qutebrowser/tests/integration/testprocess.py
2015-10-14 21:52:11 +02:00

136 lines
3.9 KiB
Python

# vim: ft=python fileencoding=utf-8 sts=4 sw=4 et:
# Copyright 2015 Florian Bruhin (The Compiler) <mail@qutebrowser.org>
#
# This file is part of qutebrowser.
#
# qutebrowser is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# qutebrowser is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with qutebrowser. If not, see <http://www.gnu.org/licenses/>.
"""Base class for a subprocess run for tests.."""
import pytestqt.plugin # pylint: disable=import-error
from PyQt5.QtCore import pyqtSlot, pyqtSignal, QProcess, QObject
class InvalidLine(Exception):
"""Raised when the process prints a line which is not parsable."""
pass
class ProcessExited(Exception):
"""Raised when the child process did exit."""
pass
class Process(QObject):
"""Abstraction over a running test subprocess process.
Reads the log from its stdout and parses it.
Signals:
new_data: Emitted when a new line was parsed.
"""
new_data = pyqtSignal(object)
def __init__(self, parent=None):
super().__init__(parent)
self._invalid = False
self._data = []
self.proc = QProcess()
self.proc.setReadChannel(QProcess.StandardError)
def _parse_line(self, line):
"""Parse the given line from the log.
Return:
A self.ParseResult member.
"""
raise NotImplementedError
def _executable_args(self):
"""Get the executable and arguments to pass to it as a tuple."""
raise NotImplementedError
def _get_data(self):
"""Get the parsed data for this test.
Also waits for 0.5s to make sure any new data is received.
Subprocesses are expected to alias this to a public method with a
better name.
"""
self.proc.waitForReadyRead(500)
self.read_log()
return self._data
@pyqtSlot()
def read_log(self):
"""Read the log from the process' stdout."""
while self.proc.canReadLine():
line = self.proc.readLine()
line = bytes(line).decode('utf-8').rstrip('\r\n')
print(line)
try:
parsed = self._parse_line(line)
except InvalidLine:
self._invalid = True
print("INVALID: {}".format(line))
continue
print('parsed: {}'.format(parsed))
if parsed is not None:
self._data.append(parsed)
self.new_data.emit(parsed)
def start(self):
"""Start the process and wait until it started."""
blocker = pytestqt.plugin.SignalBlocker(timeout=5000, raising=True)
blocker.connect(self.ready)
with blocker:
self._start()
def _start(self):
"""Actually start the process."""
executable, args = self._executable_args()
self.proc.start(executable, args)
ok = self.proc.waitForStarted()
assert ok
self.proc.readyRead.connect(self.read_log)
def after_test(self):
"""Clean up data after each test.
Also checks self._invalid so the test counts as failed if there were
unexpected output lines earlier.
"""
self._data.clear()
if self.proc.state() != QProcess.Running:
print("Restarting process...")
self.start()
raise ProcessExited
if self._invalid:
raise InvalidLine
def cleanup(self):
"""Clean up and shut down the process."""
self.proc.terminate()
self.proc.waitForFinished()