bpo-40275: Use new test.support helper submodules in tests (GH-21151)

Use new test.support helper submodules in tests:

* distutils tests
* test_buffer
* test_compile
* test_filecmp
* test_fileinput
* test_readline
* test_smtpnet
* test_structmembers
* test_tools

Author: shihai1991

Lib/distutils/tests/test_archive_util.py

@@ -13,7 +13,9 @@
                                     ARCHIVE_FORMATS)
 from distutils.spawn import find_executable, spawn
 from distutils.tests import support
-from test.support import check_warnings, run_unittest, patch, change_cwd
+from test.support import run_unittest, patch
+from test.support.os_helper import change_cwd
+from test.support.warnings_helper import check_warnings
 
 try:
     import grp

Lib/distutils/tests/test_bdist_msi.py

@@ -1,7 +1,8 @@
 """Tests for distutils.command.bdist_msi."""
 import sys
 import unittest
-from test.support import run_unittest, check_warnings
+from test.support import run_unittest
+from test.support.warnings_helper import check_warnings
 from distutils.tests import support
 
 

Lib/distutils/tests/test_bdist_wininst.py

@@ -2,7 +2,8 @@
 import sys
 import platform
 import unittest
-from test.support import run_unittest, check_warnings
+from test.support import run_unittest
+from test.support.warnings_helper import check_warnings
 
 from distutils.command.bdist_wininst import bdist_wininst
 from distutils.tests import support

Lib/distutils/tests/test_core.py

@@ -5,8 +5,8 @@
 import os
 import shutil
 import sys
-import test.support
 from test.support import captured_stdout, run_unittest
+from test.support import os_helper
 import unittest
 from distutils.tests import support
 from distutils import log
@@ -62,13 +62,13 @@ def tearDown(self):
         super(CoreTestCase, self).tearDown()
 
     def cleanup_testfn(self):
-        path = test.support.TESTFN
+        path = os_helper.TESTFN
         if os.path.isfile(path):
             os.remove(path)
         elif os.path.isdir(path):
             shutil.rmtree(path)
 
-    def write_setup(self, text, path=test.support.TESTFN):
+    def write_setup(self, text, path=os_helper.TESTFN):
         f = open(path, "w")
         try:
             f.write(text)
@@ -105,8 +105,8 @@ def test_run_setup_uses_current_dir(self):
         cwd = os.getcwd()
 
         # Create a directory and write the setup.py file there:
-        os.mkdir(test.support.TESTFN)
-        setup_py = os.path.join(test.support.TESTFN, "setup.py")
+        os.mkdir(os_helper.TESTFN)
+        setup_py = os.path.join(os_helper.TESTFN, "setup.py")
         distutils.core.run_setup(
             self.write_setup(setup_prints_cwd, path=setup_py))
 

Lib/distutils/tests/test_dist.py

@@ -12,8 +12,9 @@
 from distutils.cmd import Command
 
 from test.support import (
-     TESTFN, captured_stdout, captured_stderr, run_unittest
+     captured_stdout, captured_stderr, run_unittest
 )
+from test.support.os_helper import TESTFN
 from distutils.tests import support
 from distutils import log
 

Lib/distutils/tests/test_extension.py

@@ -3,7 +3,8 @@
 import os
 import warnings
 
-from test.support import check_warnings, run_unittest
+from test.support import run_unittest
+from test.support.warnings_helper import check_warnings
 from distutils.extension import read_setup_file, Extension
 
 class ExtensionTestCase(unittest.TestCase):

Lib/distutils/tests/test_file_util.py

@@ -8,7 +8,9 @@
 from distutils import log
 from distutils.tests import support
 from distutils.errors import DistutilsFileError
-from test.support import run_unittest, unlink
+from test.support import run_unittest
+from test.support.os_helper import unlink
+
 
 class FileUtilTestCase(support.TempdirManager, unittest.TestCase):
 

Lib/distutils/tests/test_filelist.py

@@ -9,6 +9,7 @@
 from distutils import filelist
 
 import test.support
+from test.support import os_helper
 from test.support import captured_stdout, run_unittest
 from distutils.tests import support
 
@@ -295,7 +296,7 @@ def test_process_template(self):
 
 
 class FindAllTestCase(unittest.TestCase):
-    @test.support.skip_unless_symlink
+    @os_helper.skip_unless_symlink
     def test_missing_symlink(self):
         with test.support.temp_cwd():
             os.symlink('foo', 'bar')

Lib/distutils/tests/test_register.py

@@ -5,7 +5,8 @@
 import urllib
 import warnings
 
-from test.support import check_warnings, run_unittest
+from test.support import run_unittest
+from test.support.warnings_helper import check_warnings
 
 from distutils.command import register as register_module
 from distutils.command.register import register

Lib/distutils/tests/test_sdist.py

@@ -6,7 +6,8 @@
 import zipfile
 from os.path import join
 from textwrap import dedent
-from test.support import captured_stdout, check_warnings, run_unittest
+from test.support import captured_stdout, run_unittest
+from test.support.warnings_helper import check_warnings
 
 try:
     import zlib