shell_tools_test.py

# Copyright 2018 The Cirq Developers
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import subprocess
import os

import pytest

from dev_tools import shell_tools


def only_on_posix(func):
    if os.name != 'posix':
        return None
    return func


def run_cmd(*args, **kwargs):
    return shell_tools.run_cmd(*args, log_run_to_stderr=False, **kwargs)


def run_shell(*args, **kwargs):
    return shell_tools.run_shell(*args, log_run_to_stderr=False, **kwargs)


@only_on_posix
def test_run_cmd_raise_on_fail():
    assert run_cmd('true') == (None, None, 0)
    assert run_cmd('true', raise_on_fail=False) == (None, None, 0)

    with pytest.raises(subprocess.CalledProcessError):
        run_cmd('false')
    assert run_cmd('false', raise_on_fail=False) == (None, None, 1)


@only_on_posix
def test_run_shell_raise_on_fail():
    assert run_shell('true') == (None, None, 0)
    assert run_shell('true', raise_on_fail=False) == (None, None, 0)

    with pytest.raises(subprocess.CalledProcessError):
        run_shell('false')
    assert run_shell('false', raise_on_fail=False) == (None, None, 1)


@only_on_posix
def test_run_cmd_capture():
    assert run_cmd('echo', 'test', out=None) == (None, None, 0)
    assert run_cmd('echo', 'test',
                   out=shell_tools.TeeCapture()) == ('test\n', None, 0)
    assert run_cmd('echo', 'test', out=None,
                   err=shell_tools.TeeCapture()) == (None, '', 0)


@only_on_posix
def test_run_shell_capture():
    assert run_shell('echo test 1>&2', err=None) == (None, None, 0)
    assert run_shell('echo test 1>&2',
                     err=shell_tools.TeeCapture()) == (None, 'test\n', 0)
    assert run_shell('echo test 1>&2', err=None,
                     out=shell_tools.TeeCapture()) == ('', None, 0)


@only_on_posix
def test_run_shell_does_not_deadlock_on_large_outputs():
    assert run_shell(
        r"""python3 -c "import sys;"""
        r"""print((('o' * 99) + '\n') * 10000);"""
        r"""print((('e' * 99) + '\n') * 10000, file=sys.stderr)"""
        '"',
        out=None,
        err=None) == (None, None, 0)


@only_on_posix
def test_output_of():
    assert shell_tools.output_of('true') == ''
    with pytest.raises(subprocess.CalledProcessError):
        _ = shell_tools.output_of('false')
    assert shell_tools.output_of('echo', 'test') == 'test'
    assert shell_tools.output_of('pwd', cwd='/tmp') in ['/tmp', '/private/tmp']