Improve quitting from pdb

Regarding tests: it merges ``test_pdb_interaction``,
``test_pdb_print_captured_stdout``, and
``test_pdb_print_captured_stderr`` into
``test_pdb_print_captured_stdout_and_stderr`` (clarity and performance,
especially since pexpect tests are slow).

changelog/4280.bugfix.rst

@@ -0,0 +1,3 @@
+Improve quitting from pdb, especially with ``--trace``.
+
+Using ``q[quit]`` after ``pdb.set_trace()`` will quit pytest also.

src/_pytest/debugging.py

@@ -118,6 +118,10 @@ class pytestPDB(object):
 
                 do_c = do_cont = do_continue
 
+                def set_quit(self):
+                    super(_PdbWrapper, self).set_quit()
+                    outcomes.exit("Quitting debugger")
+
                 def setup(self, f, tb):
                     """Suspend on setup().
 
@@ -210,8 +214,7 @@ def _enter_pdb(node, excinfo, rep):
     tw.sep(">", "entering PDB")
     tb = _postmortem_traceback(excinfo)
     rep._pdbshown = True
-    if post_mortem(tb):
+    post_mortem(tb)
-        outcomes.exit("Quitting debugger")
     return rep
 
 
@@ -242,4 +245,5 @@ def post_mortem(t):
     p = Pdb()
     p.reset()
     p.interaction(None, t)
-    return p.quitting
+    if p.quitting:
+        outcomes.exit("Quitting debugger")

src/_pytest/outcomes.py

@@ -49,13 +49,13 @@ class Failed(OutcomeException):
     __module__ = "builtins"
 
 
-class Exit(SystemExit):
+class Exit(Exception):
     """ raised for immediate program exits (no tracebacks/summaries)"""
 
     def __init__(self, msg="unknown reason", returncode=None):
         self.msg = msg
         self.returncode = returncode
-        SystemExit.__init__(self, msg)
+        super(Exit, self).__init__(msg)
 
 
 # exposed helper methods
@@ -63,7 +63,7 @@ class Exit(SystemExit):
 
 def exit(msg, returncode=None):
     """
-    Exit testing process as if SystemExit was triggered.
+    Exit testing process.
 
     :param str msg: message to display upon exit.
     :param int returncode: return code to be used when exiting pytest.

testing/test_pdb.py

@@ -147,29 +147,6 @@ class TestPDB(object):
         assert rep.failed
         assert len(pdblist) == 1
 
-    def test_pdb_interaction(self, testdir):
-        p1 = testdir.makepyfile(
-            """
-            def test_1():
-                i = 0
-                assert i == 1
-
-            def test_not_called_due_to_quit():
-                pass
-        """
-        )
-        child = testdir.spawn_pytest("--pdb %s" % p1)
-        child.expect(".*def test_1")
-        child.expect(".*i = 0")
-        child.expect("Pdb")
-        child.sendeof()
-        rest = child.read().decode("utf8")
-        assert "= 1 failed in" in rest
-        assert "def test_1" not in rest
-        assert "Exit: Quitting debugger" in rest
-        assert "PDB continue (IO-capturing resumed)" not in rest
-        self.flush(child)
-
     @staticmethod
     def flush(child):
         if platform.system() == "Darwin":
@@ -214,40 +191,32 @@ class TestPDB(object):
         child.sendeof()
         self.flush(child)
 
-    def test_pdb_print_captured_stdout(self, testdir):
+    def test_pdb_print_captured_stdout_and_stderr(self, testdir):
-        p1 = testdir.makepyfile(
-            """
-            def test_1():
-                print("get\\x20rekt")
-                assert False
-        """
-        )
-        child = testdir.spawn_pytest("--pdb %s" % p1)
-        child.expect("captured stdout")
-        child.expect("get rekt")
-        child.expect("Pdb")
-        child.sendeof()
-        rest = child.read().decode("utf8")
-        assert "1 failed" in rest
-        assert "get rekt" not in rest
-        self.flush(child)
-
-    def test_pdb_print_captured_stderr(self, testdir):
         p1 = testdir.makepyfile(
             """
             def test_1():
                 import sys
                 sys.stderr.write("get\\x20rekt")
+                print("get\\x20rekt")
                 assert False
+
+            def test_not_called_due_to_quit():
+                pass
         """
         )
         child = testdir.spawn_pytest("--pdb %s" % p1)
+        child.expect("captured stdout")
+        child.expect("get rekt")
         child.expect("captured stderr")
         child.expect("get rekt")
+        child.expect("traceback")
+        child.expect("def test_1")
         child.expect("Pdb")
         child.sendeof()
         rest = child.read().decode("utf8")
-        assert "1 failed" in rest
+        assert "Exit: Quitting debugger" in rest
+        assert "= 1 failed in" in rest
+        assert "def test_1" not in rest
         assert "get rekt" not in rest
         self.flush(child)
 
@@ -375,15 +344,17 @@ class TestPDB(object):
                 i = 0
                 print("hello17")
                 pytest.set_trace()
-                x = 3
+                i == 1
+                assert 0
         """
         )
         child = testdir.spawn_pytest(str(p1))
-        child.expect("test_1")
+        child.expect(r"test_1\(\)")
-        child.expect("x = 3")
+        child.expect("i == 1")
         child.expect("Pdb")
-        child.sendeof()
+        child.sendline("c")
         rest = child.read().decode("utf-8")
+        assert "AssertionError" in rest
         assert "1 failed" in rest
         assert "def test_1" in rest
         assert "hello17" in rest  # out is captured
@@ -398,13 +369,14 @@ class TestPDB(object):
                 print("hello17")
                 pytest.set_trace(header="== my_header ==")
                 x = 3
+                assert 0
         """
         )
         child = testdir.spawn_pytest(str(p1))
         child.expect("== my_header ==")
         assert "PDB set_trace" not in child.before.decode()
         child.expect("Pdb")
-        child.sendeof()
+        child.sendline("c")
         rest = child.read().decode("utf-8")
         assert "1 failed" in rest
         assert "def test_1" in rest
@@ -424,9 +396,9 @@ class TestPDB(object):
         child.expect("Pdb")
         child.sendeof()
         rest = child.read().decode("utf8")
-        assert "1 failed" in rest
+        assert "no tests ran" in rest
         assert "reading from stdin while output" not in rest
-        assert "BdbQuit" in rest
+        assert "BdbQuit" not in rest
         self.flush(child)
 
     def test_pdb_and_capsys(self, testdir):
@@ -518,6 +490,7 @@ class TestPDB(object):
                 print("hello18")
                 pytest.set_trace()
                 x = 4
+                assert 0
         """
         )
         child = testdir.spawn_pytest(str(p1))
@@ -530,11 +503,11 @@ class TestPDB(object):
         child.expect(r"PDB set_trace \(IO-capturing turned off\)")
         child.expect("x = 4")
         child.expect("Pdb")
-        child.sendeof()
+        child.sendline("c")
         child.expect("_ test_1 _")
         child.expect("def test_1")
-        child.expect("Captured stdout call")
         rest = child.read().decode("utf8")
+        assert "Captured stdout call" in rest
         assert "hello17" in rest  # out is captured
         assert "hello18" in rest  # out is captured
         assert "1 failed" in rest
@@ -795,7 +768,7 @@ class TestDebuggingBreakpoints(object):
         child.expect("Pdb")
         child.sendeof()
         rest = child.read().decode("utf8")
-        assert "1 failed" in rest
+        assert "Quitting debugger" in rest
         assert "reading from stdin while output" not in rest
         TestPDB.flush(child)
 
@@ -808,12 +781,13 @@ class TestDebuggingBreakpoints(object):
             import pdb
             def test_1():
                 pdb.set_trace()
+                assert 0
         """
         )
         child = testdir.spawn_pytest(str(p1))
         child.expect("test_1")
         child.expect("Pdb")
-        child.sendeof()
+        child.sendline("c")
         rest = child.read().decode("utf8")
         assert "1 failed" in rest
         assert "reading from stdin while output" not in rest
@@ -826,15 +800,29 @@ class TestTraceOption:
             """
             def test_1():
                 assert True
+
+            def test_2():
+                pass
+
+            def test_3():
+                pass
             """
         )
         child = testdir.spawn_pytest("--trace " + str(p1))
         child.expect("test_1")
         child.expect("Pdb")
-        child.sendeof()
+        child.sendline("c")
+        child.expect("test_2")
+        child.expect("Pdb")
+        child.sendline("c")
+        child.expect("test_3")
+        child.expect("Pdb")
+        child.sendline("q")
+        child.expect_exact("Exit: Quitting debugger")
         rest = child.read().decode("utf8")
-        assert "1 passed" in rest
+        assert "2 passed in" in rest
         assert "reading from stdin while output" not in rest
+        assert "Exit: Quitting debugger" in child.before.decode("utf8")
         TestPDB.flush(child)
 
 
@@ -863,3 +851,31 @@ def test_trace_after_runpytest(testdir):
     rest = child.read().decode("utf8")
     TestPDB.flush(child)
     assert child.exitstatus == 0, rest
+
+
+def test_quit_with_swallowed_SystemExit(testdir):
+    """Test that debugging's pytest_configure is re-entrant."""
+    p1 = testdir.makepyfile(
+        """
+        def call_pdb_set_trace():
+            __import__('pdb').set_trace()
+
+
+        def test_1():
+            try:
+                call_pdb_set_trace()
+            except SystemExit:
+                pass
+
+
+        def test_2():
+            pass
+    """
+    )
+    child = testdir.spawn_pytest(str(p1))
+    child.expect("Pdb")
+    child.sendline("q")
+    child.expect_exact("Exit: Quitting debugger")
+    rest = child.read().decode("utf8")
+    assert "no tests ran" in rest
+    TestPDB.flush(child)