Run test in isolation. Helper utility for invoking scripts that need to be run in isolation

python/pyarrow/tests/arrow_7980.py

@@ -0,0 +1,30 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you 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.
+
+# This file is called from a test in test_schema.py.
+
+import pyarrow as pa
+
+
+# the types where to_pandas_dtype returns a non-numpy dtype
+cases = [
+    (pa.timestamp('ns', tz='UTC'), "datetime64[ns, UTC]"),
+]
+
+
+for arrow_type, pandas_type in cases:
+    assert str(arrow_type.to_pandas_dtype()) == pandas_type

python/pyarrow/tests/test_schema.py

@@ -23,6 +23,8 @@ import pytest
 import numpy as np
 import pyarrow as pa
 
+import pyarrow.tests.util as test_util
+
 
 def test_schema_constructor_errors():
     msg = ("Do not call Schema's constructor directly, use `pyarrow.schema` "
@@ -71,13 +73,9 @@ def test_type_to_pandas_dtype():
 
 
 @pytest.mark.pandas
-def test_type_to_pandas_dtype2():
-    # the types where to_pandas_dtype returns a non-numpy dtype
-    cases = [
-        (pa.timestamp('ns', tz='UTC'), "datetime64[ns, UTC]"),
-    ]
-    for arrow_type, pandas_type in cases:
-        assert str(arrow_type.to_pandas_dtype()) == pandas_type
+def test_type_to_pandas_dtype_check_import():
+    # ARROW-7980
+    test_util.invoke_script('arrow_7980.py')
 
 
 def test_type_list():

python/pyarrow/tests/test_serialization.py

@@ -952,12 +952,7 @@ def test_deserialize_buffer_in_different_process():
     f.write(b.to_pybytes())
     f.close()
 
-    subprocess_env = test_util.get_modified_env_with_pythonpath()
-
-    dir_path = os.path.dirname(os.path.realpath(__file__))
-    python_file = os.path.join(dir_path, 'deserialize_buffer.py')
-    subprocess.check_call([sys.executable, python_file, f.name],
-                          env=subprocess_env)
+    test_util.invoke_script('deserialize_buffer.py', f.name)
 
 
 def test_set_pickle():

python/pyarrow/tests/util.py

@@ -25,6 +25,8 @@ import numpy as np
 import os
 import random
 import string
+import subprocess
+import sys
 
 import pyarrow as pa
 
@@ -136,3 +138,15 @@ def get_modified_env_with_pythonpath():
         new_pythonpath = module_path
     env['PYTHONPATH'] = new_pythonpath
     return env
+
+
+def invoke_script(script_name, *args):
+    subprocess_env = get_modified_env_with_pythonpath()
+
+    dir_path = os.path.dirname(os.path.realpath(__file__))
+    python_file = os.path.join(dir_path, script_name)
+
+    cmd = [sys.executable, python_file]
+    cmd.extend(args)
+
+    subprocess.check_call(cmd, env=subprocess_env)