--pdb treats KeyboardInterrupt as exception

_pytest/debugging.py

@@ -16,7 +16,7 @@ def pytest_addoption(parser):
     group = parser.getgroup("general")
     group._addoption(
         '--pdb', dest="usepdb", action="store_true",
-        help="start the interactive Python debugger on errors.")
+        help="start the interactive Python debugger on errors or KeyboardInterrupt.")
     group._addoption(
         '--pdbcls', dest="usepdb_cls", metavar="modulename:classname",
         help="start a custom interactive Python debugger on errors. "

_pytest/runner.py

@@ -176,7 +176,8 @@ def check_interactive_exception(call, report):
 def call_runtest_hook(item, when, **kwds):
     hookname = "pytest_runtest_" + when
     ihook = getattr(item.ihook, hookname)
-    return CallInfo(lambda: ihook(item=item, **kwds), when=when)
+    return CallInfo(lambda: ihook(item=item, **kwds), when=when,
+                    treat_keyboard_interrupt_as_exception=item.config.getvalue("usepdb"))
 
 
 class CallInfo(object):
@@ -184,7 +185,7 @@ class CallInfo(object):
     #: None or ExceptionInfo object.
     excinfo = None
 
-    def __init__(self, func, when):
+    def __init__(self, func, when, treat_keyboard_interrupt_as_exception=False):
         #: context of invocation: one of "setup", "call",
         #: "teardown", "memocollect"
         self.when = when
@@ -192,6 +193,9 @@ class CallInfo(object):
         try:
             self.result = func()
         except KeyboardInterrupt:
+            if treat_keyboard_interrupt_as_exception:
+                self.excinfo = ExceptionInfo()
+            else:
                 self.stop = time()
                 raise
         except:  # noqa

changelog/3299.feature.rst

@@ -0,0 +1,2 @@
+The ``--pdb`` option now causes KeyboardInterrupt to enter the debugger, instead of stopping the test session.
+On python 2.7, hitting CTRL+C again exits the debugger. On python 3.2 and higher, use CTRL+D.

doc/en/usage.rst

@@ -152,9 +152,9 @@ allows one to drop into the PDB_ prompt via a command line option::
 
     pytest --pdb
 
-This will invoke the Python debugger on every failure.  Often you might
-only want to do this for the first failing test to understand a certain
-failure situation::
+This will invoke the Python debugger on every failure (or KeyboardInterrupt).
+Often you might only want to do this for the first failing test to understand
+a certain failure situation::
 
     pytest -x --pdb   # drop to PDB on first failure, then end test session
     pytest --pdb --maxfail=3  # drop to PDB for first three failures

testing/test_pdb.py

@@ -2,6 +2,7 @@ from __future__ import absolute_import, division, print_function
 import sys
 import platform
 import os
+import signal
 
 import _pytest._code
 from _pytest.debugging import SUPPORTS_BREAKPOINT_BUILTIN
@@ -114,6 +115,14 @@ class TestPDB(object):
         assert rep.failed
         assert len(pdblist) == 0
 
+    def test_pdb_on_KeyboardInterrupt(self, testdir, pdblist):
+        rep = runpdb_and_get_report(testdir, """
+            def test_func():
+                raise KeyboardInterrupt
+        """)
+        assert rep.failed
+        assert len(pdblist) == 1
+
     def test_pdb_interaction(self, testdir):
         p1 = testdir.makepyfile("""
             def test_1():