021 - present / Neuralmagic, Inc. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.

tests/test_configs/test_base.py

@@ -0,0 +1,57 @@
+# Copyright (c) 2021 - present / Neuralmagic, Inc. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import pytest
+from compressed_tensors.config import SparsityStructure
+
+
+def test_sparsity_structure_valid_cases():
+    assert (
+        SparsityStructure("2:4") == SparsityStructure.TWO_FOUR
+    ), "Failed to match '2:4' with TWO_FOUR"
+    assert (
+        SparsityStructure("unstructured") == SparsityStructure.UNSTRUCTURED
+    ), "Failed to match 'unstructured' with UNSTRUCTURED"
+    assert (
+        SparsityStructure("UNSTRUCTURED") == SparsityStructure.UNSTRUCTURED
+    ), "Failed to match 'UNSTRUCTURED' with UNSTRUCTURED"
+    assert (
+        SparsityStructure(None) == SparsityStructure.UNSTRUCTURED
+    ), "Failed to match None with UNSTRUCTURED"
+
+
+def test_sparsity_structure_invalid_case():
+    with pytest.raises(ValueError, match="invalid is not a valid SparsityStructure"):
+        SparsityStructure("invalid")
+
+
+def test_sparsity_structure_case_insensitivity():
+    assert (
+        SparsityStructure("2:4") == SparsityStructure.TWO_FOUR
+    ), "Failed to match '2:4' with TWO_FOUR"
+    assert (
+        SparsityStructure("2:4".upper()) == SparsityStructure.TWO_FOUR
+    ), "Failed to match '2:4'.upper() with TWO_FOUR"
+    assert (
+        SparsityStructure("unstructured".upper()) == SparsityStructure.UNSTRUCTURED
+    ), "Failed to match 'unstructured'.upper() with UNSTRUCTURED"
+    assert (
+        SparsityStructure("UNSTRUCTURED".lower()) == SparsityStructure.UNSTRUCTURED
+    ), "Failed to match 'UNSTRUCTURED'.lower() with UNSTRUCTURED"
+
+
+def test_sparsity_structure_default_case():
+    assert (
+        SparsityStructure(None) == SparsityStructure.UNSTRUCTURED
+    ), "Failed to match None with UNSTRUCTURED"