fixup

Author: TomAugspurger

pandas/core/arrays/numpy_.py

@@ -4,13 +4,15 @@
 
 from pandas._libs import lib
 from pandas.compat.numpy import function as nv
+from pandas.util._validators import validate_fillna_kwargs
 
 from pandas.core.dtypes.dtypes import ExtensionDtype
 from pandas.core.dtypes.generic import ABCIndexClass, ABCSeries
-from pandas.core.dtypes.inference import is_list_like
+from pandas.core.dtypes.inference import is_array_like, is_list_like
 
 from pandas import compat
 from pandas.core import nanops
+from pandas.core.missing import backfill_1d, pad_1d
 
 from .base import ExtensionArray, ExtensionOpsMixin
 
@@ -114,7 +116,9 @@ class PandasArray(ExtensionArray, ExtensionOpsMixin, NDArrayOperatorsMixin):
     def __init__(self, values):
         if isinstance(values, type(self)):
             values = values._ndarray
-        values = np.asarray(values)
+        if not isinstance(values, np.ndarray):
+            raise ValueError("'values' must be a NumPy array.")
+
         if values.ndim != 1:
             raise ValueError("PandasArray must be 1-dimensional.")
 
@@ -242,10 +246,6 @@ def isna(self):
         return isna(self._ndarray)
 
     def fillna(self, value=None, method=None, limit=None):
-        from pandas.api.types import is_array_like
-        from pandas.util._validators import validate_fillna_kwargs
-        from pandas.core.missing import pad_1d, backfill_1d
-
         # TODO(_values_for_fillna): remove this
         value, method = validate_fillna_kwargs(value, method)
 

pandas/tests/arrays/test_numpy.py

@@ -56,7 +56,7 @@ def test_validate_reduction_keyword_args():
 
 @td.skip_if_no("numpy", min_version="1.13.0")
 def test_ufunc():
-    arr = PandasArray([-1.0, 0.0, 1.0])
+    arr = PandasArray(np.array([-1.0, 0.0, 1.0]))
     result = np.abs(arr)
     expected = PandasArray(np.abs(arr._ndarray))
     tm.assert_extension_array_equal(result, expected)
@@ -73,12 +73,17 @@ def test_ufunc():
 def test_basic_binop():
     # Just a basic smoke test. The EA interface tests exercise this
     # more thoroughly.
-    x = PandasArray([1, 2, 3])
+    x = PandasArray(np.array([1, 2, 3]))
     result = x + x
-    expected = PandasArray([2, 4, 6])
+    expected = PandasArray(np.array([2, 4, 6]))
     tm.assert_extension_array_equal(result, expected)
 
 
+def test_constructor_no_coercion():
+    with pytest.raises(ValueError, match='NumPy array'):
+        PandasArray([1, 2, 3])
+
+
 def test_series_constructor_with_copy():
     ndarray = np.array([1, 2, 3])
     ser = pd.Series(PandasArray(ndarray), copy=True)