[WIP] Investigating/fixing capsysbin

.pre-commit-config.yaml

@@ -1,9 +1,4 @@
 repos:
--   repo: https://github.com/psf/black
-    rev: 19.10b0
-    hooks:
-    -   id: black
-        args: [--safe, --quiet]
 -   repo: https://github.com/asottile/blacken-docs
     rev: v1.0.0
     hooks:

src/_pytest/capture.py

@@ -2,7 +2,6 @@
 per-test stdout/stderr capturing mechanism.
 
 """
-import collections
 import contextlib
 import io
 import os
@@ -12,7 +11,9 @@
 from typing import BinaryIO
 from typing import Generator
 from typing import Iterable
+from typing import NamedTuple
 from typing import Optional
+from typing import Union
 
 import pytest
 from _pytest.compat import CaptureAndPassthroughIO
@@ -439,7 +440,11 @@ def __getattr__(self, name):
         return getattr(object.__getattribute__(self, "buffer"), name)
 
 
-CaptureResult = collections.namedtuple("CaptureResult", ["out", "err"])
+# XXX: Generic[AnyStr], and AnyStr as type directly does not work?
+#      Would be good to ensure out and err are of the same type.
+class CaptureResult(NamedTuple):
+    out: None  # type: Union[str, bytes]
+    err: None  # type: Union[str, bytes]
 
 
 class MultiCapture:
@@ -682,7 +687,8 @@ def resume(self):
         setattr(sys, self.name, self.tmpfile)
         self._state = "resumed"
 
-    def writeorg(self, data):
+    def writeorg(self, data: str) -> None:
+        data = data.decode(self._old.encoding)
         self._old.write(data)
         self._old.flush()
 
@@ -696,6 +702,10 @@ def snap(self):
         self.tmpfile.truncate()
         return res
 
+    def writeorg(self, data: str) -> None:
+        self._old.write(data)
+        self._old.flush()
+
 
 class TeeSysCapture(SysCapture):
     def __init__(self, fd, tmpfile=None):

testing/test_capture.py

@@ -16,8 +16,10 @@
 from _pytest import capture
 from _pytest.capture import _get_multicapture
 from _pytest.capture import CaptureManager
+from _pytest.capture import CaptureResult
 from _pytest.capture import MultiCapture
 from _pytest.config import ExitCode
+from _pytest.pytester import Testdir
 
 # note: py.io capture tests where copied from
 # pylib 1.4.20.dev2 (rev 13d9af95547e)
@@ -40,6 +42,44 @@ def TeeStdCapture(out=True, err=True, in_=True):
     return capture.MultiCapture(out, err, in_, Capture=capture.TeeSysCapture)
 
 
+def test_CaptureResult() -> None:
+    with pytest.raises(TypeError):
+        CaptureResult()  # type: ignore
+
+    cr = CaptureResult(out="out", err="err")
+    repr_ = repr(cr)
+    assert repr_ == "CaptureResult(out='out', err='err')"
+    assert str(cr) == repr_
+
+    cr = CaptureResult(out=b"out\nout2", err=b"err\nerr2")
+    repr_ = repr(cr)
+    assert repr_ == r"CaptureResult(out=b'out\nout2', err=b'err\nerr2')"
+    assert str(cr) == repr_
+
+    # XXX: should cause mypy type error?!
+    cr = CaptureResult(out="out", err=b"err")
+    repr_ = repr(cr)
+    assert repr_ == r"CaptureResult(out='out', err=b'err')"
+    assert str(cr) == repr_
+
+
+def test_capsysbinary(testdir: Testdir) -> None:
+    p1 = testdir.makepyfile(
+        """
+        def test(capsysbinary):
+            print("hello")
+            assert False, "trigger_failure"
+        """
+    )
+    result = testdir.runpytest(str(p1))
+    result.stdout.fnmatch_lines([
+        'E       assert False',
+        '*- Captured stdout call -*',
+        'hello',
+    ])
+    assert result.ret == 1
+
+
 class TestCaptureManager:
     def test_getmethod_default_no_fd(self, monkeypatch):
         from _pytest.capture import pytest_addoption