# test --- Regression tests package for Python — test.support.script_helper --- Utilities for the Python execution tests

> synopsis: Support for Python's script execution tests. The !test.support.script_helper module provides support for Python's script execution tests. Return True if sys.executable interpreter requires environment variables in order to be able to run at all. This is designed to be used with @unittest.s

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- Canonical URL: <https://wikikv.com/k/ref-python-78faae1926e2d0f57b46>
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- Updated: `2026-08-16T09:32:14.537926+00:00`
- Tags: `reference-seed`, `python`, `library`, `test`, `regression`, `tests`, `package`, `support`, `script`, `helper`, `utilities`, `execution`

## Provenance

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## Knowledge

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synopsis: Support for Python's script execution tests.

The !test.support.script_helper module provides support for Python's script execution tests.

Return True if sys.executable interpreter requires environment variables in order to be able to run at all.

This is designed to be used with @unittest.skipIf() to annotate tests that need to use an assert_python() function to launch an isolated mode (-I) or no environment mode (-E) sub-interpreter process.

A normal build &amp; test does not run into this situation but it can happen when trying to run the standard library test suite from an interpreter that doesn't have an obvious home with Python's current home finding logic.

Setting PYTHONHOME is one way to get most of the testsuite to run in that situation. PYTHONPATH or PYTHONUSERSITE are other common environment variables that might impact whether or not the interpreter can start.

Set up the environment based on env_vars for running the interpreter in a subprocess. The values can include isolated, cleanenv, cwd, and TERM.

Assert that running the interpreter with args and optional environment variables env_vars succeeds (rc == 0) and return a (return code, stdout, stderr) tuple.

If the cleanenv keyword-only parameter is set, env_vars is used as a fresh environment.

Python is started in isolated mode (command line option -I), except if the isolated keyword-only parameter is set to False.

Assert that running the interpreter with args and optional environment variables env_vars fails (rc != 0) and return a (return code, stdout, stderr) tuple.

See assert_python_ok for more options.

Run a Python subprocess with the given arguments.

kw is extra keyword args to pass to subprocess.Popen. Returns a subprocess.Popen object.

Run the given subprocess.Popen process until completion and return stdout.

Create script containing source in path script_dir and script_basename. If omit_suffix is False, append .py to the name. Return the full script path.

Create zip file at zip_dir and zip_basename with extension zip which contains the files in script_name. name_in_zip is the archive name. Return a tuple containing (full path, full path of archive name).

Create a directory named pkg_dir containing an init file with init_source as its contents. …

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