From 90994b1ba143f8c746cf451352c7c851a635ba47 Mon Sep 17 00:00:00 2001
From: sneakers-the-rat <sneakers-the-rat@protonmail.com>
Date: Mon, 12 Aug 2024 21:10:56 -0700
Subject: [PATCH] get inner object from object array to test arbitrary dtype

---
 src/numpydantic/interface/dask.py      |  5 +++++
 src/numpydantic/interface/interface.py | 12 +++++++++++-
 tests/conftest.py                      |  6 ++++++
 3 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/src/numpydantic/interface/dask.py b/src/numpydantic/interface/dask.py
index d334a0b..7719e98 100644
--- a/src/numpydantic/interface/dask.py
+++ b/src/numpydantic/interface/dask.py
@@ -8,6 +8,7 @@ import numpy as np
 from pydantic import SerializationInfo
 
 from numpydantic.interface.interface import Interface
+from numpydantic.types import DtypeType, NDArrayType
 
 try:
     from dask.array.core import Array as DaskArray
@@ -30,6 +31,10 @@ class DaskInterface(Interface):
         """
         return DaskArray is not None and isinstance(array, DaskArray)
 
+    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())
+
     @classmethod
     def enabled(cls) -> bool:
         """check if we successfully imported dask"""
diff --git a/src/numpydantic/interface/interface.py b/src/numpydantic/interface/interface.py
index 832fe83..3030220 100644
--- a/src/numpydantic/interface/interface.py
+++ b/src/numpydantic/interface/interface.py
@@ -101,7 +101,17 @@ class Interface(ABC, Generic[T]):
         """
         Get the dtype from the input array
         """
-        return array.dtype
+        if hasattr(array.dtype, "type") and array.dtype.type is np.object_:
+            return self.get_object_dtype(array)
+        else:
+            return array.dtype
+
+    def get_object_dtype(self, array: NDArrayType) -> DtypeType:
+        """
+        When an array contains an object, get the dtype of the object contained
+        by the array.
+        """
+        return type(array.ravel()[0])
 
     def validate_dtype(self, dtype: DtypeType) -> bool:
         """
diff --git a/tests/conftest.py b/tests/conftest.py
index af3a48e..0655362 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -62,6 +62,10 @@ class BasicModel(BaseModel):
     x: int
 
 
+class BadModel(BaseModel):
+    x: int
+
+
 RGB_UNION: TypeAlias = Union[
     NDArray[Shape["* x, * y"], Number],
     NDArray[Shape["* x, * y, 3 r_g_b"], Number],
@@ -137,6 +141,7 @@ def shape_cases(request) -> ValidationCase:
         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),
     ],
     ids=[
@@ -162,6 +167,7 @@ def shape_cases(request) -> ValidationCase:
         "str-int",
         "str-float",
         "model-model",
+        "model-badmodel",
         "model-int",
     ],
 )