BUG: Fix assert_frame_equal with check_dtype=False for pd.NA with different dtypes

Author: 0x3vAD

doc/source/whatsnew/v3.0.0.rst

@@ -994,6 +994,7 @@ Other
 - Bug in printing a :class:`Series` with a :class:`DataFrame` stored in :attr:`Series.attrs` raised a ``ValueError`` (:issue:`60568`)
 - Fixed bug where the :class:`DataFrame` constructor misclassified array-like objects with a ``.name`` attribute as :class:`Series` or :class:`Index` (:issue:`61443`)
 - Fixed regression in :meth:`DataFrame.from_records` not initializing subclasses properly (:issue:`57008`)
+- Bug in :func:`assert_frame_equal` with ``check_dtype=False`` failing to compare DataFrames containing ``pd.NA`` that differ only in dtype (``object`` vs ``Int32``). (:issue:`61473`)
 
 .. ***DO NOT USE THIS SECTION***
 

pandas/_testing/asserters.py

@@ -1031,10 +1031,16 @@ def assert_series_equal(
         else:
             # convert both to NumPy if not, check_dtype would raise earlier
             lv, rv = left_values, right_values
-            if isinstance(left_values, ExtensionArray):
-                lv = left_values.to_numpy()
-            if isinstance(right_values, ExtensionArray):
-                rv = right_values.to_numpy()
+            if check_dtype:
+                if isinstance(left_values, ExtensionArray):
+                    lv = left_values.to_numpy()
+                if isinstance(right_values, ExtensionArray):
+                    rv = right_values.to_numpy()
+            else:
+                if isinstance(left_values, ExtensionArray):
+                    lv = left_values.to_numpy(dtype="object")
+                if isinstance(right_values, ExtensionArray):
+                    rv = right_values.to_numpy(dtype="object")
             assert_numpy_array_equal(
                 lv,
                 rv,

pandas/tests/util/test_assert_frame_equal.py

@@ -395,3 +395,11 @@ def test_assert_frame_equal_set_mismatch():
     msg = r'DataFrame.iloc\[:, 0\] \(column name="set_column"\) values are different'
     with pytest.raises(AssertionError, match=msg):
         tm.assert_frame_equal(df1, df2)
+
+
+def test_assert_frame_equal_pdNa_ignore_dtype():
+    # GH#61473
+    df1 = DataFrame({"x": pd.Series([pd.NA], dtype="Int32")})
+    df2 = DataFrame({"x": pd.Series([pd.NA], dtype="object")})
+
+    tm.assert_frame_equal(df1, df2, check_dtype=False)