Method is_env_var_to_ignore

Lib/test/test_subprocess.py:829–836

Determine if an environment variable is under our control.

(n)

        """Verify that env={} is as empty as possible."""

        def is_env_var_to_ignore(n):
            """Determine if an environment variable is under our control."""
            # This excludes some __CF_* and VERSIONER_* keys MacOS insists
            # on adding even when the environment in exec is empty.
            # Gentoo sandboxes also force LD_PRELOAD and SANDBOX_* to exist.
            return ('VERSIONER' in n or '__CF' in n or  # MacOS
                    n == 'LD_PRELOAD' or n.startswith('SANDBOX') or # Gentoo
                    n == 'LC_CTYPE') # Locale coercion triggered

        with subprocess.Popen([sys.executable, "-c",
                               'import os; print(list(os.environ.keys()))'],