Redo the Capture integration propperly

CHANGELOG

@@ -15,9 +15,15 @@ UNRELEASED
   correctly also on python2 and with pytest-xdist runs. (the fix
   requires py-1.4.20)
 
+- copy, cleanup and integrate py.io capture
+  from pylib 1.4.20.dev2 (rev 13d9af95547e)
+  
 - address issue416: clarify docs as to conftest.py loading semantics
 
 
+- make capfd/capsys.capture private, its unused and shouldnt be exposed
+
+
 2.5.1
 -----------------------------------
 

_pytest/capture.py

@@ -1,17 +1,55 @@
-""" per-test stdout/stderr capturing mechanisms, ``capsys`` and ``capfd`` function arguments.  """
+"""
-
+    per-test stdout/stderr capturing mechanisms,
-import pytest, py
+    ``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,
+    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",
+    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)
@@ -22,13 +60,16 @@ def pytest_load_initial_conftests(early_config, parser, args, __multicall__):
         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:
@@ -47,21 +88,27 @@ def pytest_load_initial_conftests(early_config, parser, args, __multicall__):
         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 = {}
@@ -69,21 +116,25 @@ class CaptureManager:
 
     def _maketempfile(self):
         f = py.std.tempfile.TemporaryFile()
-        newf = py.io.dupfile(f, encoding="UTF-8")
+        newf = dupfile(f, encoding="UTF-8")
         f.close()
         return newf
 
     def _makestringio(self):
-        return py.io.TextIO()
+        return TextIO()
 
     def _getcapture(self, method):
         if method == "fd":
-            return py.io.StdCaptureFD(now=False,
+            return StdCaptureFD(
-                out=self._maketempfile(), err=self._maketempfile()
+                now=False,
+                out=self._maketempfile(),
+                err=self._maketempfile(),
             )
         elif method == "sys":
-            return py.io.StdCapture(now=False,
+            return StdCapture(
-                out=self._makestringio(), err=self._makestringio()
+                now=False,
+                out=self._makestringio(),
+                err=self._makestringio(),
             )
         elif method == "no":
             return NoCapture()
@@ -98,23 +149,24 @@ class CaptureManager:
                 method = config._conftest.rget("option_capture", path=fspath)
             except KeyError:
                 method = "fd"
-        if method == "fd" and not hasattr(os, 'dup'): # e.g. jython
+        if method == "fd" and not hasattr(os, 'dup'):  # e.g. jython
             method = "sys"
         return method
 
     def reset_capturings(self):
-        for name, cap in self._method2capture.items():
+        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
+            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" %
+            raise ValueError(
+                "cannot resume, already capturing with %r" %
                 (self._capturing,))
         if method is None:
             method = self._defaultmethod
@@ -163,8 +215,9 @@ class CaptureManager:
         try:
             self.resumecapture(method)
         except ValueError:
-            return # recursive collect, XXX refactor capturing
+            # recursive collect, XXX refactor capturing
-                   # to allow for more lightweight recursive capturing
+            # to allow for more lightweight recursive capturing
+            return
         try:
             rep = __multicall__.execute()
         finally:
@@ -205,6 +258,7 @@ class CaptureManager:
 
 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
@@ -212,7 +266,8 @@ def pytest_funcarg__capsys(request):
     """
     if "capfd" in request._funcargs:
         raise request.raiseerror(error_capsysfderror)
-    return CaptureFixture(py.io.StdCapture)
+    return CaptureFixture(StdCapture)
+
 
 def pytest_funcarg__capfd(request):
     """enables capturing of writes to file descriptors 1 and 2 and makes
@@ -223,26 +278,366 @@ def pytest_funcarg__capfd(request):
         request.raiseerror(error_capsysfderror)
     if not hasattr(os, 'dup'):
         pytest.skip("capfd funcarg needs os.dup")
-    return CaptureFixture(py.io.StdCaptureFD)
+    return CaptureFixture(StdCaptureFD)
+
 
 class CaptureFixture:
     def __init__(self, captureclass):
-        self.capture = captureclass(now=False)
+        self._capture = captureclass(now=False)
 
     def _start(self):
-        self.capture.startall()
+        self._capture.startall()
 
     def _finalize(self):
-        if hasattr(self, 'capture'):
+        if hasattr(self, '_capture'):
-            outerr = self._outerr = self.capture.reset()
+            outerr = self._outerr = self._capture.reset()
-            del self.capture
+            del self._capture
             return outerr
 
     def readouterr(self):
         try:
-            return self.capture.readouterr()
+            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, now=True, 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])
+        if now:
+            self.start()
+
+    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 call(cls, func, *args, **kwargs):
+        """ return a (res, out, err) tuple where
+            out and err represent the output/error output
+            during function execution.
+            call the given function with args/kwargs
+            and capture output/error during its execution.
+        """
+        so = cls()
+        try:
+            res = func(*args, **kwargs)
+        finally:
+            out, err = so.reset()
+        return res, out, err
+    call = classmethod(call)
+
+    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, mixed=False,
+                 in_=True, patchsys=True, now=True):
+        self._options = {
+            "out": out,
+            "err": err,
+            "mixed": mixed,
+            "in_": in_,
+            "patchsys": patchsys,
+            "now": now,
+        }
+        self._save()
+        if now:
+            self.startall()
+
+    def _save(self):
+        in_ = self._options['in_']
+        out = self._options['out']
+        err = self._options['err']
+        mixed = self._options['mixed']
+        patchsys = self._options['patchsys']
+        if in_:
+            try:
+                self.in_ = FDCapture(
+                    0, tmpfile=None, now=False,
+                    patchsys=patchsys)
+            except OSError:
+                pass
+        if out:
+            tmpfile = None
+            if hasattr(out, 'write'):
+                tmpfile = out
+            try:
+                self.out = FDCapture(
+                    1, tmpfile=tmpfile,
+                    now=False, patchsys=patchsys)
+                self._options['out'] = self.out.tmpfile
+            except OSError:
+                pass
+        if err:
+            if out and mixed:
+                tmpfile = self.out.tmpfile
+            elif hasattr(err, 'write'):
+                tmpfile = err
+            else:
+                tmpfile = None
+            try:
+                self.err = FDCapture(
+                    2, tmpfile=tmpfile,
+                    now=False, 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, mixed=False, now=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 mixed:
+                err = out
+            elif not hasattr(err, 'write'):
+                err = TextIO()
+        self.err = err
+        self.in_ = in_
+        if now:
+            self.startall()
+
+    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

testing/test_capture.py

@@ -1,8 +1,48 @@
-import pytest, py, os, sys
+# note: py.io capture tests where copied from
+# pylib 1.4.20.dev2 (rev 13d9af95547e)
+from __future__ import with_statement
+import os
+import sys
+import py
+import pytest
+
+from _pytest import capture
 from _pytest.capture import CaptureManager
+from py.builtin import print_
 
 needsosdup = pytest.mark.xfail("not hasattr(os, 'dup')")
 
+if sys.version_info >= (3, 0):
+    def tobytes(obj):
+        if isinstance(obj, str):
+            obj = obj.encode('UTF-8')
+        assert isinstance(obj, bytes)
+        return obj
+
+    def totext(obj):
+        if isinstance(obj, bytes):
+            obj = str(obj, 'UTF-8')
+        assert isinstance(obj, str)
+        return obj
+else:
+    def tobytes(obj):
+        if isinstance(obj, unicode):
+            obj = obj.encode('UTF-8')
+        assert isinstance(obj, str)
+        return obj
+
+    def totext(obj):
+        if isinstance(obj, str):
+            obj = unicode(obj, 'UTF-8')
+        assert isinstance(obj, unicode)
+        return obj
+
+
+def oswritebytes(fd, obj):
+    os.write(fd, tobytes(obj))
+
+
+
 class TestCaptureManager:
     def test_getmethod_default_no_fd(self, testdir, monkeypatch):
         config = testdir.parseconfig(testdir.tmpdir)
@@ -34,7 +74,7 @@ class TestCaptureManager:
     @needsosdup
     @pytest.mark.parametrize("method", ['no', 'fd', 'sys'])
     def test_capturing_basic_api(self, method):
-        capouter = py.io.StdCaptureFD()
+        capouter = capture.StdCaptureFD()
         old = sys.stdout, sys.stderr, sys.stdin
         try:
             capman = CaptureManager()
@@ -58,7 +98,7 @@ class TestCaptureManager:
 
     @needsosdup
     def test_juggle_capturings(self, testdir):
-        capouter = py.io.StdCaptureFD()
+        capouter = capture.StdCaptureFD()
         try:
             #config = testdir.parseconfig(testdir.tmpdir)
             capman = CaptureManager()
@@ -80,10 +120,11 @@ class TestCaptureManager:
         finally:
             capouter.reset()
 
+
 @pytest.mark.xfail("hasattr(sys, 'pypy_version_info')")
 @pytest.mark.parametrize("method", ['fd', 'sys'])
 def test_capturing_unicode(testdir, method):
-    if sys.version_info >= (3,0):
+    if sys.version_info >= (3, 0):
         obj = "'b\u00f6y'"
     else:
         obj = "u'\u00f6y'"
@@ -100,6 +141,7 @@ def test_capturing_unicode(testdir, method):
         "*1 passed*"
     ])
 
+
 @pytest.mark.parametrize("method", ['fd', 'sys'])
 def test_capturing_bytes_in_utf8_encoding(testdir, method):
     testdir.makepyfile("""
@@ -111,6 +153,7 @@ def test_capturing_bytes_in_utf8_encoding(testdir, method):
         "*1 passed*"
     ])
 
+
 def test_collect_capturing(testdir):
     p = testdir.makepyfile("""
         print ("collect %s failure" % 13)
@@ -122,6 +165,7 @@ def test_collect_capturing(testdir):
         "*collect 13 failure*",
     ])
 
+
 class TestPerTestCapturing:
     def test_capture_and_fixtures(self, testdir):
         p = testdir.makepyfile("""
@@ -169,7 +213,6 @@ class TestPerTestCapturing:
             "in teardown*",
         ])
 
-
     def test_no_carry_over(self, testdir):
         p = testdir.makepyfile("""
             def test_func1():
@@ -183,7 +226,6 @@ class TestPerTestCapturing:
         assert "in func1" not in s
         assert "in func2" in s
 
-
     def test_teardown_capturing(self, testdir):
         p = testdir.makepyfile("""
             def setup_function(function):
@@ -244,13 +286,14 @@ class TestPerTestCapturing:
             "2",
         ])
 
+
 class TestLoggingInteraction:
     def test_logging_stream_ownership(self, testdir):
         p = testdir.makepyfile("""
             def test_logging():
                 import logging
                 import pytest
-                stream = py.io.TextIO()
+                stream = capture.TextIO()
                 logging.basicConfig(stream=stream)
                 stream.close() # to free memory/release resources
         """)
@@ -320,7 +363,8 @@ class TestLoggingInteraction:
                 logging.warn("hello432")
                 assert 0
         """)
-        result = testdir.runpytest(p, "--traceconfig",
+        result = testdir.runpytest(
+            p, "--traceconfig",
             "-p", "no:capturelog")
         assert result.ret != 0
         result.stdout.fnmatch_lines([
@@ -461,6 +505,7 @@ def test_setup_failure_does_not_kill_capturing(testdir):
         "*1 error*"
     ])
 
+
 def test_fdfuncarg_skips_on_no_osdup(testdir):
     testdir.makepyfile("""
         import os
@@ -474,6 +519,7 @@ def test_fdfuncarg_skips_on_no_osdup(testdir):
         "*1 skipped*"
     ])
 
+
 def test_capture_conftest_runtest_setup(testdir):
     testdir.makeconftest("""
         def pytest_runtest_setup():
@@ -484,6 +530,7 @@ def test_capture_conftest_runtest_setup(testdir):
     assert result.ret == 0
     assert 'hello19' not in result.stdout.str()
 
+
 def test_capture_early_option_parsing(testdir):
     testdir.makeconftest("""
         def pytest_runtest_setup():
@@ -494,9 +541,10 @@ def test_capture_early_option_parsing(testdir):
     assert result.ret == 0
     assert 'hello19' in result.stdout.str()
 
-@pytest.mark.xfail(reason='encoding issues')
+
+@pytest.mark.xfail(sys.version_info >= (3, 0), reason='encoding issues')
 def test_capture_binary_output(testdir):
-    testdir.makepyfile("""
+    testdir.makepyfile(r"""
         import pytest
 
         def test_a():
@@ -516,3 +564,499 @@ def test_capture_binary_output(testdir):
         '*2 passed*',
     ])
 
+
+class TestTextIO:
+    def test_text(self):
+        f = capture.TextIO()
+        f.write("hello")
+        s = f.getvalue()
+        assert s == "hello"
+        f.close()
+
+    def test_unicode_and_str_mixture(self):
+        f = capture.TextIO()
+        if sys.version_info >= (3, 0):
+            f.write("\u00f6")
+            pytest.raises(TypeError, "f.write(bytes('hello', 'UTF-8'))")
+        else:
+            f.write(unicode("\u00f6", 'UTF-8'))
+            f.write("hello")  # bytes
+            s = f.getvalue()
+            f.close()
+            assert isinstance(s, unicode)
+
+
+def test_bytes_io():
+    f = capture.BytesIO()
+    f.write(tobytes("hello"))
+    pytest.raises(TypeError, "f.write(totext('hello'))")
+    s = f.getvalue()
+    assert s == tobytes("hello")
+
+
+def test_dontreadfrominput():
+    from _pytest.capture import DontReadFromInput
+    f = DontReadFromInput()
+    assert not f.isatty()
+    pytest.raises(IOError, f.read)
+    pytest.raises(IOError, f.readlines)
+    pytest.raises(IOError, iter, f)
+    pytest.raises(ValueError, f.fileno)
+    f.close()  # just for completeness
+
+
+def pytest_funcarg__tmpfile(request):
+    testdir = request.getfuncargvalue("testdir")
+    f = testdir.makepyfile("").open('wb+')
+    request.addfinalizer(f.close)
+    return f
+
+
+@needsosdup
+def test_dupfile(tmpfile):
+    flist = []
+    for i in range(5):
+        nf = capture.dupfile(tmpfile, encoding="utf-8")
+        assert nf != tmpfile
+        assert nf.fileno() != tmpfile.fileno()
+        assert nf not in flist
+        print_(i, end="", file=nf)
+        flist.append(nf)
+    for i in range(5):
+        f = flist[i]
+        f.close()
+    tmpfile.seek(0)
+    s = tmpfile.read()
+    assert "01234" in repr(s)
+    tmpfile.close()
+
+
+def test_dupfile_no_mode():
+    """
+    dupfile should trap an AttributeError and return f if no mode is supplied.
+    """
+    class SomeFileWrapper(object):
+        "An object with a fileno method but no mode attribute"
+        def fileno(self):
+            return 1
+    tmpfile = SomeFileWrapper()
+    assert capture.dupfile(tmpfile) is tmpfile
+    with pytest.raises(AttributeError):
+        capture.dupfile(tmpfile, raising=True)
+
+
+def lsof_check(func):
+    pid = os.getpid()
+    try:
+        out = py.process.cmdexec("lsof -p %d" % pid)
+    except py.process.cmdexec.Error:
+        pytest.skip("could not run 'lsof'")
+    func()
+    out2 = py.process.cmdexec("lsof -p %d" % pid)
+    len1 = len([x for x in out.split("\n") if "REG" in x])
+    len2 = len([x for x in out2.split("\n") if "REG" in x])
+    assert len2 < len1 + 3, out2
+
+
+class TestFDCapture:
+    pytestmark = needsosdup
+
+    def test_not_now(self, tmpfile):
+        fd = tmpfile.fileno()
+        cap = capture.FDCapture(fd, now=False)
+        data = tobytes("hello")
+        os.write(fd, data)
+        f = cap.done()
+        s = f.read()
+        assert not s
+        cap = capture.FDCapture(fd, now=False)
+        cap.start()
+        os.write(fd, data)
+        f = cap.done()
+        s = f.read()
+        assert s == "hello"
+
+    def test_simple(self, tmpfile):
+        fd = tmpfile.fileno()
+        cap = capture.FDCapture(fd)
+        data = tobytes("hello")
+        os.write(fd, data)
+        f = cap.done()
+        s = f.read()
+        assert s == "hello"
+        f.close()
+
+    def test_simple_many(self, tmpfile):
+        for i in range(10):
+            self.test_simple(tmpfile)
+
+    def test_simple_many_check_open_files(self, tmpfile):
+        lsof_check(lambda: self.test_simple_many(tmpfile))
+
+    def test_simple_fail_second_start(self, tmpfile):
+        fd = tmpfile.fileno()
+        cap = capture.FDCapture(fd)
+        f = cap.done()
+        pytest.raises(ValueError, cap.start)
+        f.close()
+
+    def test_stderr(self):
+        cap = capture.FDCapture(2, patchsys=True)
+        print_("hello", file=sys.stderr)
+        f = cap.done()
+        s = f.read()
+        assert s == "hello\n"
+
+    def test_stdin(self, tmpfile):
+        tmpfile.write(tobytes("3"))
+        tmpfile.seek(0)
+        cap = capture.FDCapture(0, tmpfile=tmpfile)
+        # check with os.read() directly instead of raw_input(), because
+        # sys.stdin itself may be redirected (as pytest now does by default)
+        x = os.read(0, 100).strip()
+        cap.done()
+        assert x == tobytes("3")
+
+    def test_writeorg(self, tmpfile):
+        data1, data2 = tobytes("foo"), tobytes("bar")
+        try:
+            cap = capture.FDCapture(tmpfile.fileno())
+            tmpfile.write(data1)
+            cap.writeorg(data2)
+        finally:
+            tmpfile.close()
+        f = cap.done()
+        scap = f.read()
+        assert scap == totext(data1)
+        stmp = open(tmpfile.name, 'rb').read()
+        assert stmp == data2
+
+
+class TestStdCapture:
+    def getcapture(self, **kw):
+        return capture.StdCapture(**kw)
+
+    def test_capturing_done_simple(self):
+        cap = self.getcapture()
+        sys.stdout.write("hello")
+        sys.stderr.write("world")
+        outfile, errfile = cap.done()
+        s = outfile.read()
+        assert s == "hello"
+        s = errfile.read()
+        assert s == "world"
+
+    def test_capturing_reset_simple(self):
+        cap = self.getcapture()
+        print("hello world")
+        sys.stderr.write("hello error\n")
+        out, err = cap.reset()
+        assert out == "hello world\n"
+        assert err == "hello error\n"
+
+    def test_capturing_readouterr(self):
+        cap = self.getcapture()
+        try:
+            print ("hello world")
+            sys.stderr.write("hello error\n")
+            out, err = cap.readouterr()
+            assert out == "hello world\n"
+            assert err == "hello error\n"
+            sys.stderr.write("error2")
+        finally:
+            out, err = cap.reset()
+        assert err == "error2"
+
+    def test_capturing_readouterr_unicode(self):
+        cap = self.getcapture()
+        try:
+            print ("hx\xc4\x85\xc4\x87")
+            out, err = cap.readouterr()
+        finally:
+            cap.reset()
+        assert out == py.builtin._totext("hx\xc4\x85\xc4\x87\n", "utf8")
+
+    @pytest.mark.skipif('sys.version_info >= (3,)',
+                        reason='text output different for bytes on python3')
+    def test_capturing_readouterr_decode_error_handling(self):
+        cap = self.getcapture()
+        # triggered a internal error in pytest
+        print('\xa6')
+        out, err = cap.readouterr()
+        assert out == py.builtin._totext('\ufffd\n', 'unicode-escape')
+
+    def test_capturing_mixed(self):
+        cap = self.getcapture(mixed=True)
+        sys.stdout.write("hello ")
+        sys.stderr.write("world")
+        sys.stdout.write(".")
+        out, err = cap.reset()
+        assert out.strip() == "hello world."
+        assert not err
+
+    def test_reset_twice_error(self):
+        cap = self.getcapture()
+        print ("hello")
+        out, err = cap.reset()
+        pytest.raises(ValueError, cap.reset)
+        assert out == "hello\n"
+        assert not err
+
+    def test_capturing_modify_sysouterr_in_between(self):
+        oldout = sys.stdout
+        olderr = sys.stderr
+        cap = self.getcapture()
+        sys.stdout.write("hello")
+        sys.stderr.write("world")
+        sys.stdout = capture.TextIO()
+        sys.stderr = capture.TextIO()
+        print ("not seen")
+        sys.stderr.write("not seen\n")
+        out, err = cap.reset()
+        assert out == "hello"
+        assert err == "world"
+        assert sys.stdout == oldout
+        assert sys.stderr == olderr
+
+    def test_capturing_error_recursive(self):
+        cap1 = self.getcapture()
+        print ("cap1")
+        cap2 = self.getcapture()
+        print ("cap2")
+        out2, err2 = cap2.reset()
+        out1, err1 = cap1.reset()
+        assert out1 == "cap1\n"
+        assert out2 == "cap2\n"
+
+    def test_just_out_capture(self):
+        cap = self.getcapture(out=True, err=False)
+        sys.stdout.write("hello")
+        sys.stderr.write("world")
+        out, err = cap.reset()
+        assert out == "hello"
+        assert not err
+
+    def test_just_err_capture(self):
+        cap = self.getcapture(out=False, err=True)
+        sys.stdout.write("hello")
+        sys.stderr.write("world")
+        out, err = cap.reset()
+        assert err == "world"
+        assert not out
+
+    def test_stdin_restored(self):
+        old = sys.stdin
+        cap = self.getcapture(in_=True)
+        newstdin = sys.stdin
+        out, err = cap.reset()
+        assert newstdin != sys.stdin
+        assert sys.stdin is old
+
+    def test_stdin_nulled_by_default(self):
+        print ("XXX this test may well hang instead of crashing")
+        print ("XXX which indicates an error in the underlying capturing")
+        print ("XXX mechanisms")
+        cap = self.getcapture()
+        pytest.raises(IOError, "sys.stdin.read()")
+        out, err = cap.reset()
+
+    def test_suspend_resume(self):
+        cap = self.getcapture(out=True, err=False, in_=False)
+        try:
+            print ("hello")
+            sys.stderr.write("error\n")
+            out, err = cap.suspend()
+            assert out == "hello\n"
+            assert not err
+            print ("in between")
+            sys.stderr.write("in between\n")
+            cap.resume()
+            print ("after")
+            sys.stderr.write("error_after\n")
+        finally:
+            out, err = cap.reset()
+        assert out == "after\n"
+        assert not err
+
+
+class TestStdCaptureNotNow(TestStdCapture):
+    def getcapture(self, **kw):
+        kw['now'] = False
+        cap = capture.StdCapture(**kw)
+        cap.startall()
+        return cap
+
+
+class TestStdCaptureFD(TestStdCapture):
+    pytestmark = needsosdup
+
+    def getcapture(self, **kw):
+        return capture.StdCaptureFD(**kw)
+
+    def test_intermingling(self):
+        cap = self.getcapture()
+        oswritebytes(1, "1")
+        sys.stdout.write(str(2))
+        sys.stdout.flush()
+        oswritebytes(1, "3")
+        oswritebytes(2, "a")
+        sys.stderr.write("b")
+        sys.stderr.flush()
+        oswritebytes(2, "c")
+        out, err = cap.reset()
+        assert out == "123"
+        assert err == "abc"
+
+    def test_callcapture(self):
+        def func(x, y):
+            print (x)
+            sys.stderr.write(str(y))
+            return 42
+
+        res, out, err = capture.StdCaptureFD.call(func, 3, y=4)
+        assert res == 42
+        assert out.startswith("3")
+        assert err.startswith("4")
+
+    def test_many(self, capfd):
+        def f():
+            for i in range(10):
+                cap = capture.StdCaptureFD()
+                cap.reset()
+        lsof_check(f)
+
+
+class TestStdCaptureFDNotNow(TestStdCaptureFD):
+    pytestmark = needsosdup
+
+    def getcapture(self, **kw):
+        kw['now'] = False
+        cap = capture.StdCaptureFD(**kw)
+        cap.startall()
+        return cap
+
+
+@needsosdup
+def test_stdcapture_fd_tmpfile(tmpfile):
+    capfd = capture.StdCaptureFD(out=tmpfile)
+    try:
+        os.write(1, "hello".encode("ascii"))
+        os.write(2, "world".encode("ascii"))
+        outf, errf = capfd.done()
+    finally:
+        capfd.reset()
+    assert outf == tmpfile
+
+
+class TestStdCaptureFDinvalidFD:
+    pytestmark = needsosdup
+
+    def test_stdcapture_fd_invalid_fd(self, testdir):
+        testdir.makepyfile("""
+            import os
+            from _pytest.capture import StdCaptureFD
+            def test_stdout():
+                os.close(1)
+                cap = StdCaptureFD(out=True, err=False, in_=False)
+                cap.done()
+            def test_stderr():
+                os.close(2)
+                cap = StdCaptureFD(out=False, err=True, in_=False)
+                cap.done()
+            def test_stdin():
+                os.close(0)
+                cap = StdCaptureFD(out=False, err=False, in_=True)
+                cap.done()
+        """)
+        result = testdir.runpytest("--capture=fd")
+        assert result.ret == 0
+        assert result.parseoutcomes()['passed'] == 3
+
+
+def test_capture_not_started_but_reset():
+    capsys = capture.StdCapture(now=False)
+    capsys.done()
+    capsys.done()
+    capsys.reset()
+
+
+@needsosdup
+def test_capture_no_sys():
+    capsys = capture.StdCapture()
+    try:
+        cap = capture.StdCaptureFD(patchsys=False)
+        sys.stdout.write("hello")
+        sys.stderr.write("world")
+        oswritebytes(1, "1")
+        oswritebytes(2, "2")
+        out, err = cap.reset()
+        assert out == "1"
+        assert err == "2"
+    finally:
+        capsys.reset()
+
+
+@needsosdup
+def test_callcapture_nofd():
+    def func(x, y):
+        oswritebytes(1, "hello")
+        oswritebytes(2, "hello")
+        print (x)
+        sys.stderr.write(str(y))
+        return 42
+
+    capfd = capture.StdCaptureFD(patchsys=False)
+    try:
+        res, out, err = capture.StdCapture.call(func, 3, y=4)
+    finally:
+        capfd.reset()
+    assert res == 42
+    assert out.startswith("3")
+    assert err.startswith("4")
+
+
+@needsosdup
+@pytest.mark.parametrize('use', [True, False])
+def test_fdcapture_tmpfile_remains_the_same(tmpfile, use):
+    if not use:
+        tmpfile = True
+    cap = capture.StdCaptureFD(out=False, err=tmpfile, now=False)
+    try:
+        cap.startall()
+        capfile = cap.err.tmpfile
+        cap.suspend()
+        cap.resume()
+    finally:
+        cap.reset()
+    capfile2 = cap.err.tmpfile
+    assert capfile2 == capfile
+
+
+@pytest.mark.parametrize('method', ['StdCapture', 'StdCaptureFD'])
+def test_capturing_and_logging_fundamentals(testdir, method):
+    if method == "StdCaptureFD" and not hasattr(os, 'dup'):
+        pytest.skip("need os.dup")
+    # here we check a fundamental feature
+    p = testdir.makepyfile("""
+        import sys, os
+        import py, logging
+        from _pytest import capture
+        cap = capture.%s(out=False, in_=False)
+
+        logging.warn("hello1")
+        outerr = cap.suspend()
+        print ("suspend, captured %%s" %%(outerr,))
+        logging.warn("hello2")
+
+        cap.resume()
+        logging.warn("hello3")
+
+        outerr = cap.suspend()
+        print ("suspend2, captured %%s" %% (outerr,))
+    """ % (method,))
+    result = testdir.runpython(p)
+    result.stdout.fnmatch_lines([
+        "suspend, captured*hello1*",
+        "suspend2, captured*hello2*WARNING:root:hello3*",
+    ])
+    assert "atexit" not in result.stderr.str()