Make the stdlib test suite helper test.script_helper._assert_python no longer

pass -I or -E to the child process by default when the environment is required
for the child process interpreter to function properly.

1 files changed, 3 insertions, 2 deletions

diff --git a/Lib/test/script_helper.py b/Lib/test/script_helper.py
index 6a8bea6..8c599d1 100644
--- a/Lib/test/script_helper.py
+++ b/Lib/test/script_helper.py
@@ -52,16 +52,17 @@ def _interpreter_requires_environment():
 
 # Executing the interpreter in a subprocess
 def _assert_python(expected_success, *args, **env_vars):
+    env_required = _interpreter_requires_environment()
     if '__isolated' in env_vars:
         isolated = env_vars.pop('__isolated')
     else:
-        isolated = not env_vars
+        isolated = not env_vars and not env_required
     cmd_line = [sys.executable, '-X', 'faulthandler']
     if isolated:
         # isolated mode: ignore Python environment variables, ignore user
         # site-packages, and don't add the current directory to sys.path
         cmd_line.append('-I')
-    elif not env_vars:
+    elif not env_vars and not env_required:
         # ignore Python environment variables
         cmd_line.append('-E')
     # Need to preserve the original environment, for in-place testing of