Merge merge branch

I suspect I don't yet know how to use git...  Surely I don't need two
merges to merge a contribution.

CHANGELOG

@@ -1,5 +1,9 @@
 2.8.0.dev (compared to 2.7.X)
 -----------------------------
+
+- Deal with capturing failures better so fewer exceptions get lost to
+  /dev/null.  Thanks David Szotten for the PR.
+
 - fix issue730: deprecate and warn about the --genscript option.
   Thanks Ronny Pfannschmidt for the report and Christian Pommranz for the PR.
 

_pytest/capture.py

@@ -86,8 +86,10 @@ class CaptureManager:
         self.deactivate_funcargs()
         cap = getattr(self, "_capturing", None)
         if cap is not None:
-            outerr = cap.readouterr()
-            cap.suspend_capturing(in_=in_)
+            try:
+                outerr = cap.readouterr()
+            finally:
+                cap.suspend_capturing(in_=in_)
             return outerr
 
     def activate_funcargs(self, pyfuncitem):

testing/test_capture.py

@@ -566,6 +566,25 @@ def test_capture_binary_output(testdir):
     result.assert_outcomes(passed=2)
 
 
+def test_error_during_readouterr(testdir):
+    """Make sure we suspend capturing if errors occurr during readouterr"""
+    testdir.makepyfile(pytest_xyz="""
+        from _pytest.capture import FDCapture
+        def bad_snap(self):
+            raise Exception('boom')
+        assert FDCapture.snap
+        FDCapture.snap = bad_snap
+    """)
+    result = testdir.runpytest_subprocess(
+        "-p", "pytest_xyz", "--version", syspathinsert=True
+    )
+    result.stderr.fnmatch_lines([
+        "*in bad_snap",
+        "    raise Exception('boom')",
+        "Exception: boom",
+    ])
+
+
 class TestTextIO:
     def test_text(self):
         f = capture.TextIO()