Merge pull request #31 from p2p-ld/tests-combinatorics

[tests] `numpydantic.testing` - exposing helpers for 3rd-party interface development & combinatoric testing

.github/workflows/tests.yml

@@ -33,10 +33,10 @@ jobs:
     runs-on: ${{ matrix.platform }}
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
 
       - name: Set up python
-        uses: actions/setup-python@v4
+        uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.python-version }}
 

docs/_static/css/notebooks.css

@@ -0,0 +1,31 @@
+div.cell.tag_hide-cell details.above-input > summary,
+div.cell.tag_hide-input details.above-input > summary,
+div.cell.tag_hide-output details.below-input > summary{
+    background-color: var(--color-admonition-title-background--admonition-todo);
+    color: var(--color-content-foreground);
+    border: unset;
+    border-left: 2px solid var(--mystnb-source-margin-color);
+    opacity: unset;
+    padding: 0.25em 0 0.25em 1em;
+}
+
+div.cell.tag_hide-cell details.above-input > summary > span,
+div.cell.tag_hide-input details.above-input > summary > span,
+div.cell.tag_hide-output details.below-input > summary > span
+{
+    opacity: unset;
+}
+
+div.cell details.above-input div.cell_input {
+    border: unset;
+    background-color: unset;
+    border-left: 2px solid var(--mystnb-source-margin-color);
+}
+
+div.cell details.above-input div.cell_input div.highlight {
+    background: var(--color-admonition-background);
+}
+
+.output.text_html pre {
+    font-size: 0.8em;
+}

docs/api/testing/cases.md

@@ -0,0 +1,7 @@
+# cases
+
+```{eval-rst}
+.. automodule:: numpydantic.testing.cases
+    :members:
+    :undoc-members:
+```

docs/api/testing/helpers.md

@@ -0,0 +1,7 @@
+# helpers
+
+```{eval-rst}
+.. automodule:: numpydantic.testing.helpers
+    :members:
+    :undoc-members:
+```

docs/api/testing/index.md

@@ -0,0 +1,19 @@
+# testing
+
+Utilities for testing and 3rd-party interface development.
+
+See also the [narrative testing docs](../../contributing/testing.md)
+
+```{toctree}
+:maxdepth: 2
+
+cases
+helpers
+interfaces
+```
+
+```{eval-rst}
+.. automodule:: numpydantic.testing
+    :members:
+    :undoc-members:
+```

docs/api/testing/interfaces.md

@@ -0,0 +1,7 @@
+# interfaces
+
+```{eval-rst}
+.. automodule:: numpydantic.testing.interfaces
+    :members:
+    :undoc-members:
+```

docs/changelog.md

@@ -4,6 +4,33 @@
 
 ### 1.6.*
 
+#### 1.6.4 - 24-10-11 - Combinatoric Testing
+
+PR: https://github.com/p2p-ld/numpydantic/pull/31
+
+
+We have rewritten our testing system for more rigorous tests,
+where before we were limited to only testing dtype or shape cases one at a time,
+now we can test all possible combinations together!
+
+This allows us to have better guarantees for behavior that all interfaces
+should support, validating it against all possible dtypes and shapes.
+
+We also exposed all the helpers and array testing classes for downstream development
+so that it would be easier to test and validate any 3rd-party interfaces
+that haven't made their way into mainline numpydantic yet - 
+see the {mod}`numpydantic.testing` module.
+
+See the [testing documentation](./contributing/testing.md) for more details.
+
+**Bugfix**
+- Previously, numpy and dask arrays with a model dtype would fail json roundtripping
+  because they wouldn't be correctly cast back to the model type. Now they are.
+- Zarr would not dump the dtype of an array when it roundtripped to json,
+  causing every array to be interpreted as a random integer or float type.
+  `dtype` is now dumped and used when deserializing.
+
+
 #### 1.6.3 - 24-09-26
 
 **Bugfix**

docs/conf.py

@@ -49,6 +49,7 @@ intersphinx_mapping = {
 
 html_theme = "furo"
 html_static_path = ["_static"]
+html_css_files = ["css/notebooks.css"]
 
 # autodoc
 autodoc_pydantic_model_show_json_error_strategy = "coerce"

docs/contributing/coc.md

@@ -0,0 +1,5 @@
+# Code of Conduct
+
+```{todo}
+jonny write the code of conduct
+```

docs/contributing/index.md

@@ -0,0 +1,8 @@
+# Contributing
+
+```{toctree}
+coc
+process
+interface
+testing
+```

docs/contributing/interface.md

@@ -0,0 +1,5 @@
+# Writing an Interface
+
+```{todo}
+Jonny write the interface contrib docs
+```

docs/contributing/process.md

@@ -0,0 +1,15 @@
+# Contribution Process
+
+```{todo}
+Jonny write the contribution docs
+```
+
+### Issues
+
+### Development Environment
+
+### Testing
+
+### Linting
+
+### Pull Requests

docs/contributing/testing.md

@@ -0,0 +1,213 @@
+---
+file_format: mystnb
+mystnb:
+    output_stderr: remove
+    render_text_lexer: python
+    render_markdown_format: myst
+myst:
+    enable_extensions: ["colon_fence"]
+---
+# Testing
+
+```{code-cell}
+---
+tags: [hide-cell]
+---
+
+from pathlib import Path
+from rich.console import Console
+from rich.theme import Theme
+from rich.style import Style
+from rich.color import Color
+
+theme = Theme({
+    "repr.call": Style(color=Color.from_rgb(110,191,38), bold=True),
+    "repr.attrib_name": Style(color="slate_blue1"),
+    "repr.number": Style(color="deep_sky_blue1"),
+    "repr.none": Style(color="bright_magenta", italic=True),
+    "repr.attrib_name": Style(color="white"),
+    "repr.tag_contents": Style(color="light_steel_blue"),
+    "repr.str": Style(color="violet") 
+})
+console = Console(theme=theme)
+
+```
+
+```{note}
+Also see the [`numpydantic.testing` API docs](../api/testing/index.md)
+and the [Writing an Interface](../interfaces.md) guide
+```
+
+Numpydantic exposes a system for combinatoric testing across dtypes, shapes,
+and interfaces in the {mod}`numpydantic.testing` module.
+
+These helper classes and functions are included in the distributed package
+so they can be used for downstream development of independent interfaces
+(though we always welcome contributions!)
+
+## Validation Cases
+
+Each test case is parameterized by a {class}`.ValidationCase`. 
+
+The case is intended to be able to be partially filled in so that multiple
+validation cases can be merged together, but also used independently
+by falling back on default values.
+
+There are three major parts to a validation case:
+
+- **Annotation specification:** {attr}`~.ValidationCase.annotation_dtype` and
+  {attr}`~.ValidationCase.annotation_shape` specifies how the
+  {class}`.NDArray` {attr}`.ValidationCase.annotation` that is used to test
+  against is generated
+- **Array specification:** {attr}`~.ValidationCase.dtype` and {attr}`~.ValidationCase.shape`
+  specify that array that will be generated to test against the annotation
+- **Interface specification:** An {class}`.InterfaceCase` that refers to
+  an {class}`.Interface`, and provides array generation and other auxilary logic.
+
+Typically, one specifies a dtype along with an annotation dtype or
+a shape along with an annotation shape (or implicitly against the defaults for either),
+along with a value for `passes` that indicates if that combination is valid.
+
+```{code-cell}
+from numpydantic.testing import ValidationCase
+
+dtype_case = ValidationCase(
+    id="int_int", 
+    dtype=int, 
+    annotation_dtype=int, 
+    passes=True
+)
+shape_case = ValidationCase(
+    id="cool_shape", 
+    shape=(1,2,3), 
+    annotation_shape=(1,"*","2-4"), 
+    passes=True
+)
+
+merged = dtype_case.merge(shape_case)
+console.print(merged.model_dump(exclude={'annotation', 'model'}, exclude_unset=True))
+```
+
+When merging validation cases, the merged case only `passes` if all the
+original cases do.
+
+```{code-cell}
+from numpydantic.testing import ValidationCase
+
+dtype_case = ValidationCase(
+    id="int_int", 
+    dtype=int, 
+    annotation_dtype=int, 
+    passes=True
+)
+shape_case = ValidationCase(
+    id="uncool_shape", 
+    shape=(1,2,3), 
+    annotation_shape=(9,8,7), 
+    passes=False
+)
+
+merged = dtype_case.merge(shape_case)
+console.print(merged.model_dump(exclude={'annotation', 'model'}, exclude_unset=True))
+```
+
+We provide a convenience function {func}`.merged_product` for creating a merged product of
+multiple sets of test cases.
+
+For example, you may want to create a set of dtype and shape cases and validate
+against all combinations
+
+```{code-cell}
+from numpydantic.testing.helpers import merged_product
+
+dtype_cases = [
+    ValidationCase(dtype=int, annotation_dtype=int, passes=True),
+    ValidationCase(dtype=int, annotation_dtype=float, passes=False)
+]
+shape_cases = [
+    ValidationCase(shape=(1,2,3), annotation_shape=(1,2,3), passes=True),
+    ValidationCase(shape=(4,5,6), annotation_shape=(1,2,3), passes=False)
+]
+
+iterator = merged_product(dtype_cases, shape_cases)
+
+console.print([i.model_dump(exclude_unset=True, exclude={'model', 'annotation'}) for i in iterator])
+
+```
+
+You can pass constraints to the {func}`.merged_product` iterator to
+filter cases that match some value, for example to get only the cases that pass:
+
+```{code-cell}
+iterator = merged_product(dtype_cases, shape_cases, conditions={"passes": True})
+console.print([i.model_dump(exclude_unset=True, exclude={'model', 'annotation'}) for i in iterator])
+```
+
+## Interface Cases
+
+Validation cases can be paired with interface cases that handle
+generating arrays for the given interface from the specification in the
+validation case.
+
+Since some array interfaces like Zarr have multiple possible forms
+of an array (in memory, on disk, in a zip file, etc.) an interface
+may have multiple cases that are important to test against.
+
+The {meth}`.InterfaceCase.make_array` method does what you'd expect it to,
+creating an array, and returning the appropriate input type for the interface:
+
+```{code-cell}
+from numpydantic.testing.interfaces import NumpyCase, ZarrNestedCase
+
+NumpyCase.make_array(shape=(1,2,3), dtype=float)
+```
+
+```{code-cell}
+ZarrNestedCase.make_array(shape=(1,2,3), dtype=float, path=Path("__tmp__/zarr_dir"))
+```
+
+Interface cases also define when an interface should skip a given test
+parameterization. For example, some array formats can't support arbitrary
+object serialization, and the video class can only support 8-bit arrays
+of a specific shape
+
+```{code-cell}
+from numpydantic.testing.interfaces import VideoCase
+
+VideoCase.skip(shape=(1,1), dtype=float)
+```
+
+This, and the array generation methods are propagated up into 
+a ValidationCase that contains them
+
+```{code-cell}
+case = ValidationCase(shape=(1,2,3), dtype=float, interface=VideoCase)
+case.skip()
+```
+
+The {func}`.merged_product` iterator automatically excludes any
+combinations of interfaces and test parameterizations that should be skipped.
+
+## Making Fixtures
+
+Pytest fixtures are a useful way to re-use validation case products.
+To keep things tidy, you may want to use marks and ids when creating them
+so that you can run tests against specific interfaces or conditions
+with the `pytest -m mark` system.
+
+```python
+import pytest
+
+@pytest.fixture(
+    params=(
+        pytest.param(
+            p, 
+            id=p.id, 
+            marks=getattr(pytest.mark, p.interface.interface.name)
+        )
+        for p in iterator
+    )
+)
+def my_cases(request):
+    return request.param
+```

docs/index.md

@@ -514,6 +514,7 @@ api/meta
 api/schema
 api/serialization
 api/types
+api/testing/index
 
 ```
 
@@ -523,6 +524,7 @@ api/types
 :hidden: true
 
 changelog
+contributing/index
 development
 todo
 ```

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "numpydantic"
-version = "1.6.3"
+version = "1.6.4"
 description = "Type and shape validation and serialization for arbitrary array types in pydantic models"
 authors = [
     {name = "sneakers-the-rat", email = "sneakers-the-rat@protonmail.com"},
@@ -96,6 +96,12 @@ distribution = true
 
 [tool.pdm.build]
 includes = []
+
+[tool.pdm.scripts]
+lint = "ruff check"
+format = {shell = "ruff check --fix ; black ."}
+test = "pytest"
+
 [build-system]
 requires = ["pdm-backend"]
 build-backend = "pdm.backend"
@@ -125,10 +131,12 @@ markers = [
     "zarr: zarr interface",
 ]
 
+[tool.black]
+target-version = ["py39", "py310", "py311", "py312"]
+
 [tool.ruff]
 target-version = "py39"
-include = ["src/numpydantic/**/*.py", "pyproject.toml"]
+include = ["src/numpydantic/**/*.py", "tests/**/*.py", "pyproject.toml"]
-exclude = ["tests"]
 
 [tool.ruff.lint]
 select = [
@@ -177,6 +185,10 @@ ignore = [
 
 fixable = ["ALL"]
 
+[tool.ruff.lint.per-file-ignores]
+"src/numpydantic/testing/*" = ["D", "F722"]
+"tests/*" = ["D", "F403", "F722", "ANN", ]
+
 [tool.mypy]
 plugins = [
     "pydantic.mypy"

src/numpydantic/interface/__init__.py

@@ -3,7 +3,7 @@ Interfaces between nptyping types and array backends
 """
 
 from numpydantic.interface.dask import DaskInterface
-from numpydantic.interface.hdf5 import H5Interface
+from numpydantic.interface.hdf5 import H5ArrayPath, H5Interface
 from numpydantic.interface.interface import (
     Interface,
     InterfaceMark,
@@ -12,10 +12,11 @@ from numpydantic.interface.interface import (
 )
 from numpydantic.interface.numpy import NumpyInterface
 from numpydantic.interface.video import VideoInterface
-from numpydantic.interface.zarr import ZarrInterface
+from numpydantic.interface.zarr import ZarrArrayPath, ZarrInterface
 
 __all__ = [
     "DaskInterface",
+    "H5ArrayPath",
     "H5Interface",
     "Interface",
     "InterfaceMark",
@@ -23,5 +24,6 @@ __all__ = [
     "MarkedJson",
     "NumpyInterface",
     "VideoInterface",
+    "ZarrArrayPath",
     "ZarrInterface",
 ]

src/numpydantic/interface/dask.py

@@ -5,7 +5,7 @@ Interface for Dask arrays
 from typing import Any, Iterable, List, Literal, Optional, Union
 
 import numpy as np
-from pydantic import SerializationInfo
+from pydantic import BaseModel, SerializationInfo
 
 from numpydantic.interface.interface import Interface, JsonDict
 from numpydantic.types import DtypeType, NDArrayType
@@ -70,9 +70,33 @@ class DaskInterface(Interface):
         else:
             return False
 
+    def before_validation(self, array: DaskArray) -> NDArrayType:
+        """
+        Try and coerce dicts that should be model objects into the model objects
+        """
+        try:
+            if issubclass(self.dtype, BaseModel) and isinstance(
+                array.reshape(-1)[0].compute(), dict
+            ):
+
+                def _chunked_to_model(array: np.ndarray) -> np.ndarray:
+                    def _vectorized_to_model(item: Union[dict, BaseModel]) -> BaseModel:
+                        if not isinstance(item, self.dtype):
+                            return self.dtype(**item)
+                        else:  # pragma: no cover
+                            return item
+
+                    return np.vectorize(_vectorized_to_model)(array)
+
+                array = array.map_blocks(_chunked_to_model, dtype=self.dtype)
+        except TypeError:
+            # fine, dtype isn't a type
+            pass
+        return array
+
     def get_object_dtype(self, array: NDArrayType) -> DtypeType:
         """Dask arrays require a compute() call to retrieve a single value"""
-        return type(array.ravel()[0].compute())
+        return type(array.reshape(-1)[0].compute())
 
     @classmethod
     def enabled(cls) -> bool:

src/numpydantic/interface/numpy.py

@@ -4,7 +4,7 @@ Interface to numpy arrays
 
 from typing import Any, Literal, Union
 
-from pydantic import SerializationInfo
+from pydantic import BaseModel, SerializationInfo
 
 from numpydantic.interface.interface import Interface, JsonDict
 
@@ -59,6 +59,9 @@ class NumpyInterface(Interface):
         Check that this is in fact a numpy ndarray or something that can be
         coerced to one
         """
+        if array is None:
+            return False
+
         if isinstance(array, ndarray):
             return True
         elif isinstance(array, dict):
@@ -77,6 +80,14 @@ class NumpyInterface(Interface):
         """
         if not isinstance(array, ndarray):
             array = np.array(array)
+
+        try:
+            if issubclass(self.dtype, BaseModel) and isinstance(array.flat[0], dict):
+                array = np.vectorize(lambda x: self.dtype(**x))(array)
+        except TypeError:
+            # fine, dtype isn't a type
+            pass
+
         return array
 
     @classmethod

src/numpydantic/interface/zarr.py

@@ -63,6 +63,7 @@ class ZarrJsonDict(JsonDict):
     type: Literal["zarr"]
     file: Optional[str] = None
     path: Optional[str] = None
+    dtype: Optional[str] = None
     value: Optional[list] = None
 
     def to_array_input(self) -> Union[ZarrArray, ZarrArrayPath]:
@@ -73,7 +74,7 @@ class ZarrJsonDict(JsonDict):
         if self.file:
             array = ZarrArrayPath(file=self.file, path=self.path)
         else:
-            array = zarr.array(self.value)
+            array = zarr.array(self.value, dtype=self.dtype)
         return array
 
 
@@ -194,6 +195,7 @@ class ZarrInterface(Interface):
             is_file = False
 
             as_json = {"type": cls.name}
+            as_json["dtype"] = array.dtype.name
             if hasattr(array.store, "dir_path"):
                 is_file = True
                 as_json["file"] = array.store.dir_path()

src/numpydantic/ndarray.py

@@ -152,6 +152,8 @@ class NDArrayMeta(_NDArrayMeta, implementation="NDArray"):
             result = str(dtype)
         elif isinstance(dtype, tuple):
             result = ", ".join([str(dt) for dt in dtype])
+        else:
+            result = str(dtype)
         return result
 
 

src/numpydantic/serialization.py

@@ -80,7 +80,7 @@ def _relativize_paths(
             ):
                 return v
             return str(relative_path(path, relative_to))
-        except (TypeError, ValueError):
+        except (TypeError, ValueError, OSError):
             return v
 
     return _walk_and_apply(value, _r_path, skip)
@@ -95,7 +95,7 @@ def _absolutize_paths(value: dict, skip: Iterable = tuple()) -> dict:
             if not path.exists():
                 return v
             return str(path.resolve())
-        except (TypeError, ValueError):
+        except (TypeError, ValueError, OSError):
             return v
 
     return _walk_and_apply(value, _a_path, skip)

src/numpydantic/testing/__init__.py

@@ -0,0 +1,6 @@
+from numpydantic.testing.helpers import InterfaceCase, ValidationCase
+
+__all__ = [
+    "InterfaceCase",
+    "ValidationCase",
+]

src/numpydantic/testing/cases.py

@@ -0,0 +1,259 @@
+import sys
+from typing import Union
+
+import numpy as np
+from pydantic import BaseModel
+
+from numpydantic.dtype import Float, Integer, Number
+from numpydantic.testing.helpers import ValidationCase, merged_product
+from numpydantic.testing.interfaces import (
+    DaskCase,
+    HDF5Case,
+    HDF5CompoundCase,
+    NumpyCase,
+    VideoCase,
+    ZarrCase,
+    ZarrDirCase,
+    ZarrNestedCase,
+    ZarrZipCase,
+)
+
+if sys.version_info.minor >= 10:
+    from typing import TypeAlias
+
+    YES_PIPE = True
+else:
+    from typing_extensions import TypeAlias
+
+    YES_PIPE = False
+
+
+class BasicModel(BaseModel):
+    x: int
+
+
+class BadModel(BaseModel):
+    x: int
+
+
+class SubClass(BasicModel):
+    pass
+
+
+# --------------------------------------------------
+# Annotations
+# --------------------------------------------------
+
+RGB_UNION = (("*", "*"), ("*", "*", 3), ("*", "*", 3, 4))
+UNION_TYPE: TypeAlias = Union[np.uint32, np.float32]
+
+SHAPE_CASES = (
+    ValidationCase(shape=(10, 10, 2, 2), passes=True, id="valid shape"),
+    ValidationCase(shape=(10, 10, 2), passes=False, id="missing dimension"),
+    ValidationCase(shape=(10, 10, 2, 2, 2), passes=False, id="extra dimension"),
+    ValidationCase(shape=(11, 10, 2, 2), passes=False, id="dimension too large"),
+    ValidationCase(shape=(9, 10, 2, 2), passes=False, id="dimension too small"),
+    ValidationCase(shape=(10, 10, 1, 1), passes=True, id="wildcard smaller"),
+    ValidationCase(shape=(10, 10, 3, 3), passes=True, id="wildcard larger"),
+    ValidationCase(
+        annotation_shape=RGB_UNION, shape=(5, 5), passes=True, id="Union 2D"
+    ),
+    ValidationCase(
+        annotation_shape=RGB_UNION, shape=(5, 5, 3), passes=True, id="Union 3D"
+    ),
+    ValidationCase(
+        annotation_shape=RGB_UNION, shape=(5, 5, 3, 4), passes=True, id="Union 4D"
+    ),
+    ValidationCase(
+        annotation_shape=RGB_UNION,
+        shape=(5, 5, 4),
+        passes=False,
+        id="Union incorrect 3D",
+    ),
+    ValidationCase(
+        annotation_shape=RGB_UNION,
+        shape=(5, 5, 3, 6),
+        passes=False,
+        id="Union incorrect 4D",
+    ),
+    ValidationCase(
+        annotation_shape=RGB_UNION,
+        shape=(5, 5, 4, 6),
+        passes=False,
+        id="Union incorrect both",
+    ),
+)
+"""
+Base Shape cases
+"""
+
+
+DTYPE_CASES = [
+    ValidationCase(dtype=float, passes=True, id="float"),
+    ValidationCase(dtype=int, passes=False, id="int"),
+    ValidationCase(dtype=np.uint8, passes=False, id="uint8"),
+    ValidationCase(annotation_dtype=Number, dtype=int, passes=True, id="number-int"),
+    ValidationCase(
+        annotation_dtype=Number, dtype=float, passes=True, id="number-float"
+    ),
+    ValidationCase(
+        annotation_dtype=Number, dtype=np.uint8, passes=True, id="number-uint8"
+    ),
+    ValidationCase(
+        annotation_dtype=Number, dtype=np.float16, passes=True, id="number-float16"
+    ),
+    ValidationCase(annotation_dtype=Number, dtype=str, passes=False, id="number-str"),
+    ValidationCase(annotation_dtype=Integer, dtype=int, passes=True, id="integer-int"),
+    ValidationCase(
+        annotation_dtype=Integer, dtype=np.uint8, passes=True, id="integer-uint8"
+    ),
+    ValidationCase(
+        annotation_dtype=Integer, dtype=float, passes=False, id="integer-float"
+    ),
+    ValidationCase(
+        annotation_dtype=Integer, dtype=np.float32, passes=False, id="integer-float32"
+    ),
+    ValidationCase(annotation_dtype=Integer, dtype=str, passes=False, id="integer-str"),
+    ValidationCase(annotation_dtype=Float, dtype=float, passes=True, id="float-float"),
+    ValidationCase(
+        annotation_dtype=Float, dtype=np.float32, passes=True, id="float-float32"
+    ),
+    ValidationCase(annotation_dtype=Float, dtype=int, passes=False, id="float-int"),
+    ValidationCase(
+        annotation_dtype=Float, dtype=np.uint8, passes=False, id="float-uint8"
+    ),
+    ValidationCase(annotation_dtype=Float, dtype=str, passes=False, id="float-str"),
+    ValidationCase(annotation_dtype=str, dtype=str, passes=True, id="str-str"),
+    ValidationCase(annotation_dtype=str, dtype=int, passes=False, id="str-int"),
+    ValidationCase(annotation_dtype=str, dtype=float, passes=False, id="str-float"),
+    ValidationCase(
+        annotation_dtype=BasicModel, dtype=BasicModel, passes=True, id="model-model"
+    ),
+    ValidationCase(
+        annotation_dtype=BasicModel, dtype=BadModel, passes=False, id="model-badmodel"
+    ),
+    ValidationCase(
+        annotation_dtype=BasicModel, dtype=int, passes=False, id="model-int"
+    ),
+    ValidationCase(
+        annotation_dtype=BasicModel, dtype=SubClass, passes=True, id="model-subclass"
+    ),
+    ValidationCase(
+        annotation_dtype=UNION_TYPE,
+        dtype=np.uint32,
+        passes=True,
+        id="union-type-uint32",
+    ),
+    ValidationCase(
+        annotation_dtype=UNION_TYPE,
+        dtype=np.float32,
+        passes=True,
+        id="union-type-float32",
+    ),
+    ValidationCase(
+        annotation_dtype=UNION_TYPE,
+        dtype=np.uint64,
+        passes=False,
+        id="union-type-uint64",
+    ),
+    ValidationCase(
+        annotation_dtype=UNION_TYPE,
+        dtype=np.float64,
+        passes=False,
+        id="union-type-float64",
+    ),
+    ValidationCase(
+        annotation_dtype=UNION_TYPE, dtype=str, passes=False, id="union-type-str"
+    ),
+]
+"""
+Base Dtype cases
+"""
+
+
+if YES_PIPE:
+    UNION_PIPE: TypeAlias = np.uint32 | np.float32
+
+    DTYPE_CASES.extend(
+        [
+            ValidationCase(
+                annotation_dtype=UNION_PIPE,
+                dtype=np.uint32,
+                passes=True,
+                id="union-pipe-uint32",
+            ),
+            ValidationCase(
+                annotation_dtype=UNION_PIPE,
+                dtype=np.float32,
+                passes=True,
+                id="union-pipe-float32",
+            ),
+            ValidationCase(
+                annotation_dtype=UNION_PIPE,
+                dtype=np.uint64,
+                passes=False,
+                id="union-pipe-uint64",
+            ),
+            ValidationCase(
+                annotation_dtype=UNION_PIPE,
+                dtype=np.float64,
+                passes=False,
+                id="union-pipe-float64",
+            ),
+            ValidationCase(
+                annotation_dtype=UNION_PIPE,
+                dtype=str,
+                passes=False,
+                id="union-pipe-str",
+            ),
+        ]
+    )
+
+INTERFACE_CASES = [
+    ValidationCase(interface=NumpyCase, id="numpy"),
+    ValidationCase(interface=HDF5Case, id="hdf5"),
+    ValidationCase(interface=HDF5CompoundCase, id="hdf5_compound"),
+    ValidationCase(interface=DaskCase, id="dask"),
+    ValidationCase(interface=ZarrCase, id="zarr"),
+    ValidationCase(interface=ZarrDirCase, id="zarr_dir"),
+    ValidationCase(interface=ZarrZipCase, id="zarr_zip"),
+    ValidationCase(interface=ZarrNestedCase, id="zarr_nested"),
+    ValidationCase(interface=VideoCase, id="video"),
+]
+"""
+All the interface cases
+"""
+
+
+DTYPE_AND_SHAPE_CASES = merged_product(SHAPE_CASES, DTYPE_CASES)
+"""
+Merged product of dtype and shape cases
+"""
+DTYPE_AND_SHAPE_CASES_PASSING = merged_product(
+    SHAPE_CASES, DTYPE_CASES, conditions={"passes": True}
+)
+"""
+Merged product of dtype and shape cases that are valid
+"""
+
+DTYPE_AND_INTERFACE_CASES = merged_product(INTERFACE_CASES, DTYPE_CASES)
+"""
+Merged product of dtype and interface cases
+"""
+DTYPE_AND_INTERFACE_CASES_PASSING = merged_product(
+    INTERFACE_CASES, DTYPE_CASES, conditions={"passes": True}
+)
+"""
+Merged product of dtype and interface cases that pass
+"""
+
+ALL_CASES = merged_product(SHAPE_CASES, DTYPE_CASES, INTERFACE_CASES)
+"""
+Merged product of all cases - dtype, shape, and interface
+"""
+ALL_CASES_PASSING = merged_product(
+    SHAPE_CASES, DTYPE_CASES, INTERFACE_CASES, conditions={"passes": True}
+)
+"""
+Merged product of all cases, but only those that pass
+"""

src/numpydantic/testing/helpers.py

@@ -0,0 +1,317 @@
+from abc import ABC, abstractmethod
+from collections.abc import Sequence
+from functools import reduce
+from itertools import product
+from operator import ior
+from pathlib import Path
+from typing import Generator, List, Literal, Optional, Tuple, Type, Union
+
+import numpy as np
+from pydantic import BaseModel, ConfigDict, ValidationError, computed_field
+
+from numpydantic import NDArray, Shape
+from numpydantic.dtype import Float
+from numpydantic.interface import Interface
+from numpydantic.types import DtypeType, NDArrayType
+
+
+class InterfaceCase(ABC):
+    """
+    An interface test helper that allows a given interface to generate and validate
+    arrays in one of its formats.
+
+    Each instance of "interface test case" should be considered one of the
+    potentially multiple realizations of a given interface.
+    If an interface has multiple formats (eg. zarr's different `store` s),
+    then it should have several test helpers.
+    """
+
+    @property
+    @abstractmethod
+    def interface(self) -> Interface:
+        """The interface that this helper is for"""
+
+    @classmethod
+    def array_from_case(
+        cls, case: "ValidationCase", path: Optional[Path] = None
+    ) -> Optional[NDArrayType]:
+        """
+        Generate an array from the given validation case.
+
+        Returns ``None`` if an array can't be generated for a specific case.
+        """
+        return cls.make_array(shape=case.shape, dtype=case.dtype, path=path)
+
+    @classmethod
+    @abstractmethod
+    def make_array(
+        cls,
+        shape: Tuple[int, ...] = (10, 10),
+        dtype: DtypeType = float,
+        path: Optional[Path] = None,
+        array: Optional[NDArrayType] = None,
+    ) -> Optional[NDArrayType]:
+        """
+        Make an array from a shape and dtype, and a path if needed
+
+        Args:
+            shape: shape of the array
+            dtype: dtype of the array
+            path: Path, if needed to generate on disk
+            array: Rather than passing shape and dtype, pass a literal arraylike thing
+        """
+
+    @classmethod
+    def validate_case(cls, case: "ValidationCase", path: Path) -> bool:
+        """
+        Validate a generated array against the annotation in the validation case.
+
+        Kept in the InterfaceCase in case an interface has specific
+        needs aside from just validating against a model, but typically left as is.
+
+        If an array can't be generated for a given case, returns `None`
+        so that the calling function can know to skip rather than fail the case.
+
+        Raises exceptions if validation fails (or succeeds when it shouldn't)
+
+        Args:
+            case (ValidationCase): The validation case to validate.
+            path (Path): Path to generate arrays into, if any.
+
+        Returns:
+            ``True`` if array is valid and was supposed to be,
+                or invalid and wasn't supposed to be
+        """
+        import pytest
+
+        array = cls.array_from_case(case, path)
+        if array is None:
+            pytest.skip()
+        if case.passes:
+            case.model(array=array)
+            return True
+        else:
+            with pytest.raises(ValidationError):
+                case.model(array=array)
+            return True
+
+    @classmethod
+    def skip(cls, shape: Tuple[int, ...], dtype: DtypeType) -> bool:
+        """
+        Whether a given interface should be skipped for the case
+        """
+        # Assume an interface case is valid for all other cases
+        return False
+
+
+_a_shape_type = Tuple[Union[int, Literal["*"], Literal["..."]], ...]
+
+
+class ValidationCase(BaseModel):
+    """
+    Test case for validating an array.
+
+    Contains both the validating model and the parameterization for an array to
+    test in a given interface
+    """
+
+    id: Optional[str] = None
+    """
+    String identifying the validation case
+    """
+    annotation_shape: Union[
+        Tuple[Union[int, str], ...], Tuple[Tuple[Union[int, str], ...], ...]
+    ] = (10, 10, "*", "*")
+    """
+    Shape to use in computed annotation used to validate against
+    """
+    annotation_dtype: Union[DtypeType, Sequence[DtypeType]] = Float
+    """
+    Dtype to use in computed annotation used to validate against
+    """
+    shape: Tuple[int, ...] = (10, 10, 2, 2)
+    """Shape of the array to validate"""
+    dtype: Union[Type, np.dtype] = float
+    """Dtype of the array to validate"""
+    passes: bool = False
+    """Whether the validation should pass or not"""
+    interface: Optional[Type[InterfaceCase]] = None
+    """The interface test case to generate and validate the array with"""
+    path: Optional[Path] = None
+    """The path to generate arrays into, if any."""
+
+    model_config = ConfigDict(arbitrary_types_allowed=True)
+
+    @computed_field()
+    def annotation(self) -> NDArray:
+        """
+        Annotation used in the model we validate against
+        """
+        # make a union type if we need to
+        shape_union = all(isinstance(s, Sequence) for s in self.annotation_shape)
+        dtype_union = isinstance(self.annotation_dtype, Sequence) and all(
+            isinstance(s, Sequence) for s in self.annotation_dtype
+        )
+        if shape_union or dtype_union:
+            shape_iter = (
+                self.annotation_shape if shape_union else [self.annotation_shape]
+            )
+            dtype_iter = (
+                self.annotation_dtype if dtype_union else [self.annotation_dtype]
+            )
+            annotations: List[type] = []
+            for shape, dtype in product(shape_iter, dtype_iter):
+                shape_str = ", ".join([str(i) for i in shape])
+                annotations.append(NDArray[Shape[shape_str], dtype])
+            return Union[tuple(annotations)]
+
+        else:
+            shape_str = ", ".join([str(i) for i in self.annotation_shape])
+            return NDArray[Shape[shape_str], self.annotation_dtype]
+
+    @computed_field()
+    def model(self) -> Type[BaseModel]:
+        """A model with a field ``array`` with the given annotation"""
+        annotation = self.annotation
+
+        class Model(BaseModel):
+            array: annotation
+
+        return Model
+
+    def validate_case(self, path: Optional[Path] = None) -> bool:
+        """
+        Whether the generated array correctly validated against the annotation,
+        given the interface
+
+        Args:
+            path (:class:`pathlib.Path`): Directory to generate array into, if on disk.
+
+        Raises:
+            ValueError: if an ``interface`` is missing
+        """
+        if self.interface is None:  # pragma: no cover
+            raise ValueError("Missing an interface")
+        if path is None:
+            if self.path:
+                path = self.path
+            else:  # pragma: no cover
+                raise ValueError("Missing a path to generate arrays into")
+
+        return self.interface.validate_case(self, path)
+
+    def array(self, path: Path) -> NDArrayType:
+        """Generate an array for the validation case if we have an interface to do so"""
+        if self.interface is None:  # pragma: no cover
+            raise ValueError("Missing an interface")
+        if path is None:  # pragma: no cover
+            if self.path:
+                path = self.path
+            else:
+                raise ValueError("Missing a path to generate arrays into")
+
+        return self.interface.array_from_case(self, path)
+
+    def merge(
+        self, other: Union["ValidationCase", Sequence["ValidationCase"]]
+    ) -> "ValidationCase":
+        """
+        Merge two validation cases
+
+        Dump both, excluding any unset fields, and merge, preferring `other`.
+
+        ``valid`` is ``True`` if and only if it is ``True`` in both.
+        """
+        if isinstance(other, Sequence):
+            return merge_cases(self, *other)
+        else:
+            return merge_cases(self, other)
+
+    def skip(self) -> bool:
+        """
+        Whether this case should be skipped
+        (eg. due to the interface case being incompatible
+        with the requested dtype or shape)
+        """
+        return bool(
+            self.interface is not None and self.interface.skip(self.shape, self.dtype)
+        )
+
+
+def merge_cases(*args: ValidationCase) -> ValidationCase:
+    """
+    Merge multiple validation cases
+    """
+    if len(args) == 1:  # pragma: no cover
+        return args[0]
+
+    dumped = [
+        m.model_dump(exclude_unset=True, exclude={"model", "annotation"}) for m in args
+    ]
+
+    # self_dump = self.model_dump(exclude_unset=True)
+    # other_dump = other.model_dump(exclude_unset=True)
+
+    # dumps might not have set `passes`, use only the ones that have
+    passes = [v.get("passes") for v in dumped if "passes" in v]
+    passes = all(passes)
+
+    # combine ids if present
+    ids = "-".join([str(v.get("id")) for v in dumped if "id" in v])
+
+    # merge dicts
+    merged = reduce(ior, dumped, {})
+    merged["passes"] = passes
+    merged["id"] = ids
+    return ValidationCase.model_construct(**merged)
+
+
+def merged_product(
+    *args: Sequence[ValidationCase], conditions: dict = None
+) -> Generator[ValidationCase, None, None]:
+    """
+    Generator for the product of the iterators of validation cases,
+    merging each tuple, and respecting if they should be :meth:`.ValidationCase.skip`
+    or not.
+
+    Examples:
+
+        .. code-block:: python
+
+            shape_cases = [
+                ValidationCase(shape=(10, 10, 10), passes=True, id="valid shape"),
+                ValidationCase(shape=(10, 10), passes=False, id="missing dimension"),
+            ]
+            dtype_cases = [
+                ValidationCase(dtype=float, passes=True, id="float"),
+                ValidationCase(dtype=int, passes=False, id="int"),
+            ]
+
+            iterator = merged_product(shape_cases, dtype_cases))
+            next(iterator)
+            # ValidationCase(
+            #     shape=(10, 10, 10),
+            #     dtype=float,
+            #     passes=True,
+            #     id="valid shape-float"
+            # )
+            next(iterator)
+            # ValidationCase(
+            #     shape=(10, 10, 10),
+            #     dtype=int,
+            #     passes=False,
+            #     id="valid shape-int"
+            # )
+
+
+    """
+    iterator = product(*args)
+    for case_tuple in iterator:
+        case = merge_cases(*case_tuple)
+        if case.skip():
+            continue
+        if conditions:
+            matching = all([getattr(case, k, None) == v for k, v in conditions.items()])
+            if not matching:
+                continue
+        yield case

src/numpydantic/testing/interfaces.py

@@ -0,0 +1,295 @@
+from datetime import datetime, timezone
+from pathlib import Path
+from typing import Optional, Tuple
+
+import cv2
+import dask.array as da
+import h5py
+import numpy as np
+import zarr
+from pydantic import BaseModel
+
+from numpydantic.interface import (
+    DaskInterface,
+    H5ArrayPath,
+    H5Interface,
+    NumpyInterface,
+    VideoInterface,
+    ZarrArrayPath,
+    ZarrInterface,
+)
+from numpydantic.testing.helpers import InterfaceCase
+from numpydantic.types import DtypeType, NDArrayType
+
+
+class NumpyCase(InterfaceCase):
+    """In-memory numpy array"""
+
+    interface = NumpyInterface
+
+    @classmethod
+    def make_array(
+        cls,
+        shape: Tuple[int, ...] = (10, 10),
+        dtype: DtypeType = float,
+        path: Optional[Path] = None,
+        array: Optional[NDArrayType] = None,
+    ) -> np.ndarray:
+        if array is not None:
+            return np.array(array, dtype=dtype)
+        elif issubclass(dtype, BaseModel):
+            return np.full(shape=shape, fill_value=dtype(x=1))
+        else:
+            return np.zeros(shape=shape, dtype=dtype)
+
+
+class _HDF5MetaCase(InterfaceCase):
+    """Base case for hdf5 cases"""
+
+    interface = H5Interface
+
+    @classmethod
+    def skip(cls, shape: Tuple[int, ...], dtype: DtypeType) -> bool:
+        return issubclass(dtype, BaseModel)
+
+
+class HDF5Case(_HDF5MetaCase):
+    """HDF5 Array"""
+
+    @classmethod
+    def make_array(
+        cls,
+        shape: Tuple[int, ...] = (10, 10),
+        dtype: DtypeType = float,
+        path: Optional[Path] = None,
+        array: Optional[NDArrayType] = None,
+    ) -> Optional[H5ArrayPath]:
+        if cls.skip(shape, dtype):  # pragma: no cover
+            return None
+
+        hdf5_file = path / "h5f.h5"
+        array_path = "/" + "_".join([str(s) for s in shape]) + "__" + dtype.__name__
+        generator = np.random.default_rng()
+
+        if array is not None:
+            data = np.array(array, dtype=dtype)
+        elif dtype is str:
+            data = generator.random(shape).astype(bytes)
+        elif dtype is datetime:
+            data = np.empty(shape, dtype="S32")
+            data.fill(datetime.now(timezone.utc).isoformat().encode("utf-8"))
+        else:
+            data = generator.random(shape).astype(dtype)
+
+        h5path = H5ArrayPath(hdf5_file, array_path)
+
+        with h5py.File(hdf5_file, "w") as h5f:
+            _ = h5f.create_dataset(array_path, data=data)
+        return h5path
+
+
+class HDF5CompoundCase(_HDF5MetaCase):
+    """HDF5 Array with a fake compound dtype"""
+
+    @classmethod
+    def make_array(
+        cls,
+        shape: Tuple[int, ...] = (10, 10),
+        dtype: DtypeType = float,
+        path: Optional[Path] = None,
+        array: Optional[NDArrayType] = None,
+    ) -> Optional[H5ArrayPath]:
+        if cls.skip(shape, dtype):  # pragma: no cover
+            return None
+
+        hdf5_file = path / "h5f.h5"
+        array_path = "/" + "_".join([str(s) for s in shape]) + "__" + dtype.__name__
+        if array is not None:
+            data = np.array(array, dtype=dtype)
+        elif dtype is str:
+            dt = np.dtype([("data", np.dtype("S10")), ("extra", "i8")])
+            data = np.array([("hey", 0)] * np.prod(shape), dtype=dt).reshape(shape)
+        elif dtype is datetime:
+            dt = np.dtype([("data", np.dtype("S32")), ("extra", "i8")])
+            data = np.array(
+                [(datetime.now(timezone.utc).isoformat().encode("utf-8"), 0)]
+                * np.prod(shape),
+                dtype=dt,
+            ).reshape(shape)
+        else:
+            dt = np.dtype([("data", dtype), ("extra", "i8")])
+            data = np.zeros(shape, dtype=dt)
+        h5path = H5ArrayPath(hdf5_file, array_path, "data")
+
+        with h5py.File(hdf5_file, "w") as h5f:
+            _ = h5f.create_dataset(array_path, data=data)
+        return h5path
+
+
+class DaskCase(InterfaceCase):
+    """In-memory dask array"""
+
+    interface = DaskInterface
+
+    @classmethod
+    def make_array(
+        cls,
+        shape: Tuple[int, ...] = (10, 10),
+        dtype: DtypeType = float,
+        path: Optional[Path] = None,
+        array: Optional[NDArrayType] = None,
+    ) -> da.Array:
+        if array is not None:
+            return da.array(array, dtype=dtype)
+        if issubclass(dtype, BaseModel):
+            return da.full(shape=shape, fill_value=dtype(x=1), chunks=-1)
+        else:
+            return da.zeros(shape=shape, dtype=dtype, chunks=10)
+
+
+class _ZarrMetaCase(InterfaceCase):
+    """Shared classmethods for zarr cases"""
+
+    interface = ZarrInterface
+
+    @classmethod
+    def skip(cls, shape: Tuple[int, ...], dtype: DtypeType) -> bool:
+        return issubclass(dtype, BaseModel) or dtype is str
+
+
+class ZarrCase(_ZarrMetaCase):
+    """In-memory zarr array"""
+
+    @classmethod
+    def make_array(
+        cls,
+        shape: Tuple[int, ...] = (10, 10),
+        dtype: DtypeType = float,
+        path: Optional[Path] = None,
+        array: Optional[NDArrayType] = None,
+    ) -> Optional[zarr.Array]:
+        if array is not None:
+            return zarr.array(array, dtype=dtype, chunks=-1)
+        else:
+            return zarr.zeros(shape=shape, dtype=dtype)
+
+
+class ZarrDirCase(_ZarrMetaCase):
+    """On-disk zarr array"""
+
+    @classmethod
+    def make_array(
+        cls,
+        shape: Tuple[int, ...] = (10, 10),
+        dtype: DtypeType = float,
+        path: Optional[Path] = None,
+        array: Optional[NDArrayType] = None,
+    ) -> Optional[zarr.Array]:
+        store = zarr.DirectoryStore(str(path / "array.zarr"))
+        if array is not None:
+            return zarr.array(array, dtype=dtype, store=store, chunks=-1)
+        else:
+            return zarr.zeros(shape=shape, dtype=dtype, store=store)
+
+
+class ZarrZipCase(_ZarrMetaCase):
+    """Zarr zip store"""
+
+    @classmethod
+    def make_array(
+        cls,
+        shape: Tuple[int, ...] = (10, 10),
+        dtype: DtypeType = float,
+        path: Optional[Path] = None,
+        array: Optional[NDArrayType] = None,
+    ) -> Optional[zarr.Array]:
+        store = zarr.ZipStore(str(path / "array.zarr"), mode="w")
+        if array is not None:
+            return zarr.array(array, dtype=dtype, store=store, chunks=-1)
+        else:
+            return zarr.zeros(shape=shape, dtype=dtype, store=store)
+
+
+class ZarrNestedCase(_ZarrMetaCase):
+    """Nested zarr array"""
+
+    @classmethod
+    def make_array(
+        cls,
+        shape: Tuple[int, ...] = (10, 10),
+        dtype: DtypeType = float,
+        path: Optional[Path] = None,
+        array: Optional[NDArrayType] = None,
+    ) -> ZarrArrayPath:
+        file = str(path / "nested.zarr")
+        root = zarr.open(file, mode="w")
+        subpath = "a/b/c"
+        if array is not None:
+            _ = root.array(subpath, array, dtype=dtype)
+        else:
+            _ = root.zeros(subpath, shape=shape, dtype=dtype)
+        return ZarrArrayPath(file=file, path=subpath)
+
+
+class VideoCase(InterfaceCase):
+    """AVI video"""
+
+    interface = VideoInterface
+
+    @classmethod
+    def make_array(
+        cls,
+        shape: Tuple[int, ...] = (10, 10, 10, 3),
+        dtype: DtypeType = np.uint8,
+        path: Optional[Path] = None,
+        array: Optional[NDArrayType] = None,
+    ) -> Optional[Path]:
+        if cls.skip(shape, dtype):  # pragma: no cover
+            return None
+
+        if array is not None:
+            array = np.array(array, dtype=np.uint8)
+            shape = array.shape
+
+        is_color = len(shape) == 4
+        frames = shape[0]
+        frame_shape = shape[1:]
+
+        video_path = path / "test.avi"
+        writer = cv2.VideoWriter(
+            str(video_path),
+            cv2.VideoWriter_fourcc(*"RGBA"),  # raw video for testing purposes
+            30,
+            (frame_shape[1], frame_shape[0]),
+            is_color,
+        )
+        for i in range(frames):
+            if array is not None:
+                frame = array[i]
+            else:
+                # make fresh array every time bc opencv eats them
+                frame = np.full(frame_shape, fill_value=i, dtype=np.uint8)
+            writer.write(frame)
+        writer.release()
+        return video_path
+
+    @classmethod
+    def skip(cls, shape: Tuple[int, ...], dtype: DtypeType) -> bool:
+        """
+        We really can only handle 4 dimensional cases in 8-bit rn lol
+
+        .. todo::
+
+            Fix shape/writing for grayscale videos
+
+        """
+        if len(shape) != 4:
+            return True
+
+        # if len(shape) < 3 or len(shape) > 4:
+        #     return True
+        if dtype not in (int, np.uint8):
+            return True
+        # if we have a color video (ie. shape == 4, needs to be RGB)
+        if len(shape) == 4 and shape[3] != 3:
+            return True

tests/conftest.py

@@ -1,25 +1,9 @@
-import sys
-
 import pytest
-from typing import Any, Tuple, Union, Type
-
-from pydantic import BaseModel, computed_field, ConfigDict
-from numpydantic import NDArray, Shape
-from numpydantic.ndarray import NDArrayMeta
-from numpydantic.dtype import Float, Number, Integer
-import numpy as np
 
+from numpydantic.testing.cases import DTYPE_CASES, SHAPE_CASES
+from numpydantic.testing.helpers import ValidationCase
 from tests.fixtures import *
 
-if sys.version_info.minor >= 10:
-    from typing import TypeAlias
-
-    YES_PIPE = True
-else:
-    from typing_extensions import TypeAlias
-
-    YES_PIPE = False
-
 
 def pytest_addoption(parser):
     parser.addoption(
@@ -29,191 +13,19 @@ def pytest_addoption(parser):
     )
 
 
-class ValidationCase(BaseModel):
+@pytest.fixture(
-    """
+    scope="function", params=[pytest.param(c, id=c.id) for c in SHAPE_CASES]
-    Test case for validating an array.
+)
-
+def shape_cases(request, tmp_output_dir_func) -> ValidationCase:
-    Contains both the validating model and the parameterization for an array to
+    case: ValidationCase = request.param.model_copy()
-    test in a given interface
+    case.path = tmp_output_dir_func
-    """
+    return case
-
-    annotation: Any = NDArray[Shape["10, 10, *"], Float]
-    """
-    Array annotation used in the validating model
-    Any typed because the types of type annotations are weird
-    """
-    shape: Tuple[int, ...] = (10, 10, 10)
-    """Shape of the array to validate"""
-    dtype: Union[Type, np.dtype] = float
-    """Dtype of the array to validate"""
-    passes: bool
-    """Whether the validation should pass or not"""
-
-    model_config = ConfigDict(arbitrary_types_allowed=True)
-
-    @computed_field()
-    def model(self) -> Type[BaseModel]:
-        """A model with a field ``array`` with the given annotation"""
-        annotation = self.annotation
-
-        class Model(BaseModel):
-            array: annotation
-
-        return Model
-
-
-class BasicModel(BaseModel):
-    x: int
-
-
-class BadModel(BaseModel):
-    x: int
-
-
-class SubClass(BasicModel):
-    pass
-
-
-RGB_UNION: TypeAlias = Union[
-    NDArray[Shape["* x, * y"], Number],
-    NDArray[Shape["* x, * y, 3 r_g_b"], Number],
-    NDArray[Shape["* x, * y, 3 r_g_b, 4 r_g_b_a"], Number],
-]
-
-NUMBER: TypeAlias = NDArray[Shape["*, *, *"], Number]
-INTEGER: TypeAlias = NDArray[Shape["*, *, *"], Integer]
-FLOAT: TypeAlias = NDArray[Shape["*, *, *"], Float]
-STRING: TypeAlias = NDArray[Shape["*, *, *"], str]
-MODEL: TypeAlias = NDArray[Shape["*, *, *"], BasicModel]
-UNION_TYPE: TypeAlias = NDArray[Shape["*, *, *"], Union[np.uint32, np.float32]]
-if YES_PIPE:
-    UNION_PIPE: TypeAlias = NDArray[Shape["*, *, *"], np.uint32 | np.float32]
 
 
 @pytest.fixture(
-    scope="module",
+    scope="function", params=[pytest.param(c, id=c.id) for c in DTYPE_CASES]
-    params=[
-        ValidationCase(shape=(10, 10, 10), passes=True),
-        ValidationCase(shape=(10, 10), passes=False),
-        ValidationCase(shape=(10, 10, 10, 10), passes=False),
-        ValidationCase(shape=(11, 10, 10), passes=False),
-        ValidationCase(shape=(9, 10, 10), passes=False),
-        ValidationCase(shape=(10, 10, 9), passes=True),
-        ValidationCase(shape=(10, 10, 11), passes=True),
-        ValidationCase(annotation=RGB_UNION, shape=(5, 5), passes=True),
-        ValidationCase(annotation=RGB_UNION, shape=(5, 5, 3), passes=True),
-        ValidationCase(annotation=RGB_UNION, shape=(5, 5, 3, 4), passes=True),
-        ValidationCase(annotation=RGB_UNION, shape=(5, 5, 4), passes=False),
-        ValidationCase(annotation=RGB_UNION, shape=(5, 5, 3, 6), passes=False),
-        ValidationCase(annotation=RGB_UNION, shape=(5, 5, 4, 6), passes=False),
-    ],
-    ids=[
-        "valid shape",
-        "missing dimension",
-        "extra dimension",
-        "dimension too large",
-        "dimension too small",
-        "wildcard smaller",
-        "wildcard larger",
-        "Union 2D",
-        "Union 3D",
-        "Union 4D",
-        "Union incorrect 3D",
-        "Union incorrect 4D",
-        "Union incorrect both",
-    ],
 )
-def shape_cases(request) -> ValidationCase:
+def dtype_cases(request, tmp_output_dir_func) -> ValidationCase:
-    return request.param
+    case: ValidationCase = request.param.model_copy()
-
+    case.path = tmp_output_dir_func
-
+    return case
-DTYPE_CASES = [
-    ValidationCase(dtype=float, passes=True),
-    ValidationCase(dtype=int, passes=False),
-    ValidationCase(dtype=np.uint8, passes=False),
-    ValidationCase(annotation=NUMBER, dtype=int, passes=True),
-    ValidationCase(annotation=NUMBER, dtype=float, passes=True),
-    ValidationCase(annotation=NUMBER, dtype=np.uint8, passes=True),
-    ValidationCase(annotation=NUMBER, dtype=np.float16, passes=True),
-    ValidationCase(annotation=NUMBER, dtype=str, passes=False),
-    ValidationCase(annotation=INTEGER, dtype=int, passes=True),
-    ValidationCase(annotation=INTEGER, dtype=np.uint8, passes=True),
-    ValidationCase(annotation=INTEGER, dtype=float, passes=False),
-    ValidationCase(annotation=INTEGER, dtype=np.float32, passes=False),
-    ValidationCase(annotation=INTEGER, dtype=str, passes=False),
-    ValidationCase(annotation=FLOAT, dtype=float, passes=True),
-    ValidationCase(annotation=FLOAT, dtype=np.float32, passes=True),
-    ValidationCase(annotation=FLOAT, dtype=int, passes=False),
-    ValidationCase(annotation=FLOAT, dtype=np.uint8, passes=False),
-    ValidationCase(annotation=FLOAT, dtype=str, passes=False),
-    ValidationCase(annotation=STRING, dtype=str, passes=True),
-    ValidationCase(annotation=STRING, dtype=int, passes=False),
-    ValidationCase(annotation=STRING, dtype=float, passes=False),
-    ValidationCase(annotation=MODEL, dtype=BasicModel, passes=True),
-    ValidationCase(annotation=MODEL, dtype=BadModel, passes=False),
-    ValidationCase(annotation=MODEL, dtype=int, passes=False),
-    ValidationCase(annotation=MODEL, dtype=SubClass, passes=True),
-    ValidationCase(annotation=UNION_TYPE, dtype=np.uint32, passes=True),
-    ValidationCase(annotation=UNION_TYPE, dtype=np.float32, passes=True),
-    ValidationCase(annotation=UNION_TYPE, dtype=np.uint64, passes=False),
-    ValidationCase(annotation=UNION_TYPE, dtype=np.float64, passes=False),
-    ValidationCase(annotation=UNION_TYPE, dtype=str, passes=False),
-]
-
-DTYPE_IDS = [
-    "float",
-    "int",
-    "uint8",
-    "number-int",
-    "number-float",
-    "number-uint8",
-    "number-float16",
-    "number-str",
-    "integer-int",
-    "integer-uint8",
-    "integer-float",
-    "integer-float32",
-    "integer-str",
-    "float-float",
-    "float-float32",
-    "float-int",
-    "float-uint8",
-    "float-str",
-    "str-str",
-    "str-int",
-    "str-float",
-    "model-model",
-    "model-badmodel",
-    "model-int",
-    "model-subclass",
-    "union-type-uint32",
-    "union-type-float32",
-    "union-type-uint64",
-    "union-type-float64",
-    "union-type-str",
-]
-
-if YES_PIPE:
-    DTYPE_CASES.extend(
-        [
-            ValidationCase(annotation=UNION_PIPE, dtype=np.uint32, passes=True),
-            ValidationCase(annotation=UNION_PIPE, dtype=np.float32, passes=True),
-            ValidationCase(annotation=UNION_PIPE, dtype=np.uint64, passes=False),
-            ValidationCase(annotation=UNION_PIPE, dtype=np.float64, passes=False),
-            ValidationCase(annotation=UNION_PIPE, dtype=str, passes=False),
-        ]
-    )
-    DTYPE_IDS.extend(
-        [
-            "union-pipe-uint32",
-            "union-pipe-float32",
-            "union-pipe-uint64",
-            "union-pipe-float64",
-            "union-pipe-str",
-        ]
-    )
-
-
-@pytest.fixture(scope="module", params=DTYPE_CASES, ids=DTYPE_IDS)
-def dtype_cases(request) -> ValidationCase:
-    return request.param

tests/fixtures.py

@@ -1,197 +0,0 @@
-import shutil
-from pathlib import Path
-from typing import Any, Callable, Optional, Tuple, Type, Union
-from warnings import warn
-from datetime import datetime, timezone
-
-import h5py
-import numpy as np
-import pytest
-from pydantic import BaseModel, Field
-import zarr
-import cv2
-
-from numpydantic.interface.hdf5 import H5ArrayPath
-from numpydantic.interface.zarr import ZarrArrayPath
-from numpydantic import NDArray, Shape
-from numpydantic.maps import python_to_nptyping
-from numpydantic.dtype import Number
-
-
-@pytest.fixture(scope="session")
-def tmp_output_dir(request: pytest.FixtureRequest) -> Path:
-    path = Path(__file__).parent.resolve() / "__tmp__"
-    if path.exists():
-        shutil.rmtree(str(path))
-    path.mkdir()
-
-    yield path
-
-    if not request.config.getvalue("--with-output"):
-        try:
-            shutil.rmtree(str(path))
-        except PermissionError as e:
-            # sporadic error on windows machines...
-            warn(
-                f"Temporary directory could not be removed due to a permissions error: \n{str(e)}"
-            )
-
-
-@pytest.fixture(scope="function")
-def tmp_output_dir_func(tmp_output_dir, request: pytest.FixtureRequest) -> Path:
-    """
-    tmp output dir that gets cleared between every function
-    cleans at the start rather than at cleanup in case the output is to be inspected
-    """
-    subpath = tmp_output_dir / f"__tmpfunc_{request.node.name}__"
-    if subpath.exists():
-        shutil.rmtree(str(subpath))
-    subpath.mkdir()
-    return subpath
-
-
-@pytest.fixture(scope="module")
-def tmp_output_dir_mod(tmp_output_dir, request: pytest.FixtureRequest) -> Path:
-    """
-    tmp output dir that gets cleared between every function
-    cleans at the start rather than at cleanup in case the output is to be inspected
-    """
-    subpath = tmp_output_dir / f"__tmpmod_{request.module}__"
-    if subpath.exists():
-        shutil.rmtree(str(subpath))
-    subpath.mkdir()
-    return subpath
-
-
-@pytest.fixture(scope="function")
-def array_model() -> (
-    Callable[[Tuple[int, ...], Union[Type, np.dtype]], Type[BaseModel]]
-):
-    def _model(
-        shape: Tuple[int, ...] = (10, 10), dtype: Union[Type, np.dtype] = float
-    ) -> Type[BaseModel]:
-        shape_str = ", ".join([str(s) for s in shape])
-
-        class MyModel(BaseModel):
-            array: NDArray[Shape[shape_str], dtype]
-
-        return MyModel
-
-    return _model
-
-
-@pytest.fixture(scope="session")
-def model_rgb() -> Type[BaseModel]:
-    class RGB(BaseModel):
-        array: Optional[
-            Union[
-                NDArray[Shape["* x, * y"], Number],
-                NDArray[Shape["* x, * y, 3 r_g_b"], Number],
-                NDArray[Shape["* x, * y, 3 r_g_b, 4 r_g_b_a"], Number],
-            ]
-        ] = Field(None)
-
-    return RGB
-
-
-@pytest.fixture(scope="session")
-def model_blank() -> Type[BaseModel]:
-    """A model with any shape and dtype"""
-
-    class BlankModel(BaseModel):
-        array: NDArray[Shape["*, ..."], Any]
-
-    return BlankModel
-
-
-@pytest.fixture(scope="function")
-def hdf5_array(
-    request, tmp_output_dir_func
-) -> Callable[[Tuple[int, ...], Union[np.dtype, type]], H5ArrayPath]:
-    hdf5_file = tmp_output_dir_func / "h5f.h5"
-
-    def _hdf5_array(
-        shape: Tuple[int, ...] = (10, 10),
-        dtype: Union[np.dtype, type] = float,
-        compound: bool = False,
-    ) -> H5ArrayPath:
-        array_path = "/" + "_".join([str(s) for s in shape]) + "__" + dtype.__name__
-
-        if not compound:
-            if dtype is str:
-                data = np.random.random(shape).astype(bytes)
-            elif dtype is datetime:
-                data = np.empty(shape, dtype="S32")
-                data.fill(datetime.now(timezone.utc).isoformat().encode("utf-8"))
-            else:
-                data = np.random.random(shape).astype(dtype)
-
-            h5path = H5ArrayPath(hdf5_file, array_path)
-        else:
-            if dtype is str:
-                dt = np.dtype([("data", np.dtype("S10")), ("extra", "i8")])
-                data = np.array([("hey", 0)] * np.prod(shape), dtype=dt).reshape(shape)
-            elif dtype is datetime:
-                dt = np.dtype([("data", np.dtype("S32")), ("extra", "i8")])
-                data = np.array(
-                    [(datetime.now(timezone.utc).isoformat().encode("utf-8"), 0)]
-                    * np.prod(shape),
-                    dtype=dt,
-                ).reshape(shape)
-            else:
-                dt = np.dtype([("data", dtype), ("extra", "i8")])
-                data = np.zeros(shape, dtype=dt)
-            h5path = H5ArrayPath(hdf5_file, array_path, "data")
-
-        with h5py.File(hdf5_file, "w") as h5f:
-            _ = h5f.create_dataset(array_path, data=data)
-        return h5path
-
-    return _hdf5_array
-
-
-@pytest.fixture(scope="function")
-def zarr_nested_array(tmp_output_dir_func) -> ZarrArrayPath:
-    """Zarr array within a nested array"""
-    file = tmp_output_dir_func / "nested.zarr"
-    path = "a/b/c"
-    root = zarr.open(str(file), mode="w")
-    array = root.zeros(path, shape=(100, 100), chunks=(10, 10))
-    return ZarrArrayPath(file=file, path=path)
-
-
-@pytest.fixture(scope="function")
-def zarr_array(tmp_output_dir_func) -> Path:
-    file = tmp_output_dir_func / "array.zarr"
-    array = zarr.open(str(file), mode="w", shape=(100, 100), chunks=(10, 10))
-    array[:] = 0
-    return file
-
-
-@pytest.fixture(scope="function")
-def avi_video(tmp_output_dir_func) -> Callable[[Tuple[int, int], int, bool], Path]:
-    video_path = tmp_output_dir_func / "test.avi"
-
-    def _make_video(shape=(100, 50), frames=10, is_color=True) -> Path:
-        writer = cv2.VideoWriter(
-            str(video_path),
-            cv2.VideoWriter_fourcc(*"RGBA"),  # raw video for testing purposes
-            30,
-            (shape[1], shape[0]),
-            is_color,
-        )
-        if is_color:
-            shape = (*shape, 3)
-
-        for i in range(frames):
-            # make fresh array every time bc opencv eats them
-            array = np.zeros(shape, dtype=np.uint8)
-            if not is_color:
-                array[i, i] = i
-            else:
-                array[i, i, :] = i
-            writer.write(array)
-        writer.release()
-        return video_path
-
-    return _make_video

tests/fixtures/__init__.py

@@ -0,0 +1,3 @@
+from .generation import *
+from .models import *
+from .paths import *

tests/fixtures/generation.py

@@ -0,0 +1,63 @@
+from pathlib import Path
+from typing import Callable, Tuple, Union
+
+import numpy as np
+import pytest
+import zarr
+
+from numpydantic.interface.hdf5 import H5ArrayPath
+from numpydantic.interface.zarr import ZarrArrayPath
+from numpydantic.testing.interfaces import HDF5Case, HDF5CompoundCase, VideoCase
+
+
+@pytest.fixture(scope="function")
+def hdf5_array(
+    request, tmp_output_dir_func
+) -> Callable[[Tuple[int, ...], Union[np.dtype, type]], H5ArrayPath]:
+
+    def _hdf5_array(
+        shape: Tuple[int, ...] = (10, 10),
+        dtype: Union[np.dtype, type] = float,
+        compound: bool = False,
+    ) -> H5ArrayPath:
+        if compound:
+            array: H5ArrayPath = HDF5CompoundCase.make_array(
+                shape, dtype, tmp_output_dir_func
+            )
+            return array
+        else:
+            return HDF5Case.make_array(shape, dtype, tmp_output_dir_func)
+
+    return _hdf5_array
+
+
+@pytest.fixture(scope="function")
+def zarr_nested_array(tmp_output_dir_func) -> ZarrArrayPath:
+    """Zarr array within a nested array"""
+    file = tmp_output_dir_func / "nested.zarr"
+    path = "a/b/c"
+    root = zarr.open(str(file), mode="w")
+    _ = root.zeros(path, shape=(100, 100), chunks=(10, 10))
+    return ZarrArrayPath(file=file, path=path)
+
+
+@pytest.fixture(scope="function")
+def zarr_array(tmp_output_dir_func) -> Path:
+    file = tmp_output_dir_func / "array.zarr"
+    array = zarr.open(str(file), mode="w", shape=(100, 100), chunks=(10, 10))
+    array[:] = 0
+    return file
+
+
+@pytest.fixture(scope="function")
+def avi_video(tmp_output_dir_func) -> Callable[[Tuple[int, int], int, bool], Path]:
+
+    def _make_video(shape=(100, 50), frames=10, is_color=True) -> Path:
+        shape = (frames, *shape)
+        if is_color:
+            shape = (*shape, 3)
+        return VideoCase.make_array(
+            shape=shape, dtype=np.uint8, path=tmp_output_dir_func
+        )
+
+    return _make_video

tests/fixtures/models.py

@@ -0,0 +1,49 @@
+from typing import Any, Callable, Optional, Tuple, Type, Union
+
+import numpy as np
+import pytest
+from pydantic import BaseModel, Field
+
+from numpydantic import NDArray, Shape
+from numpydantic.dtype import Number
+
+
+@pytest.fixture(scope="function")
+def array_model() -> (
+    Callable[[Tuple[int, ...], Union[Type, np.dtype]], Type[BaseModel]]
+):
+    def _model(
+        shape: Tuple[int, ...] = (10, 10), dtype: Union[Type, np.dtype] = float
+    ) -> Type[BaseModel]:
+        shape_str = ", ".join([str(s) for s in shape])
+
+        class MyModel(BaseModel):
+            array: NDArray[Shape[shape_str], dtype]
+
+        return MyModel
+
+    return _model
+
+
+@pytest.fixture(scope="session")
+def model_rgb() -> Type[BaseModel]:
+    class RGB(BaseModel):
+        array: Optional[
+            Union[
+                NDArray[Shape["* x, * y"], Number],
+                NDArray[Shape["* x, * y, 3 r_g_b"], Number],
+                NDArray[Shape["* x, * y, 3 r_g_b, 4 r_g_b_a"], Number],
+            ]
+        ] = Field(None)
+
+    return RGB
+
+
+@pytest.fixture(scope="session")
+def model_blank() -> Type[BaseModel]:
+    """A model with any shape and dtype"""
+
+    class BlankModel(BaseModel):
+        array: NDArray[Shape["*, ..."], Any]
+
+    return BlankModel

tests/fixtures/paths.py

@@ -0,0 +1,51 @@
+import shutil
+from _warnings import warn
+from pathlib import Path
+
+import pytest
+
+
+@pytest.fixture(scope="session")
+def tmp_output_dir(request: pytest.FixtureRequest) -> Path:
+    path = Path(__file__).parents[1].resolve() / "__tmp__"
+    if path.exists():
+        shutil.rmtree(str(path))
+    path.mkdir()
+
+    yield path
+
+    if not request.config.getvalue("--with-output"):
+        try:
+            shutil.rmtree(str(path))
+        except PermissionError as e:
+            # sporadic error on windows machines...
+            warn(
+                "Temporary directory could not be removed due to a permissions error: "
+                f"\n{str(e)}"
+            )
+
+
+@pytest.fixture(scope="function")
+def tmp_output_dir_func(tmp_output_dir, request: pytest.FixtureRequest) -> Path:
+    """
+    tmp output dir that gets cleared between every function
+    cleans at the start rather than at cleanup in case the output is to be inspected
+    """
+    subpath = tmp_output_dir / f"__tmpfunc_{request.node.name}__"
+    if subpath.exists():
+        shutil.rmtree(str(subpath))
+    subpath.mkdir()
+    return subpath
+
+
+@pytest.fixture(scope="module")
+def tmp_output_dir_mod(tmp_output_dir, request: pytest.FixtureRequest) -> Path:
+    """
+    tmp output dir that gets cleared between every function
+    cleans at the start rather than at cleanup in case the output is to be inspected
+    """
+    subpath = tmp_output_dir / f"__tmpmod_{request.module}__"
+    if subpath.exists():
+        shutil.rmtree(str(subpath))
+    subpath.mkdir()
+    return subpath

tests/test_interface/conftest.py

@@ -1,80 +1,150 @@
 import pytest
 
-from typing import Callable, Tuple, Type
+from numpydantic.testing.cases import (
-import numpy as np
+    ALL_CASES,
-import dask.array as da
+    ALL_CASES_PASSING,
-import zarr
+    DTYPE_AND_INTERFACE_CASES_PASSING,
-from pydantic import BaseModel
+)
-
+from numpydantic.testing.helpers import InterfaceCase, ValidationCase, merge_cases
-from numpydantic import interface, NDArray
+from numpydantic.testing.interfaces import (
+    DaskCase,
+    HDF5Case,
+    NumpyCase,
+    VideoCase,
+    ZarrCase,
+    ZarrDirCase,
+    ZarrNestedCase,
+)
 
 
 @pytest.fixture(
     scope="function",
     params=[
         pytest.param(
-            ([[1, 2], [3, 4]], interface.NumpyInterface),
+            NumpyCase,
-            marks=pytest.mark.numpy,
-            id="numpy-list",
-        ),
-        pytest.param(
-            (np.zeros((3, 4)), interface.NumpyInterface),
             marks=pytest.mark.numpy,
             id="numpy",
         ),
         pytest.param(
-            ("hdf5_array", interface.H5Interface),
+            HDF5Case,
             marks=pytest.mark.hdf5,
             id="h5-array-path",
         ),
         pytest.param(
-            (da.random.random((10, 10)), interface.DaskInterface),
+            DaskCase,
             marks=pytest.mark.dask,
             id="dask",
         ),
         pytest.param(
-            (zarr.ones((10, 10)), interface.ZarrInterface),
+            ZarrCase,
             marks=pytest.mark.zarr,
             id="zarr-memory",
         ),
         pytest.param(
-            ("zarr_nested_array", interface.ZarrInterface),
+            ZarrNestedCase,
             marks=pytest.mark.zarr,
             id="zarr-nested",
         ),
         pytest.param(
-            ("zarr_array", interface.ZarrInterface),
+            ZarrDirCase,
             marks=pytest.mark.zarr,
-            id="zarr-array",
+            id="zarr-dir",
-        ),
-        pytest.param(
-            ("avi_video", interface.VideoInterface), marks=pytest.mark.video, id="video"
         ),
+        pytest.param(VideoCase, marks=pytest.mark.video, id="video"),
     ],
 )
-def interface_type(request) -> Tuple[NDArray, Type[interface.Interface]]:
+def interface_cases(request) -> InterfaceCase:
     """
-    Test cases for each interface's ``check`` method - each input should match the
+    Fixture for combinatoric tests across all interface cases
-    provided interface and that interface only
+    """
+    return request.param
+
+
+@pytest.fixture(
+    params=(
+        pytest.param(p, id=p.id, marks=getattr(pytest.mark, p.interface.interface.name))
+        for p in ALL_CASES
+    )
+)
+def all_cases(interface_cases, request) -> ValidationCase:
+    """
+    Combinatoric testing for all dtype, shape, and interface cases.
+
+    This is a very expensive fixture! Only use it for core functionality
+    that we want to be sure is *very true* in every circumstance,
+    INCLUDING invalid combinations of annotations and arrays.
+    Typically, that means only use this in `test_interfaces.py`
+    """
+
+    case = merge_cases(request.param, ValidationCase(interface=interface_cases))
+    if case.skip():
+        pytest.skip()
+    return case
+
+
+@pytest.fixture(
+    params=(
+        pytest.param(p, id=p.id, marks=getattr(pytest.mark, p.interface.interface.name))
+        for p in ALL_CASES_PASSING
+    )
+)
+def all_passing_cases(request) -> ValidationCase:
+    """
+    Combinatoric testing for all dtype, shape, and interface cases,
+    but only the combinations that we expect to pass.
+
+    This is a very expensive fixture! Only use it for core functionality
+    that we want to be sure is *very true* in every circumstance.
+    Typically, that means only use this in `test_interfaces.py`
     """
-    if isinstance(request.param[0], str):
-        return (request.getfixturevalue(request.param[0]), request.param[1])
-    else:
     return request.param
 
 
 @pytest.fixture()
-def all_interfaces(interface_type) -> BaseModel:
+def all_cases_instance(all_cases, tmp_output_dir_func):
     """
-    An instantiated version of each interface within a basemodel,
+    all_cases but with an instantiated model
-    with the array in an `array` field
+    Args:
+        all_cases:
+
+    Returns:
+
     """
-    array, interface = interface_type
+    array = all_cases.array(path=tmp_output_dir_func)
-    if isinstance(array, Callable):
+    instance = all_cases.model(array=array)
-        array = array()
+    return instance
-
+
-    class MyModel(BaseModel):
+
-        array: NDArray
+@pytest.fixture()
-
+def all_passing_cases_instance(all_passing_cases, tmp_output_dir_func):
-    instance = MyModel(array=array)
+    """
+    all_cases but with an instantiated model
+    Args:
+        all_cases:
+
+    Returns:
+
+    """
+    array = all_passing_cases.array(path=tmp_output_dir_func)
+    instance = all_passing_cases.model(array=array)
+    return instance
+
+
+@pytest.fixture(
+    params=(
+        pytest.param(p, id=p.id, marks=getattr(pytest.mark, p.interface.interface.name))
+        for p in DTYPE_AND_INTERFACE_CASES_PASSING
+    )
+)
+def dtype_by_interface(request):
+    """
+    Tests for all dtypes by all interfaces
+    """
+    return request.param
+
+
+@pytest.fixture()
+def dtype_by_interface_instance(dtype_by_interface, tmp_output_dir_func):
+    array = dtype_by_interface.array(path=tmp_output_dir_func)
+    instance = dtype_by_interface.model(array=array)
     return instance

tests/test_interface/test_dask.py

@@ -1,33 +1,14 @@
-import pytest
 import json
 
 import dask.array as da
-from pydantic import BaseModel, ValidationError
+import pytest
 
 from numpydantic.interface import DaskInterface
-from numpydantic.exceptions import DtypeError, ShapeError
+from numpydantic.testing.interfaces import DaskCase
-
-from tests.conftest import ValidationCase
 
 pytestmark = pytest.mark.dask
 
 
-def dask_array(case: ValidationCase) -> da.Array:
-    if issubclass(case.dtype, BaseModel):
-        return da.full(shape=case.shape, fill_value=case.dtype(x=1), chunks=-1)
-    else:
-        return da.zeros(shape=case.shape, dtype=case.dtype, chunks=10)
-
-
-def _test_dask_case(case: ValidationCase):
-    array = dask_array(case)
-    if case.passes:
-        case.model(array=array)
-    else:
-        with pytest.raises((ValidationError, DtypeError, ShapeError)):
-            case.model(array=array)
-
-
 def test_dask_enabled():
     """
     We need dask to be available to run these tests :)
@@ -35,21 +16,25 @@ def test_dask_enabled():
     assert DaskInterface.enabled()
 
 
-def test_dask_check(interface_type):
+def test_dask_check(interface_cases, tmp_output_dir_func):
-    if interface_type[1] is DaskInterface:
+    array = interface_cases.make_array(path=tmp_output_dir_func)
-        assert DaskInterface.check(interface_type[0])
+
+    if interface_cases.interface is DaskInterface:
+        assert DaskInterface.check(array)
     else:
-        assert not DaskInterface.check(interface_type[0])
+        assert not DaskInterface.check(array)
 
 
 @pytest.mark.shape
 def test_dask_shape(shape_cases):
-    _test_dask_case(shape_cases)
+    shape_cases.interface = DaskCase
+    shape_cases.validate_case()
 
 
 @pytest.mark.dtype
 def test_dask_dtype(dtype_cases):
-    _test_dask_case(dtype_cases)
+    dtype_cases.interface = DaskCase
+    dtype_cases.validate_case()
 
 
 @pytest.mark.serialization

tests/test_interface/test_hdf5.py

@@ -1,61 +1,54 @@
 import json
-from datetime import datetime, timezone
+from datetime import datetime
 from typing import Any
 
 import h5py
-import pytest
-from pydantic import BaseModel, ValidationError
-
 import numpy as np
+import pytest
+from pydantic import BaseModel
+
 from numpydantic import NDArray, Shape
 from numpydantic.interface import H5Interface
 from numpydantic.interface.hdf5 import H5ArrayPath, H5Proxy
-from numpydantic.exceptions import DtypeError, ShapeError
+from numpydantic.testing.interfaces import HDF5Case, HDF5CompoundCase
-
-from tests.conftest import ValidationCase
 
 pytestmark = pytest.mark.hdf5
 
 
-def hdf5_array_case(
+@pytest.fixture(
-    case: ValidationCase, array_func, compound: bool = False
+    params=[
-) -> H5ArrayPath:
+        pytest.param(HDF5Case, id="hdf5"),
-    """
+        pytest.param(HDF5CompoundCase, id="hdf5-compound"),
-    Args:
+    ]
-        case:
+)
-        array_func: ( the function returned from the `hdf5_array` fixture )
+def hdf5_cases(request):
-
+    return request.param
-    Returns:
-
-    """
-    if issubclass(case.dtype, BaseModel):
-        pytest.skip("hdf5 cant support arbitrary python objects")
-    return array_func(case.shape, case.dtype, compound)
-
-
-def _test_hdf5_case(case: ValidationCase, array_func, compound: bool = False) -> None:
-    array = hdf5_array_case(case, array_func, compound)
-    if case.passes:
-        case.model(array=array)
-    else:
-        with pytest.raises((ValidationError, DtypeError, ShapeError)):
-            case.model(array=array)
 
 
 def test_hdf5_enabled():
     assert H5Interface.enabled()
 
 
-def test_hdf5_check(interface_type):
+@pytest.mark.shape
-    if interface_type[1] is H5Interface:
+def test_hdf5_shape(shape_cases, hdf5_cases):
-        if interface_type[0].__name__ == "_hdf5_array":
+    shape_cases.interface = hdf5_cases
-            interface_type = (interface_type[0](), interface_type[1])
+    if shape_cases.skip():
-        assert H5Interface.check(interface_type[0])
+        pytest.skip()
-        if isinstance(interface_type[0], H5ArrayPath):
+    shape_cases.validate_case()
-            # also test that we can instantiate from a tuple like the H5ArrayPath
+
-            assert H5Interface.check((interface_type[0].file, interface_type[0].path))
+
+@pytest.mark.dtype
+def test_hdf5_dtype(dtype_cases, hdf5_cases):
+    dtype_cases.interface = hdf5_cases
+    dtype_cases.validate_case()
+
+
+def test_hdf5_check(interface_cases, tmp_output_dir_func):
+    array = interface_cases.make_array(path=tmp_output_dir_func)
+    if interface_cases.interface is H5Interface:
+        assert H5Interface.check(array)
     else:
-        assert not H5Interface.check(interface_type[0])
+        assert not H5Interface.check(array)
 
 
 def test_hdf5_check_not_exists():
@@ -74,18 +67,6 @@ def test_hdf5_check_not_hdf5(tmp_path):
     assert not H5Interface.check(spec)
 
 
-@pytest.mark.shape
-@pytest.mark.parametrize("compound", [True, False])
-def test_hdf5_shape(shape_cases, hdf5_array, compound):
-    _test_hdf5_case(shape_cases, hdf5_array, compound)
-
-
-@pytest.mark.dtype
-@pytest.mark.parametrize("compound", [True, False])
-def test_hdf5_dtype(dtype_cases, hdf5_array, compound):
-    _test_hdf5_case(dtype_cases, hdf5_array, compound)
-
-
 def test_hdf5_dataset_not_exists(hdf5_array, model_blank):
     array = hdf5_array()
     with pytest.raises(ValueError) as e:
@@ -221,10 +202,7 @@ def test_empty_dataset(dtype, tmp_path):
     Empty datasets shouldn't choke us during validation
     """
     array_path = tmp_path / "test.h5"
-    if dtype in (str, datetime):
+    np_dtype = "S32" if dtype in (str, datetime) else dtype
-        np_dtype = "S32"
-    else:
-        np_dtype = dtype
 
     with h5py.File(array_path, "w") as h5f:
         _ = h5f.create_dataset(name="/data", dtype=np_dtype)

tests/test_interface/test_interface_base.py

@@ -6,18 +6,17 @@ for tests that should apply to all interfaces, use ``test_interfaces.py``
 import gc
 from typing import Literal
 
-import pytest
 import numpy as np
+import pytest
+from pydantic import ValidationError
 
 from numpydantic.interface import (
     Interface,
-    JsonDict,
     InterfaceMark,
-    NumpyInterface,
+    JsonDict,
     MarkedJson,
+    NumpyInterface,
 )
-from pydantic import ValidationError
-
 from numpydantic.interface.interface import V
 
 
@@ -46,9 +45,7 @@ def interfaces():
         @classmethod
         def check(cls, array):
             cls.checked = True
-            if isinstance(array, list):
+            return isinstance(array, list)
-                return True
-            return False
 
         @classmethod
         def enabled(cls) -> bool:
@@ -94,7 +91,8 @@ def interfaces():
 
 def test_interface_match_error(interfaces):
     """
-    Test that `match` and `match_output` raises errors when no or multiple matches are found
+    Test that `match` and `match_output` raises errors when no or multiple matches
+    are found
     """
     with pytest.raises(ValueError) as e:
         Interface.match([1, 2, 3])

tests/test_interface/test_interfaces.py

@@ -2,87 +2,108 @@
 Tests that should be applied to all interfaces
 """
 
-import pytest
-from typing import Callable
-from importlib.metadata import version
 import json
+from importlib.metadata import version
 
-import numpy as np
 import dask.array as da
-from zarr.core import Array as ZarrArray
+import numpy as np
+import pytest
 from pydantic import BaseModel
+from zarr.core import Array as ZarrArray
 
 from numpydantic.interface import Interface, InterfaceMark, MarkedJson
+from numpydantic.testing.helpers import ValidationCase
 
 
-def _test_roundtrip(source: BaseModel, target: BaseModel, round_trip: bool):
+def _test_roundtrip(source: BaseModel, target: BaseModel):
     """Test model equality for roundtrip tests"""
-    if round_trip:
+
     assert type(target.array) is type(source.array)
     if isinstance(source.array, (np.ndarray, ZarrArray)):
         assert np.array_equal(target.array, np.array(source.array))
     elif isinstance(source.array, da.Array):
+        if target.array.dtype == object:
+            # object equality doesn't really work well with dask
+            # just check that the types match
+            target_type = type(target.array.ravel()[0].compute())
+            source_type = type(source.array.ravel()[0].compute())
+            assert target_type is source_type
+        else:
             assert np.all(da.equal(target.array, source.array))
     else:
         assert target.array == source.array
 
     assert target.array.dtype == source.array.dtype
-    else:
-        assert np.array_equal(target.array, np.array(source.array))
 
 
-def test_dunder_len(all_interfaces):
+def test_dunder_len(interface_cases, tmp_output_dir_func):
     """
     Each interface or proxy type should support __len__
     """
-    assert len(all_interfaces.array) == all_interfaces.array.shape[0]
+    case = ValidationCase(interface=interface_cases)
+    if interface_cases.interface.name == "video":
+        case.shape = (10, 10, 2, 3)
+        case.dtype = np.uint8
+        case.annotation_dtype = np.uint8
+        case.annotation_shape = (10, 10, "*", 3)
+    array = case.array(path=tmp_output_dir_func)
+    instance = case.model(array=array)
+    assert len(instance.array) == case.shape[0]
 
 
-def test_interface_revalidate(all_interfaces):
+def test_interface_revalidate(all_passing_cases_instance):
     """
     An interface should revalidate with the output of its initial validation
 
     See: https://github.com/p2p-ld/numpydantic/pull/14
     """
-    _ = type(all_interfaces)(array=all_interfaces.array)
+
+    _ = type(all_passing_cases_instance)(array=all_passing_cases_instance.array)
 
 
-def test_interface_rematch(interface_type):
+@pytest.mark.xfail
+def test_interface_rematch(interface_cases, tmp_output_dir_func):
     """
     All interfaces should match the results of the object they return after validation
     """
-    array, interface = interface_type
+    array = interface_cases.make_array(path=tmp_output_dir_func)
-    if isinstance(array, Callable):
-        array = array()
 
-    assert Interface.match(interface().validate(array)) is interface
+    assert (
+        Interface.match(interface_cases.interface.validate(array))
+        is interface_cases.interface
+    )
 
 
-def test_interface_to_numpy_array(all_interfaces):
+def test_interface_to_numpy_array(dtype_by_interface_instance):
     """
     All interfaces should be able to have the output of their validation stage
     coerced to a numpy array with np.array()
     """
-    _ = np.array(all_interfaces.array)
+    _ = np.array(dtype_by_interface_instance.array)
 
 
 @pytest.mark.serialization
-def test_interface_dump_json(all_interfaces):
+def test_interface_dump_json(dtype_by_interface_instance):
     """
     All interfaces should be able to dump to json
     """
-    all_interfaces.model_dump_json()
+    dtype_by_interface_instance.model_dump_json()
 
 
 @pytest.mark.serialization
-@pytest.mark.parametrize("round_trip", [True, False])
+def test_interface_roundtrip_json(dtype_by_interface, tmp_output_dir_func):
-def test_interface_roundtrip_json(all_interfaces, round_trip):
     """
     All interfaces should be able to roundtrip to and from json
     """
-    dumped_json = all_interfaces.model_dump_json(round_trip=round_trip)
+    if "subclass" in dtype_by_interface.id.lower():
-    model = all_interfaces.model_validate_json(dumped_json)
+        pytest.xfail()
-    _test_roundtrip(all_interfaces, model, round_trip)
+
+    array = dtype_by_interface.array(path=tmp_output_dir_func)
+    case = dtype_by_interface.model(array=array)
+
+    dumped_json = case.model_dump_json(round_trip=True)
+    model = case.model_validate_json(dumped_json)
+    _test_roundtrip(case, model)
 
 
 @pytest.mark.serialization
@@ -101,15 +122,20 @@ def test_interface_mark_interface(an_interface):
 
 @pytest.mark.serialization
 @pytest.mark.parametrize("valid", [True, False])
-@pytest.mark.parametrize("round_trip", [True, False])
 @pytest.mark.filterwarnings("ignore:Mismatch between serialized mark")
-def test_interface_mark_roundtrip(all_interfaces, valid, round_trip):
+def test_interface_mark_roundtrip(dtype_by_interface, valid, tmp_output_dir_func):
     """
     All interfaces should be able to roundtrip with the marked interface,
     and a mismatch should raise a warning and attempt to proceed
     """
-    dumped_json = all_interfaces.model_dump_json(
+    if "subclass" in dtype_by_interface.id.lower():
-        round_trip=round_trip, context={"mark_interface": True}
+        pytest.xfail()
+
+    array = dtype_by_interface.array(path=tmp_output_dir_func)
+    case = dtype_by_interface.model(array=array)
+
+    dumped_json = case.model_dump_json(
+        round_trip=True, context={"mark_interface": True}
     )
 
     data = json.loads(dumped_json)
@@ -123,8 +149,8 @@ def test_interface_mark_roundtrip(all_interfaces, valid, round_trip):
         dumped_json = json.dumps(data)
 
         with pytest.warns(match="Mismatch.*"):
-            model = all_interfaces.model_validate_json(dumped_json)
+            model = case.model_validate_json(dumped_json)
     else:
-        model = all_interfaces.model_validate_json(dumped_json)
+        model = case.model_validate_json(dumped_json)
 
-    _test_roundtrip(all_interfaces, model, round_trip)
+    _test_roundtrip(case, model)

tests/test_interface/test_numpy.py

@@ -1,37 +1,21 @@
 import numpy as np
 import pytest
-from pydantic import ValidationError, BaseModel
-from numpydantic.exceptions import DtypeError, ShapeError
 
-from tests.conftest import ValidationCase
+from numpydantic.testing.cases import NumpyCase
 
 pytestmark = pytest.mark.numpy
 
 
-def numpy_array(case: ValidationCase) -> np.ndarray:
-    if issubclass(case.dtype, BaseModel):
-        return np.full(shape=case.shape, fill_value=case.dtype(x=1))
-    else:
-        return np.zeros(shape=case.shape, dtype=case.dtype)
-
-
-def _test_np_case(case: ValidationCase):
-    array = numpy_array(case)
-    if case.passes:
-        case.model(array=array)
-    else:
-        with pytest.raises((ValidationError, DtypeError, ShapeError)):
-            case.model(array=array)
-
-
 @pytest.mark.shape
 def test_numpy_shape(shape_cases):
-    _test_np_case(shape_cases)
+    shape_cases.interface = NumpyCase
+    shape_cases.validate_case()
 
 
 @pytest.mark.dtype
 def test_numpy_dtype(dtype_cases):
-    _test_np_case(dtype_cases)
+    dtype_cases.interface = NumpyCase
+    dtype_cases.validate_case()
 
 
 def test_numpy_coercion(model_blank):

tests/test_interface/test_video.py

@@ -2,12 +2,10 @@
 Needs to be refactored to DRY, but works for now
 """
 
-import numpy as np
-import pytest
-
 from pathlib import Path
-import cv2
 
+import cv2
+import pytest
 from pydantic import BaseModel, ValidationError
 
 from numpydantic import NDArray, Shape
@@ -65,7 +63,7 @@ def test_video_wrong_shape(avi_video):
 
     # should correctly validate :)
     with pytest.raises(ValidationError):
-        instance = MyModel(array=vid)
+        _ = MyModel(array=vid)
 
 
 @pytest.mark.proxy
@@ -82,15 +80,12 @@ def test_video_getitem(avi_video):
 
     instance = MyModel(array=vid)
     fifth_frame = instance.array[5]
-    # the first frame should have 1's in the 1,1 position
+    # the fifth frame should be all 5s
     assert (fifth_frame[5, 5, :] == [5, 5, 5]).all()
-    # and nothing in the 6th position
-    assert (fifth_frame[6, 6, :] == [0, 0, 0]).all()
 
     # slicing should also work as if it were just a numpy array
     single_slice = instance.array[3, 0:10, 0:5]
     assert single_slice[3, 3, 0] == 3
-    assert single_slice[4, 4, 0] == 0
     assert single_slice.shape == (10, 5, 3)
 
     # also get a range of frames
@@ -98,19 +93,19 @@ def test_video_getitem(avi_video):
     range_slice = instance.array[3:5]
     assert range_slice.shape == (2, 100, 50, 3)
     assert range_slice[0, 3, 3, 0] == 3
-    assert range_slice[0, 4, 4, 0] == 0
+    assert range_slice[1, 4, 4, 0] == 4
 
     # full range
     range_slice = instance.array[3:5, 0:10, 0:5]
     assert range_slice.shape == (2, 10, 5, 3)
     assert range_slice[0, 3, 3, 0] == 3
-    assert range_slice[0, 4, 4, 0] == 0
+    assert range_slice[1, 4, 4, 0] == 4
 
     # starting range
     range_slice = instance.array[6:, 0:10, 0:10]
     assert range_slice.shape == (4, 10, 10, 3)
     assert range_slice[-1, 9, 9, 0] == 9
-    assert range_slice[-2, 9, 9, 0] == 0
+    assert range_slice[-2, 9, 9, 0] == 8
 
     # ending range
     range_slice = instance.array[:3, 0:5, 0:5]
@@ -121,10 +116,8 @@ def test_video_getitem(avi_video):
     # second slice should be the second frame (instead of the first)
     assert range_slice.shape == (3, 6, 6, 3)
     assert range_slice[1, 2, 2, 0] == 2
-    assert range_slice[1, 3, 3, 0] == 0
     # and the third should be the fourth (instead of the second)
     assert range_slice[2, 4, 4, 0] == 4
-    assert range_slice[2, 5, 5, 0] == 0
 
     with pytest.raises(NotImplementedError):
         # shouldn't be allowed to set

tests/test_interface/test_zarr.py

@@ -1,61 +1,21 @@
 import json
 
+import numpy as np
 import pytest
-import zarr
-
-from pydantic import BaseModel, ValidationError
-from numcodecs import Pickle
 
 from numpydantic.interface import ZarrInterface
 from numpydantic.interface.zarr import ZarrArrayPath
-from numpydantic.exceptions import DtypeError, ShapeError
+from numpydantic.testing.cases import ZarrCase, ZarrDirCase, ZarrNestedCase, ZarrZipCase
-
+from numpydantic.testing.helpers import InterfaceCase
-from tests.conftest import ValidationCase
 
 pytestmark = pytest.mark.zarr
 
 
-@pytest.fixture()
+@pytest.fixture(
-def dir_array(tmp_output_dir_func) -> zarr.DirectoryStore:
+    params=[ZarrCase, ZarrZipCase, ZarrDirCase, ZarrNestedCase],
-    store = zarr.DirectoryStore(tmp_output_dir_func / "array.zarr")
+)
-    return store
+def zarr_case(request) -> InterfaceCase:
-
+    return request.param
-
-@pytest.fixture()
-def zip_array(tmp_output_dir_func) -> zarr.ZipStore:
-    store = zarr.ZipStore(tmp_output_dir_func / "array.zip", mode="w")
-    return store
-
-
-@pytest.fixture()
-def nested_dir_array(tmp_output_dir_func) -> zarr.NestedDirectoryStore:
-    store = zarr.NestedDirectoryStore(tmp_output_dir_func / "nested")
-    return store
-
-
-def _zarr_array(case: ValidationCase, store) -> zarr.core.Array:
-    if issubclass(case.dtype, BaseModel):
-        pytest.skip(
-            f"Zarr can't handle objects properly at the moment, "
-            "see https://github.com/zarr-developers/zarr-python/issues/2081"
-        )
-        # return zarr.full(
-        #     shape=case.shape,
-        #     fill_value=case.dtype(x=1),
-        #     dtype=object,
-        #     object_codec=Pickle(),
-        # )
-    else:
-        return zarr.zeros(shape=case.shape, dtype=case.dtype, store=store)
-
-
-def _test_zarr_case(case: ValidationCase, store):
-    array = _zarr_array(case, store)
-    if case.passes:
-        case.model(array=array)
-    else:
-        with pytest.raises((ValidationError, DtypeError, ShapeError)):
-            case.model(array=array)
 
 
 @pytest.fixture(
@@ -78,24 +38,29 @@ def test_zarr_enabled():
     assert ZarrInterface.enabled()
 
 
-def test_zarr_check(interface_type):
+def test_zarr_check(interface_cases, tmp_output_dir_func):
     """
     We should only use the zarr interface for zarr-like things
     """
-    if interface_type[1] is ZarrInterface:
+    array = interface_cases.make_array(path=tmp_output_dir_func)
-        assert ZarrInterface.check(interface_type[0])
+    if interface_cases.interface is ZarrInterface:
+        assert ZarrInterface.check(array)
     else:
-        assert not ZarrInterface.check(interface_type[0])
+        assert not ZarrInterface.check(array)
 
 
 @pytest.mark.shape
-def test_zarr_shape(store, shape_cases):
+def test_zarr_shape(shape_cases, zarr_case):
-    _test_zarr_case(shape_cases, store)
+    shape_cases.interface = zarr_case
+    shape_cases.validate_case()
 
 
 @pytest.mark.dtype
-def test_zarr_dtype(dtype_cases, store):
+def test_zarr_dtype(dtype_cases, zarr_case):
-    _test_zarr_case(dtype_cases, store)
+    dtype_cases.interface = zarr_case
+    if dtype_cases.skip():
+        pytest.skip()
+    dtype_cases.validate_case()
 
 
 @pytest.mark.parametrize("array", ["zarr_nested_array", "zarr_array"])
@@ -103,14 +68,14 @@ def test_zarr_from_tuple(array, model_blank, request):
     """Should be able to do the same validation logic from tuples as an input"""
     array = request.getfixturevalue(array)
     if isinstance(array, ZarrArrayPath):
-        instance = model_blank(array=(array.file, array.path))
+        _ = model_blank(array=(array.file, array.path))
     else:
-        instance = model_blank(array=(array,))
+        _ = model_blank(array=(array,))
 
 
 def test_zarr_from_path(zarr_array, model_blank):
     """Should be able to just pass a path"""
-    instance = model_blank(array=zarr_array)
+    _ = model_blank(array=zarr_array)
 
 
 def test_zarr_array_path_from_iterable(zarr_array):
@@ -129,7 +94,7 @@ def test_zarr_array_path_from_iterable(zarr_array):
 @pytest.mark.serialization
 @pytest.mark.parametrize("dump_array", [True, False])
 @pytest.mark.parametrize("roundtrip", [True, False])
-def test_zarr_to_json(store, model_blank, roundtrip, dump_array):
+def test_zarr_to_json(zarr_case, model_blank, roundtrip, dump_array, tmp_path):
     expected_fields = (
         "Type",
         "Data type",
@@ -139,9 +104,9 @@ def test_zarr_to_json(store, model_blank, roundtrip, dump_array):
         "Store type",
         "hexdigest",
     )
-    lol_array = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
+    lol_array = np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9]], dtype=int)
 
-    array = zarr.array(lol_array, store=store)
+    array = zarr_case.make_array(array=lol_array, dtype=int, path=tmp_path)
     instance = model_blank(array=array)
 
     context = {"dump_array": dump_array}
@@ -151,7 +116,7 @@ def test_zarr_to_json(store, model_blank, roundtrip, dump_array):
 
     if roundtrip:
         if dump_array:
-            assert as_json["value"] == lol_array
+            assert np.array_equal(as_json["value"], lol_array)
         else:
             if as_json.get("file", False):
                 assert "array" not in as_json
@@ -161,4 +126,4 @@ def test_zarr_to_json(store, model_blank, roundtrip, dump_array):
         assert len(as_json["info"]["hexdigest"]) == 40
 
     else:
-        assert as_json == lol_array
+        assert np.array_equal(as_json, lol_array)

tests/test_meta.py

@@ -1,4 +1,5 @@
 import sys
+
 import pytest
 
 from numpydantic import NDArray
@@ -40,4 +41,4 @@ def test_stub_revealed_type():
     """
     Check that the revealed type matches the stub
     """
-    type = reveal_type(NDArray)
+    _ = reveal_type(NDArray)

tests/test_ndarray.py

@@ -1,16 +1,13 @@
-import pytest
-
-from typing import Union, Optional, Any
 import json
+from typing import Any, Optional, Union
 
 import numpy as np
-from pydantic import BaseModel, ValidationError, Field
+import pytest
+from pydantic import BaseModel, Field, ValidationError
 
-
+from numpydantic import NDArray, Shape, dtype
-from numpydantic import NDArray, Shape
-from numpydantic.exceptions import ShapeError, DtypeError
-from numpydantic import dtype
 from numpydantic.dtype import Number
+from numpydantic.exceptions import DtypeError
 
 
 @pytest.mark.json_schema
@@ -28,15 +25,15 @@ def test_ndarray_type():
     assert schema["properties"]["array"]["minItems"] == 2
 
     # models should instantiate correctly!
-    instance = Model(array=np.zeros((2, 3)))
+    _ = Model(array=np.zeros((2, 3)))
 
     with pytest.raises(ValidationError):
-        instance = Model(array=np.zeros((4, 6)))
+        _ = Model(array=np.zeros((4, 6)))
 
     with pytest.raises(ValidationError):
-        instance = Model(array=np.ones((2, 3), dtype=bool))
+        _ = Model(array=np.ones((2, 3), dtype=bool))
 
-    instance = Model(array=np.zeros((2, 3)), array_any=np.ones((3, 4, 5)))
+    _ = Model(array=np.zeros((2, 3)), array_any=np.ones((3, 4, 5)))
 
 
 @pytest.mark.dtype
@@ -93,6 +90,8 @@ def test_schema_number():
 
 
 def test_ndarray_union():
+    generator = np.random.default_rng()
+
     class Model(BaseModel):
         array: Optional[
             Union[
@@ -102,22 +101,22 @@ def test_ndarray_union():
             ]
         ] = Field(None)
 
-    instance = Model()
+    _ = Model()
-    instance = Model(array=np.random.random((5, 10)))
+    _ = Model(array=generator.random((5, 10)))
-    instance = Model(array=np.random.random((5, 10, 3)))
+    _ = Model(array=generator.random((5, 10, 3)))
-    instance = Model(array=np.random.random((5, 10, 3, 4)))
+    _ = Model(array=generator.random((5, 10, 3, 4)))
 
     with pytest.raises(ValidationError):
-        instance = Model(array=np.random.random((5,)))
+        _ = Model(array=generator.random((5,)))
 
     with pytest.raises(ValidationError):
-        instance = Model(array=np.random.random((5, 10, 4)))
+        _ = Model(array=generator.random((5, 10, 4)))
 
     with pytest.raises(ValidationError):
-        instance = Model(array=np.random.random((5, 10, 3, 6)))
+        _ = Model(array=generator.random((5, 10, 3, 6)))
 
     with pytest.raises(ValidationError):
-        instance = Model(array=np.random.random((5, 10, 4, 6)))
+        _ = Model(array=generator.random((5, 10, 4, 6)))
 
 
 @pytest.mark.shape
@@ -127,15 +126,16 @@ def test_ndarray_unparameterized(dtype):
     """
     NDArray without any parameters is any shape, any type
     """
+    generator = np.random.default_rng()
 
     class Model(BaseModel):
         array: NDArray
 
     # not very sophisticated fuzzing of "any shape"
     test_cases = 10
-    for i in range(test_cases):
+    for _ in range(test_cases):
-        n_dimensions = np.random.randint(1, 8)
+        n_dimensions = generator.integers(1, 8)
-        dim_sizes = np.random.randint(1, 7, size=n_dimensions)
+        dim_sizes = generator.integers(1, 7, size=n_dimensions)
         _ = Model(array=np.zeros(dim_sizes, dtype=dtype))
 
 
@@ -144,15 +144,16 @@ def test_ndarray_any():
     """
     using :class:`typing.Any` in for the shape means any shape
     """
+    generator = np.random.default_rng()
 
     class Model(BaseModel):
         array: NDArray[Any, np.uint8]
 
     # not very sophisticated fuzzing of "any shape"
     test_cases = 100
-    for i in range(test_cases):
+    for _ in range(test_cases):
-        n_dimensions = np.random.randint(1, 8)
+        n_dimensions = generator.integers(1, 8)
-        dim_sizes = np.random.randint(1, 16, size=n_dimensions)
+        dim_sizes = generator.integers(1, 16, size=n_dimensions)
         _ = Model(array=np.zeros(dim_sizes, dtype=np.uint8))
 
 
@@ -191,7 +192,7 @@ def test_ndarray_serialize():
     class Model(BaseModel):
         array: NDArray[Any, Number]
 
-    mod = Model(array=np.random.random((3, 3)))
+    mod = Model(array=np.random.default_rng().random((3, 3)))
     mod_str = mod.model_dump_json()
     mod_json = json.loads(mod_str)
     assert isinstance(mod_json["array"], list)

tests/test_serialization.py

@@ -3,14 +3,15 @@ Test serialization-specific functionality that doesn't need to be
 applied across every interface (use test_interface/test_interfaces for that
 """
 
-import h5py
+import json
-import pytest
 from pathlib import Path
 from typing import Callable
-import numpy as np
-import json
 
-from numpydantic.serialization import _walk_and_apply, _relativize_paths, relative_path
+import h5py
+import numpy as np
+import pytest
+
+from numpydantic.serialization import _relativize_paths, _walk_and_apply, relative_path
 
 pytestmark = pytest.mark.serialization
 
@@ -115,7 +116,8 @@ def test_absolute_path(hdf5_at_path, tmp_output_dir, model_blank):
 
 def test_walk_and_apply():
     """
-    Walk and apply should recursively apply a function to everything in a nesty structure
+    Walk and apply should recursively apply a function to everything in a
+    nesty structure
     """
     test = {
         "a": 1,

tests/test_shape.py

@@ -1,9 +1,8 @@
-import pytest
-
 from typing import Any
 
-from pydantic import BaseModel, ValidationError
 import numpy as np
+import pytest
+from pydantic import BaseModel, ValidationError
 
 from numpydantic import NDArray, Shape
 

tests/test_testing_helpers.py

@@ -0,0 +1,60 @@
+"""
+Tests for the testing helpers lmao
+"""
+
+import numpy as np
+import pytest
+from pydantic import BaseModel
+
+from numpydantic import NDArray, Shape
+from numpydantic.testing.cases import INTERFACE_CASES
+from numpydantic.testing.helpers import ValidationCase
+from numpydantic.testing.interfaces import NumpyCase
+
+
+def test_validation_case_merge():
+    case_1 = ValidationCase(id="1", interface=NumpyCase, passes=False)
+    case_2 = ValidationCase(id="2", dtype=str, passes=True)
+    case_3 = ValidationCase(id="3", shape=(1, 2, 3), passes=True)
+
+    merged_simple = case_2.merge(case_3)
+    assert merged_simple.dtype == case_2.dtype
+    assert merged_simple.shape == case_3.shape
+
+    merged_multi = case_1.merge([case_2, case_3])
+    assert merged_multi.dtype == case_2.dtype
+    assert merged_multi.shape == case_3.shape
+    assert merged_multi.interface == case_1.interface
+
+    # passes should be true only if all the cases are
+    assert merged_simple.passes
+    assert not merged_multi.passes
+
+    # ids should merge
+    assert merged_simple.id == "2-3"
+    assert merged_multi.id == "1-2-3"
+
+
+@pytest.mark.parametrize(
+    "interface",
+    [
+        pytest.param(
+            i.interface, marks=getattr(pytest.mark, i.interface.interface.name)
+        )
+        for i in INTERFACE_CASES
+        if i.id not in ("hdf5_compound")
+    ],
+)
+def test_make_array(interface, tmp_output_dir_func):
+    """
+    An interface case can generate an array from params or a given array
+
+    Not testing correctness here, that's what hte rest of the testing does.
+    """
+    arr = np.zeros((10, 10, 2, 3), dtype=np.uint8)
+    arr = interface.make_array(array=arr, dtype=np.uint8, path=tmp_output_dir_func)
+
+    class MyModel(BaseModel):
+        array: NDArray[Shape["10, 10, 2, 3"], np.uint8]
+
+    _ = MyModel(array=arr)