Fix for legate data interface

cunumeric/array.py

@@ -200,9 +200,12 @@ def __legate_data_interface__(self):
             # so we just need to convert our type and stick it in
             # a Legate Array
             arrow_type = pyarrow.from_numpy_dtype(self.dtype)
+            # If the thunk is an eager array, we need to convert it to a
+            # deferred array so we can extract a legate store
+            deferred_thunk = runtime.to_deferred_array(self._thunk)
             # We don't have nullable data for the moment
             # until we support masked arrays
-            array = Array(arrow_type, [None, self._thunk])
+            array = Array(arrow_type, [None, deferred_thunk.base])
             self._legate_data = dict()
             self._legate_data["version"] = 1
             data = dict()

tests/integration/test_data_interface.py

@@ -0,0 +1,41 @@
+# Copyright 2022 NVIDIA Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+import pytest
+
+import cunumeric as num
+
+
+# A simple wrapper with a legate data interface implementation for testing
+class Wrapper:
+    def __init__(self, wrapped):
+        self.wrapped = wrapped
+
+    @property
+    def __legate_data_interface__(self):
+        return self.wrapped
+
+
+def test_roundtrip():
+    arr1 = num.array([1, 2, 3, 4], dtype=num.float64)
+    data = Wrapper(arr1.__legate_data_interface__)
+    arr2 = num.asarray(data)
+    assert num.array_equal(arr1, arr2)
+
+
+if __name__ == "__main__":
+    import sys
+
+    sys.exit(pytest.main(sys.argv))