Isolate globals in import sanity test.

test/sanity/import/importer.py

@@ -3,53 +3,55 @@
 from __future__ import (absolute_import, division, print_function)
 __metaclass__ = type
 
-import contextlib
-import os
-import re
-import sys
-import traceback
-import warnings
-
-try:
+
+def main():
+    """
+    Main program function used to isolate globals from imported code.
+    Changes to globals in imported modules on Python 2.7 will overwrite our own globals.
+    """
+    import contextlib
+    import os
+    import re
+    import sys
+    import traceback
+    import warnings
+
+    try:
         import importlib.util
         imp = None  # pylint: disable=invalid-name
-except ImportError:
+    except ImportError:
         importlib = None  # pylint: disable=invalid-name
         import imp
 
-try:
+    try:
         from StringIO import StringIO
-except ImportError:
+    except ImportError:
         from io import StringIO
 
-import ansible.module_utils.basic
-import ansible.module_utils.common.removed
+    import ansible.module_utils.basic
+    import ansible.module_utils.common.removed
 
-try:
+    try:
         from ansible.utils.collection_loader import AnsibleCollectionLoader
-except ImportError:
+    except ImportError:
         AnsibleCollectionLoader = None
 
-
-class ImporterAnsibleModuleException(Exception):
+    class ImporterAnsibleModuleException(Exception):
         """Exception thrown during initialization of ImporterAnsibleModule."""
 
-
-class ImporterAnsibleModule:
+    class ImporterAnsibleModule:
         """Replacement for AnsibleModule to support import testing."""
         def __init__(self, *args, **kwargs):
             raise ImporterAnsibleModuleException()
 
+    # stop Ansible module execution during AnsibleModule instantiation
+    ansible.module_utils.basic.AnsibleModule = ImporterAnsibleModule
+    # no-op for _load_params since it may be called before instantiating AnsibleModule
+    ansible.module_utils.basic._load_params = lambda *args, **kwargs: {}  # pylint: disable=protected-access
+    # no-op for removed_module since it is called in place of AnsibleModule instantiation
+    ansible.module_utils.common.removed.removed_module = lambda *args, **kwargs: None
 
-# stop Ansible module execution during AnsibleModule instantiation
-ansible.module_utils.basic.AnsibleModule = ImporterAnsibleModule
-# no-op for _load_params since it may be called before instantiating AnsibleModule
-ansible.module_utils.basic._load_params = lambda *args, **kwargs: {}  # pylint: disable=protected-access
-# no-op for removed_module since it is called in place of AnsibleModule instantiation
-ansible.module_utils.common.removed.removed_module = lambda *args, **kwargs: None
-
-
-def main():
+    def run():
         """Main program function."""
         base_dir = os.getcwd()
         messages = set()
@@ -65,8 +67,7 @@ def main():
         if messages:
             exit(10)
 
-
-def test_python_module(path, base_dir, messages, ansible_module):
+    def test_python_module(path, base_dir, messages, ansible_module):
         if ansible_module:
             # importing modules with __main__ under Python 2.6 exits with status code 1
             if sys.version_info < (2, 7):
@@ -149,16 +150,14 @@ def test_python_module(path, base_dir, messages, ansible_module):
 
             report_message(error, messages)
 
-
-class Capture:
+    class Capture:
         """Captured output and/or exception."""
         def __init__(self):
             self.stdout = StringIO()
             self.stderr = StringIO()
             self.warnings = []
 
-
-def capture_report(path, capture, messages):
+    def capture_report(path, capture, messages):
         """Report on captured output.
         :type path: str
         :type capture: Capture
@@ -198,8 +197,7 @@ def capture_report(path, capture, messages):
             message = '%s:%d:%d: %s: %s' % (filepath, lineno, 0, warning.category.__name__, msg)
             report_message(message, messages)
 
-
-def report_message(message, messages):
+    def report_message(message, messages):
         """Report message if not already reported.
         :type message: str
         :type messages: set[str]
@@ -208,9 +206,8 @@ def report_message(message, messages):
             messages.add(message)
             print(message)
 
-
-@contextlib.contextmanager
-def capture_output(capture):
+    @contextlib.contextmanager
+    def capture_output(capture):
         """Capture sys.stdout and sys.stderr.
         :type capture: Capture
         """
@@ -229,6 +226,8 @@ def capture_output(capture):
                 sys.stdout = old_stdout
                 sys.stderr = old_stderr
 
+    run()
+
 
 if __name__ == '__main__':
     main()