test_ok1/_pytest/capture.py

613 lines
18 KiB
Python

"""
per-test stdout/stderr capturing mechanisms,
``capsys`` and ``capfd`` function arguments.
"""
# note: py.io capture was where copied from
# pylib 1.4.20.dev2 (rev 13d9af95547e)
import sys
import os
import tempfile
import py
import pytest
try:
from io import StringIO
except ImportError:
from StringIO import StringIO
try:
from io import BytesIO
except ImportError:
class BytesIO(StringIO):
def write(self, data):
if isinstance(data, unicode):
raise TypeError("not a byte value: %r" % (data,))
StringIO.write(self, data)
if sys.version_info < (3, 0):
class TextIO(StringIO):
def write(self, data):
if not isinstance(data, unicode):
enc = getattr(self, '_encoding', 'UTF-8')
data = unicode(data, enc, 'replace')
StringIO.write(self, data)
else:
TextIO = StringIO
patchsysdict = {0: 'stdin', 1: 'stdout', 2: 'stderr'}
def pytest_addoption(parser):
group = parser.getgroup("general")
group._addoption(
'--capture', action="store", default=None,
metavar="method", choices=['fd', 'sys', 'no'],
help="per-test capturing method: one of fd (default)|sys|no.")
group._addoption(
'-s', action="store_const", const="no", dest="capture",
help="shortcut for --capture=no.")
@pytest.mark.tryfirst
def pytest_load_initial_conftests(early_config, parser, args, __multicall__):
ns = parser.parse_known_args(args)
method = ns.capture
if not method:
method = "fd"
if method == "fd" and not hasattr(os, "dup"):
method = "sys"
capman = CaptureManager(method)
early_config.pluginmanager.register(capman, "capturemanager")
# make sure that capturemanager is properly reset at final shutdown
def teardown():
try:
capman.reset_capturings()
except ValueError:
pass
early_config.pluginmanager.add_shutdown(teardown)
# make sure logging does not raise exceptions at the end
def silence_logging_at_shutdown():
if "logging" in sys.modules:
sys.modules["logging"].raiseExceptions = False
early_config.pluginmanager.add_shutdown(silence_logging_at_shutdown)
# finally trigger conftest loading but while capturing (issue93)
capman.resumecapture()
try:
try:
return __multicall__.execute()
finally:
out, err = capman.suspendcapture()
except:
sys.stdout.write(out)
sys.stderr.write(err)
raise
def addouterr(rep, outerr):
for secname, content in zip(["out", "err"], outerr):
if content:
rep.sections.append(("Captured std%s" % secname, content))
class NoCapture:
def startall(self):
pass
def resume(self):
pass
def reset(self):
pass
def suspend(self):
return "", ""
class CaptureManager:
def __init__(self, defaultmethod=None):
self._method2capture = {}
self._defaultmethod = defaultmethod
def _maketempfile(self):
f = py.std.tempfile.TemporaryFile()
newf = dupfile(f, encoding="UTF-8")
f.close()
return newf
def _makestringio(self):
return TextIO()
def _getcapture(self, method):
if method == "fd":
return StdCaptureFD(
out=self._maketempfile(),
err=self._maketempfile(),
)
elif method == "sys":
return StdCapture(
out=self._makestringio(),
err=self._makestringio(),
)
elif method == "no":
return NoCapture()
else:
raise ValueError("unknown capturing method: %r" % method)
def _getmethod(self, config, fspath):
if config.option.capture:
method = config.option.capture
else:
try:
method = config._conftest.rget("option_capture", path=fspath)
except KeyError:
method = "fd"
if method == "fd" and not hasattr(os, 'dup'): # e.g. jython
method = "sys"
return method
def reset_capturings(self):
for cap in self._method2capture.values():
cap.reset()
def resumecapture_item(self, item):
method = self._getmethod(item.config, item.fspath)
if not hasattr(item, 'outerr'):
item.outerr = ('', '') # we accumulate outerr on the item
return self.resumecapture(method)
def resumecapture(self, method=None):
if hasattr(self, '_capturing'):
raise ValueError(
"cannot resume, already capturing with %r" %
(self._capturing,))
if method is None:
method = self._defaultmethod
cap = self._method2capture.get(method)
self._capturing = method
if cap is None:
self._method2capture[method] = cap = self._getcapture(method)
cap.startall()
else:
cap.resume()
def suspendcapture(self, item=None):
self.deactivate_funcargs()
if hasattr(self, '_capturing'):
method = self._capturing
cap = self._method2capture.get(method)
if cap is not None:
outerr = cap.suspend()
del self._capturing
if item:
outerr = (item.outerr[0] + outerr[0],
item.outerr[1] + outerr[1])
return outerr
if hasattr(item, 'outerr'):
return item.outerr
return "", ""
def activate_funcargs(self, pyfuncitem):
funcargs = getattr(pyfuncitem, "funcargs", None)
if funcargs is not None:
for name, capfuncarg in funcargs.items():
if name in ('capsys', 'capfd'):
assert not hasattr(self, '_capturing_funcarg')
self._capturing_funcarg = capfuncarg
capfuncarg._start()
def deactivate_funcargs(self):
capturing_funcarg = getattr(self, '_capturing_funcarg', None)
if capturing_funcarg:
outerr = capturing_funcarg._finalize()
del self._capturing_funcarg
return outerr
def pytest_make_collect_report(self, __multicall__, collector):
method = self._getmethod(collector.config, collector.fspath)
try:
self.resumecapture(method)
except ValueError:
# recursive collect, XXX refactor capturing
# to allow for more lightweight recursive capturing
return
try:
rep = __multicall__.execute()
finally:
outerr = self.suspendcapture()
addouterr(rep, outerr)
return rep
@pytest.mark.tryfirst
def pytest_runtest_setup(self, item):
self.resumecapture_item(item)
@pytest.mark.tryfirst
def pytest_runtest_call(self, item):
self.resumecapture_item(item)
self.activate_funcargs(item)
@pytest.mark.tryfirst
def pytest_runtest_teardown(self, item):
self.resumecapture_item(item)
def pytest_keyboard_interrupt(self, excinfo):
if hasattr(self, '_capturing'):
self.suspendcapture()
@pytest.mark.tryfirst
def pytest_runtest_makereport(self, __multicall__, item, call):
funcarg_outerr = self.deactivate_funcargs()
rep = __multicall__.execute()
outerr = self.suspendcapture(item)
if funcarg_outerr is not None:
outerr = (outerr[0] + funcarg_outerr[0],
outerr[1] + funcarg_outerr[1])
addouterr(rep, outerr)
if not rep.passed or rep.when == "teardown":
outerr = ('', '')
item.outerr = outerr
return rep
error_capsysfderror = "cannot use capsys and capfd at the same time"
def pytest_funcarg__capsys(request):
"""enables capturing of writes to sys.stdout/sys.stderr and makes
captured output available via ``capsys.readouterr()`` method calls
which return a ``(out, err)`` tuple.
"""
if "capfd" in request._funcargs:
raise request.raiseerror(error_capsysfderror)
return CaptureFixture(StdCapture)
def pytest_funcarg__capfd(request):
"""enables capturing of writes to file descriptors 1 and 2 and makes
captured output available via ``capsys.readouterr()`` method calls
which return a ``(out, err)`` tuple.
"""
if "capsys" in request._funcargs:
request.raiseerror(error_capsysfderror)
if not hasattr(os, 'dup'):
pytest.skip("capfd funcarg needs os.dup")
return CaptureFixture(StdCaptureFD)
class CaptureFixture:
def __init__(self, captureclass):
self._capture = captureclass()
def _start(self):
self._capture.startall()
def _finalize(self):
if hasattr(self, '_capture'):
outerr = self._outerr = self._capture.reset()
del self._capture
return outerr
def readouterr(self):
try:
return self._capture.readouterr()
except AttributeError:
return self._outerr
def close(self):
self._finalize()
class FDCapture:
""" Capture IO to/from a given os-level filedescriptor. """
def __init__(self, targetfd, tmpfile=None, patchsys=False):
""" save targetfd descriptor, and open a new
temporary file there. If no tmpfile is
specified a tempfile.Tempfile() will be opened
in text mode.
"""
self.targetfd = targetfd
if tmpfile is None and targetfd != 0:
f = tempfile.TemporaryFile('wb+')
tmpfile = dupfile(f, encoding="UTF-8")
f.close()
self.tmpfile = tmpfile
self._savefd = os.dup(self.targetfd)
if patchsys:
self._oldsys = getattr(sys, patchsysdict[targetfd])
def start(self):
try:
os.fstat(self._savefd)
except OSError:
raise ValueError(
"saved filedescriptor not valid, "
"did you call start() twice?")
if self.targetfd == 0 and not self.tmpfile:
fd = os.open(os.devnull, os.O_RDONLY)
os.dup2(fd, 0)
os.close(fd)
if hasattr(self, '_oldsys'):
setattr(sys, patchsysdict[self.targetfd], DontReadFromInput())
else:
os.dup2(self.tmpfile.fileno(), self.targetfd)
if hasattr(self, '_oldsys'):
setattr(sys, patchsysdict[self.targetfd], self.tmpfile)
def done(self):
""" unpatch and clean up, returns the self.tmpfile (file object)
"""
os.dup2(self._savefd, self.targetfd)
os.close(self._savefd)
if self.targetfd != 0:
self.tmpfile.seek(0)
if hasattr(self, '_oldsys'):
setattr(sys, patchsysdict[self.targetfd], self._oldsys)
return self.tmpfile
def writeorg(self, data):
""" write a string to the original file descriptor
"""
tempfp = tempfile.TemporaryFile()
try:
os.dup2(self._savefd, tempfp.fileno())
tempfp.write(data)
finally:
tempfp.close()
def dupfile(f, mode=None, buffering=0, raising=False, encoding=None):
""" return a new open file object that's a duplicate of f
mode is duplicated if not given, 'buffering' controls
buffer size (defaulting to no buffering) and 'raising'
defines whether an exception is raised when an incompatible
file object is passed in (if raising is False, the file
object itself will be returned)
"""
try:
fd = f.fileno()
mode = mode or f.mode
except AttributeError:
if raising:
raise
return f
newfd = os.dup(fd)
if sys.version_info >= (3, 0):
if encoding is not None:
mode = mode.replace("b", "")
buffering = True
return os.fdopen(newfd, mode, buffering, encoding, closefd=True)
else:
f = os.fdopen(newfd, mode, buffering)
if encoding is not None:
return EncodedFile(f, encoding)
return f
class EncodedFile(object):
def __init__(self, _stream, encoding):
self._stream = _stream
self.encoding = encoding
def write(self, obj):
if isinstance(obj, unicode):
obj = obj.encode(self.encoding)
self._stream.write(obj)
def writelines(self, linelist):
data = ''.join(linelist)
self.write(data)
def __getattr__(self, name):
return getattr(self._stream, name)
class Capture(object):
def reset(self):
""" reset sys.stdout/stderr and return captured output as strings. """
if hasattr(self, '_reset'):
raise ValueError("was already reset")
self._reset = True
outfile, errfile = self.done(save=False)
out, err = "", ""
if outfile and not outfile.closed:
out = outfile.read()
outfile.close()
if errfile and errfile != outfile and not errfile.closed:
err = errfile.read()
errfile.close()
return out, err
def suspend(self):
""" return current snapshot captures, memorize tempfiles. """
outerr = self.readouterr()
outfile, errfile = self.done()
return outerr
class StdCaptureFD(Capture):
""" This class allows to capture writes to FD1 and FD2
and may connect a NULL file to FD0 (and prevent
reads from sys.stdin). If any of the 0,1,2 file descriptors
is invalid it will not be captured.
"""
def __init__(self, out=True, err=True, in_=True, patchsys=True):
self._options = {
"out": out,
"err": err,
"in_": in_,
"patchsys": patchsys,
}
self._save()
def _save(self):
in_ = self._options['in_']
out = self._options['out']
err = self._options['err']
patchsys = self._options['patchsys']
if in_:
try:
self.in_ = FDCapture(
0, tmpfile=None,
patchsys=patchsys)
except OSError:
pass
if out:
tmpfile = None
if hasattr(out, 'write'):
tmpfile = out
try:
self.out = FDCapture(
1, tmpfile=tmpfile,
patchsys=patchsys)
self._options['out'] = self.out.tmpfile
except OSError:
pass
if err:
if hasattr(err, 'write'):
tmpfile = err
else:
tmpfile = None
try:
self.err = FDCapture(
2, tmpfile=tmpfile,
patchsys=patchsys)
self._options['err'] = self.err.tmpfile
except OSError:
pass
def startall(self):
if hasattr(self, 'in_'):
self.in_.start()
if hasattr(self, 'out'):
self.out.start()
if hasattr(self, 'err'):
self.err.start()
def resume(self):
""" resume capturing with original temp files. """
self.startall()
def done(self, save=True):
""" return (outfile, errfile) and stop capturing. """
outfile = errfile = None
if hasattr(self, 'out') and not self.out.tmpfile.closed:
outfile = self.out.done()
if hasattr(self, 'err') and not self.err.tmpfile.closed:
errfile = self.err.done()
if hasattr(self, 'in_'):
self.in_.done()
if save:
self._save()
return outfile, errfile
def readouterr(self):
""" return snapshot value of stdout/stderr capturings. """
out = self._readsnapshot('out')
err = self._readsnapshot('err')
return out, err
def _readsnapshot(self, name):
if hasattr(self, name):
f = getattr(self, name).tmpfile
else:
return ''
f.seek(0)
res = f.read()
enc = getattr(f, "encoding", None)
if enc:
res = py.builtin._totext(res, enc, "replace")
f.truncate(0)
f.seek(0)
return res
class StdCapture(Capture):
""" This class allows to capture writes to sys.stdout|stderr "in-memory"
and will raise errors on tries to read from sys.stdin. It only
modifies sys.stdout|stderr|stdin attributes and does not
touch underlying File Descriptors (use StdCaptureFD for that).
"""
def __init__(self, out=True, err=True, in_=True):
self._oldout = sys.stdout
self._olderr = sys.stderr
self._oldin = sys.stdin
if out and not hasattr(out, 'file'):
out = TextIO()
self.out = out
if err:
if not hasattr(err, 'write'):
err = TextIO()
self.err = err
self.in_ = in_
def startall(self):
if self.out:
sys.stdout = self.out
if self.err:
sys.stderr = self.err
if self.in_:
sys.stdin = self.in_ = DontReadFromInput()
def done(self, save=True):
""" return (outfile, errfile) and stop capturing. """
outfile = errfile = None
if self.out and not self.out.closed:
sys.stdout = self._oldout
outfile = self.out
outfile.seek(0)
if self.err and not self.err.closed:
sys.stderr = self._olderr
errfile = self.err
errfile.seek(0)
if self.in_:
sys.stdin = self._oldin
return outfile, errfile
def resume(self):
""" resume capturing with original temp files. """
self.startall()
def readouterr(self):
""" return snapshot value of stdout/stderr capturings. """
out = err = ""
if self.out:
out = self.out.getvalue()
self.out.truncate(0)
self.out.seek(0)
if self.err:
err = self.err.getvalue()
self.err.truncate(0)
self.err.seek(0)
return out, err
class DontReadFromInput:
"""Temporary stub class. Ideally when stdin is accessed, the
capturing should be turned off, with possibly all data captured
so far sent to the screen. This should be configurable, though,
because in automated test runs it is better to crash than
hang indefinitely.
"""
def read(self, *args):
raise IOError("reading from stdin while output is captured")
readline = read
readlines = read
__iter__ = read
def fileno(self):
raise ValueError("redirected Stdin is pseudofile, has no fileno()")
def isatty(self):
return False
def close(self):
pass