Add compatibility module to fix failing tests on Python 3.5 due to missing functionality.

4 files changed, 77 insertions, 3 deletions

diff --git a/distutils/tests/py35compat.py b/distutils/tests/py35compat.py
new file mode 100644
index 00000000..3eb86b5f
--- /dev/null
+++ b/distutils/tests/py35compat.py
@@ -0,0 +1,68 @@
+"""
+Backward compatibility support for Python 3.5
+"""
+
+import sys
+import test.support
+import subprocess
+
+
+# copied from Python 3.9 test.support module
+def _missing_compiler_executable(cmd_names=[]):
+    """Check if the compiler components used to build the interpreter exist.
+
+    Check for the existence of the compiler executables whose names are listed
+    in 'cmd_names' or all the compiler executables when 'cmd_names' is empty
+    and return the first missing executable or None when none is found
+    missing.
+
+    """
+    from distutils import ccompiler, sysconfig, spawn
+    compiler = ccompiler.new_compiler()
+    sysconfig.customize_compiler(compiler)
+    for name in compiler.executables:
+        if cmd_names and name not in cmd_names:
+            continue
+        cmd = getattr(compiler, name)
+        if cmd_names:
+            assert cmd is not None, \
+                    "the '%s' executable is not configured" % name
+        elif not cmd:
+            continue
+        if spawn.find_executable(cmd[0]) is None:
+            return cmd[0]
+
+
+missing_compiler_executable = vars(test.support).setdefault(
+    'missing_compiler_executable',
+    _missing_compiler_executable,
+)
+
+
+try:
+    from test.support import unix_shell
+except ImportError:
+    # Adapted from Python 3.9 test.support module
+    is_android = hasattr(sys, 'getandroidapilevel')
+    unix_shell = (
+        None if sys.platform == 'win32' else
+        '/system/bin/sh' if is_android else
+        '/bin/sh'
+    )
+
+
+# copied from Python 3.9 subprocess module
+def _optim_args_from_interpreter_flags():
+    """Return a list of command-line arguments reproducing the current
+    optimization settings in sys.flags."""
+    args = []
+    value = sys.flags.optimize
+    if value > 0:
+        args.append('-' + 'O' * value)
+    return args
+
+
+vars(subprocess).setdefault(
+    '_optim_args_from_interpreter_flags',
+    _optim_args_from_interpreter_flags,
+)
diff --git a/distutils/tests/test_build_clib.py b/distutils/tests/test_build_clib.py
index abd83137..259c4352 100644
--- a/distutils/tests/test_build_clib.py
+++ b/distutils/tests/test_build_clib.py
@@ -3,7 +3,9 @@ import unittest
 import os
 import sys
 
-from test.support import run_unittest, missing_compiler_executable
+from test.support import run_unittest
+
+from .py35compat import missing_compiler_executable
 
 from distutils.command.build_clib import build_clib
 from distutils.errors import DistutilsSetupError
diff --git a/distutils/tests/test_config_cmd.py b/distutils/tests/test_config_cmd.py
index 9aeab07b..4cd9a6b9 100644
--- a/distutils/tests/test_config_cmd.py
+++ b/distutils/tests/test_config_cmd.py
@@ -2,7 +2,9 @@
 import unittest
 import os
 import sys
-from test.support import run_unittest, missing_compiler_executable
+from test.support import run_unittest
+
+from .py35compat import missing_compiler_executable
 
 from distutils.command.config import dump_file, config
 from distutils.tests import support
diff --git a/distutils/tests/test_spawn.py b/distutils/tests/test_spawn.py
index cf1faad5..919d0ad9 100644
--- a/distutils/tests/test_spawn.py
+++ b/distutils/tests/test_spawn.py
@@ -3,9 +3,11 @@ import os
 import stat
 import sys
 import unittest.mock
-from test.support import run_unittest, unix_shell
+from test.support import run_unittest
 from test import support as test_support
 
+from .py35compat import unix_shell
+
 from distutils.spawn import find_executable
 from distutils.spawn import spawn
 from distutils.errors import DistutilsExecError