Files
neon/test_runner/fixtures/utils.py
Dmitry Ivanov 96c7594d29 Enable some kind of gradual typing in test_runner (#222)
It's not realistic to enable full-blown type checks
within test_runner's codebase, since the amount of
warnings revealed by mypy is overwhelming.

Tests are supposed to be easy to use, so we can't
cripple everybody's workflow for the sake of imaginary benefit.

Ultimately, the purpose of this attempt is three-fold:

* Facilitate code navigation when paired with python-language-server.
* Make method signatures apparent to a fellow programmer.
* Occasionally catch some obvious type errors.
2021-06-10 22:53:15 +03:00

56 lines
1.6 KiB
Python

import os
import subprocess
from typing import Any, List
def get_self_dir() -> str:
""" Get the path to the directory where this script lives. """
return os.path.dirname(os.path.abspath(__file__))
def mkdir_if_needed(path: str) -> None:
""" Create a directory if it doesn't already exist
Note this won't try to create intermediate directories.
"""
if os.path.exists(path):
assert os.path.isdir(path)
return
os.mkdir(path)
def subprocess_capture(capture_dir: str, cmd: List[str], **kwargs: Any) -> None:
""" Run a process and capture its output
Output will go to files named "cmd_NNN.stdout" and "cmd_NNN.stderr"
where "cmd" is the name of the program and NNN is an incrementing
counter.
If those files already exist, we will overwrite them.
"""
assert type(cmd) is list
base = os.path.basename(cmd[0]) + '_{}'.format(global_counter())
basepath = os.path.join(capture_dir, base)
stdout_filename = basepath + '.stdout'
stderr_filename = basepath + '.stderr'
with open(stdout_filename, 'w') as stdout_f:
with open(stderr_filename, 'w') as stderr_f:
print('(capturing output to "{}.stdout")'.format(base))
subprocess.run(cmd, **kwargs, stdout=stdout_f, stderr=stderr_f)
_global_counter = 0
def global_counter() -> int:
""" A really dumb global counter.
This is useful for giving output files a unique number, so if we run the
same command multiple times we can keep their output separate.
"""
global _global_counter
_global_counter += 1
return _global_counter