From 956b3aca97cadf4fd802b60607115d1276f62229 Mon Sep 17 00:00:00 2001
From: Anthony Sottile <asottile@umich.edu>
Date: Sun, 23 Sep 2018 18:39:50 -0700
Subject: [PATCH 1/2] Revert patching of breakpointhook as it appears to do
 nothing

---
 src/_pytest/debugging.py | 16 ----------------
 testing/test_pdb.py      |  8 +++++++-
 2 files changed, 7 insertions(+), 17 deletions(-)

diff --git a/src/_pytest/debugging.py b/src/_pytest/debugging.py
index f51dff373..717e4a27a 100644
--- a/src/_pytest/debugging.py
+++ b/src/_pytest/debugging.py
@@ -2,18 +2,10 @@
 from __future__ import absolute_import, division, print_function
 import pdb
 import sys
-import os
 from doctest import UnexpectedException
 
 from _pytest.config import hookimpl
 
-try:
-    from builtins import breakpoint  # noqa
-
-    SUPPORTS_BREAKPOINT_BUILTIN = True
-except ImportError:
-    SUPPORTS_BREAKPOINT_BUILTIN = False
-
 
 def pytest_addoption(parser):
     group = parser.getgroup("general")
@@ -51,20 +43,12 @@ def pytest_configure(config):
     if config.getvalue("usepdb"):
         config.pluginmanager.register(PdbInvoke(), "pdbinvoke")
 
-    # Use custom Pdb class set_trace instead of default Pdb on breakpoint() call
-    if SUPPORTS_BREAKPOINT_BUILTIN:
-        _environ_pythonbreakpoint = os.environ.get("PYTHONBREAKPOINT", "")
-        if _environ_pythonbreakpoint == "":
-            sys.breakpointhook = pytestPDB.set_trace
-
     old = (pdb.set_trace, pytestPDB._pluginmanager)
 
     def fin():
         pdb.set_trace, pytestPDB._pluginmanager = old
         pytestPDB._config = None
         pytestPDB._pdb_cls = pdb.Pdb
-        if SUPPORTS_BREAKPOINT_BUILTIN:
-            sys.breakpointhook = sys.__breakpointhook__
 
     pdb.set_trace = pytestPDB.set_trace
     pytestPDB._pluginmanager = config.pluginmanager
diff --git a/testing/test_pdb.py b/testing/test_pdb.py
index 246f514b4..2526873e3 100644
--- a/testing/test_pdb.py
+++ b/testing/test_pdb.py
@@ -4,9 +4,15 @@ import platform
 import os
 
 import _pytest._code
-from _pytest.debugging import SUPPORTS_BREAKPOINT_BUILTIN
 import pytest
 
+try:
+    breakpoint
+except NameError:
+    SUPPORTS_BREAKPOINT_BUILTIN = False
+else:
+    SUPPORTS_BREAKPOINT_BUILTIN = True
+
 
 _ENVIRON_PYTHONBREAKPOINT = os.environ.get("PYTHONBREAKPOINT", "")
 

From dbfb3ccc422fb7e8fd1c7db93b601a5610393e2d Mon Sep 17 00:00:00 2001
From: Anthony Sottile <asottile@umich.edu>
Date: Wed, 10 Oct 2018 10:46:09 -0700
Subject: [PATCH 2/2] Add changelog entry

---
 changelog/4028.trivial.rst | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 changelog/4028.trivial.rst

diff --git a/changelog/4028.trivial.rst b/changelog/4028.trivial.rst
new file mode 100644
index 000000000..2ec5f6306
--- /dev/null
+++ b/changelog/4028.trivial.rst
@@ -0,0 +1 @@
+Revert patching of ``sys.breakpointhook`` since it appears to do nothing.