name : script_helper.py # Common utility functions used by various script execution tests # e.g. test_cmd_line, test_cmd_line_script and test_runpy import collections import importlib import sys import os import os.path import tempfile import subprocess import py_compile import contextlib import shutil import zipfile from importlib.util import source_from_cache from test.support import make_legacy_pyc, strip_python_stderr # Cached result of the expensive test performed in the function below. __cached_interp_requires_environment = None def interpreter_requires_environment(): """ Returns True if our 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 & 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. """ global __cached_interp_requires_environment if __cached_interp_requires_environment is None: # If PYTHONHOME is set, assume that we need it if 'PYTHONHOME' in os.environ: __cached_interp_requires_environment = True return True # Try running an interpreter with -E to see if it works or not. try: subprocess.check_call([sys.executable, '-E', '-c', 'import sys; sys.exit(0)']) except subprocess.CalledProcessError: __cached_interp_requires_environment = True else: __cached_interp_requires_environment = False return __cached_interp_requires_environment class _PythonRunResult(collections.namedtuple("_PythonRunResult", ("rc", "out", "err"))): """Helper for reporting Python subprocess run results""" def fail(self, cmd_line): """Provide helpful details about failed subcommand runs""" # Limit to 80 lines to ASCII characters maxlen = 80 * 100 out, err = self.out, self.err if len(out) > maxlen: out = b'(... truncated stdout ...)' + out[-maxlen:] if len(err) > maxlen: err = b'(... truncated stderr ...)' + err[-maxlen:] out = out.decode('ascii', 'replace').rstrip() err = err.decode('ascii', 'replace').rstrip() raise AssertionError("Process return code is %d\n" "command line: %r\n" "\n" "stdout:\n" "---\n" "%s\n" "---\n" "\n" "stderr:\n" "---\n" "%s\n" "---" % (self.rc, cmd_line, out, err)) # Executing the interpreter in a subprocess def run_python_until_end(*args, **env_vars): env_required = interpreter_requires_environment() if '__isolated' in env_vars: isolated = env_vars.pop('__isolated') else: 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 and not env_required: # ignore Python environment variables cmd_line.append('-E') # But a special flag that can be set to override -- in this case, the # caller is responsible to pass the full environment. if env_vars.pop('__cleanenv', None): env = {} if sys.platform == 'win32': # Windows requires at least the SYSTEMROOT environment variable to # start Python. env['SYSTEMROOT'] = os.environ['SYSTEMROOT'] # Other interesting environment variables, not copied currently: # COMSPEC, HOME, PATH, TEMP, TMPDIR, TMP. else: # Need to preserve the original environment, for in-place testing of # shared library builds. env = os.environ.copy() # set TERM='' unless the TERM environment variable is passed explicitly # see issues #11390 and #18300 if 'TERM' not in env_vars: env['TERM'] = '' env.update(env_vars) cmd_line.extend(args) proc = subprocess.Popen(cmd_line, stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE, env=env) with proc: try: out, err = proc.communicate() finally: proc.kill() subprocess._cleanup() rc = proc.returncode err = strip_python_stderr(err) return _PythonRunResult(rc, out, err), cmd_line def _assert_python(expected_success, *args, **env_vars): res, cmd_line = run_python_until_end(*args, **env_vars) if (res.rc and expected_success) or (not res.rc and not expected_success): res.fail(cmd_line) return res def assert_python_ok(*args, **env_vars): """ 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 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 is set to False. """ return _assert_python(True, *args, **env_vars) def assert_python_failure(*args, **env_vars): """ 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. """ return _assert_python(False, *args, **env_vars) def spawn_python(*args, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, **kw): """Run a Python subprocess with the given arguments. kw is extra keyword args to pass to subprocess.Popen. Returns a Popen object. """ cmd_line = [sys.executable] if not interpreter_requires_environment(): cmd_line.append('-E') cmd_line.extend(args) # Under Fedora (?), GNU readline can output junk on stderr when initialized, # depending on the TERM setting. Setting TERM=vt100 is supposed to disable # that. References: # - http://reinout.vanrees.org/weblog/2009/08/14/readline-invisible-character-hack.html # - http://stackoverflow.com/questions/15760712/python-readline-module-prints-escape-character-during-import # - http://lists.gnu.org/archive/html/bug-readline/2007-08/msg00004.html env = kw.setdefault('env', dict(os.environ)) env['TERM'] = 'vt100' return subprocess.Popen(cmd_line, stdin=subprocess.PIPE, stdout=stdout, stderr=stderr, **kw) def kill_python(p): """Run the given Popen process until completion and return stdout.""" p.stdin.close() data = p.stdout.read() p.stdout.close() # try to cleanup the child so we don't appear to leak when running # with regrtest -R. p.wait() subprocess._cleanup() return data def make_script(script_dir, script_basename, source, omit_suffix=False): script_filename = script_basename if not omit_suffix: script_filename += os.extsep + 'py' script_name = os.path.join(script_dir, script_filename) # The script should be encoded to UTF-8, the default string encoding script_file = open(script_name, 'w', encoding='utf-8') script_file.write(source) script_file.close() importlib.invalidate_caches() return script_name def make_zip_script(zip_dir, zip_basename, script_name, name_in_zip=None): zip_filename = zip_basename+os.extsep+'zip' zip_name = os.path.join(zip_dir, zip_filename) zip_file = zipfile.ZipFile(zip_name, 'w') if name_in_zip is None: parts = script_name.split(os.sep) if len(parts) >= 2 and parts[-2] == '__pycache__': legacy_pyc = make_legacy_pyc(source_from_cache(script_name)) name_in_zip = os.path.basename(legacy_pyc) script_name = legacy_pyc else: name_in_zip = os.path.basename(script_name) zip_file.write(script_name, name_in_zip) zip_file.close() #if test.support.verbose: # zip_file = zipfile.ZipFile(zip_name, 'r') # print 'Contents of %r:' % zip_name # zip_file.printdir() # zip_file.close() return zip_name, os.path.join(zip_name, name_in_zip) def make_pkg(pkg_dir, init_source=''): os.mkdir(pkg_dir) make_script(pkg_dir, '__init__', init_source) def make_zip_pkg(zip_dir, zip_basename, pkg_name, script_basename, source, depth=1, compiled=False): unlink = [] init_name = make_script(zip_dir, '__init__', '') unlink.append(init_name) init_basename = os.path.basename(init_name) script_name = make_script(zip_dir, script_basename, source) unlink.append(script_name) if compiled: init_name = py_compile.compile(init_name, doraise=True) script_name = py_compile.compile(script_name, doraise=True) unlink.extend((init_name, script_name)) pkg_names = [os.sep.join([pkg_name]*i) for i in range(1, depth+1)] script_name_in_zip = os.path.join(pkg_names[-1], os.path.basename(script_name)) zip_filename = zip_basename+os.extsep+'zip' zip_name = os.path.join(zip_dir, zip_filename) zip_file = zipfile.ZipFile(zip_name, 'w') for name in pkg_names: init_name_in_zip = os.path.join(name, init_basename) zip_file.write(init_name, init_name_in_zip) zip_file.write(script_name, script_name_in_zip) zip_file.close() for name in unlink: os.unlink(name) #if test.support.verbose: # zip_file = zipfile.ZipFile(zip_name, 'r') # print 'Contents of %r:' % zip_name # zip_file.printdir() # zip_file.close() return zip_name, os.path.join(zip_name, script_name_in_zip)