python · remilapeyre · Jan 15, 2019 · Jan 16, 2019 · Jan 16, 2019 · Jan 16, 2019
diff --git a/Doc/library/exceptions.rst b/Doc/library/exceptions.rst
@@ -87,6 +87,10 @@ The following exceptions are used mostly as base classes for other exceptions.
       assign a special meaning to the elements of this tuple, while others are
       usually called only with a single string giving an error message.
 
+   .. attribute:: kwargs
+
+      The dictionnary of keyword arguments given to the exception constructor.
+
    .. method:: with_traceback(tb)
 
       This method sets *tb* as the new traceback for the exception and returns

diff --git a/Include/cpython/pyerrors.h b/Include/cpython/pyerrors.h
@@ -10,7 +10,7 @@ extern "C" {
 
 /* PyException_HEAD defines the initial segment of every exception class. */
 #define PyException_HEAD PyObject_HEAD PyObject *dict;\
-             PyObject *args; PyObject *traceback;\
+             PyObject *args; PyObject *kwargs; PyObject *traceback;\
              PyObject *context; PyObject *cause;\
              char suppress_context;
 

@@ -439,16 +439,15 @@ def testAttributes(self):
                                      value, expected[checkArgName]))
 
                 # test for pickling support
-                for p in [pickle]:
-                    for protocol in range(p.HIGHEST_PROTOCOL + 1):
-                        s = p.dumps(e, protocol)
-                        new = p.loads(s)
-                        for checkArgName in expected:
-                            got = repr(getattr(new, checkArgName))
-                            want = repr(expected[checkArgName])
-                            self.assertEqual(got, want,
-                                             'pickled "%r", attribute "%s' %
-                                             (e, checkArgName))
+                for protocol in range(pickle.HIGHEST_PROTOCOL + 1):
+                    s = pickle.dumps(e, protocol)
+                    new = pickle.loads(s)
+                    for checkArgName in expected:
+                        got = repr(getattr(new, checkArgName))
+                        want = repr(expected[checkArgName])
+                        self.assertEqual(got, want,
+                                            'pickled "%r", attribute "%s"' %
+                                            (e, checkArgName))
 
     def testWithTraceback(self):
         try:
@@ -1299,6 +1298,43 @@ def g():
                 next(i)
                 next(i)
 
+    def test_get_kwargs(self):
+        self.assertEqual(BaseException().kwargs, {})
+        self.assertEqual(NaiveException(x=1).kwargs, {'x': 1})
+
+    def test_set_kwargs(self):
+        b = BaseException()
+        b.kwargs = {'x': 1}
+        self.assertEqual(b.kwargs, {'x': 1})
+
+        b = NaiveException(x=1)
+        b.kwargs = {'x': 2}
+        self.assertEqual(b.kwargs, {'x': 2})
+
+    def test_del_args_kwargs(self):
+        b = BaseException()
+
+        with self.assertRaisesRegex(TypeError, "args may not be deleted"):
+            del b.args
+
+        with self.assertRaisesRegex(TypeError, "kwargs may not be deleted"):
+            del b.kwargs
+
+    def test_repr(self):
+        class MixedArgsKwargs(Exception):
+            def __init__(*args, **kwargs):
+                pass
+
+        self.assertEqual(repr(BaseException()), "BaseException()")
+        self.assertEqual(repr(BaseException(1)), "BaseException(1)")
+        self.assertEqual(repr(NaiveException(1)), "NaiveException(1)")
+        self.assertEqual(repr(NaiveException(x=1)), "NaiveException(x=1)")
+        self.assertEqual(repr(MixedArgsKwargs(1, b=2)), "MixedArgsKwargs(1, b=2)")
+
+        class NoKwargs(Exception):
+            def __init__(self, foo,):
+                self.args = (foo,)
+
 
 class ImportErrorTests(unittest.TestCase):
 
@@ -1376,6 +1412,19 @@ def test_copy_pickle(self):
                 self.assertEqual(exc.name, orig.name)
                 self.assertEqual(exc.path, orig.path)
 
+    def test_pickle_overriden_init(self):
+        # Issue #27015
+        for proto in range(pickle.HIGHEST_PROTOCOL + 1):
+            orig = NaiveException(x='foo')
+            if proto in (0, 1):
+                # Pickling excpetions keyword arguments is not supported for
+                # protocol 0 and 1
+                with self.assertRaises(TypeError):
+                    pickle.loads(pickle.dumps(orig, proto))
+            else:
+                exc = pickle.loads(pickle.dumps(orig, proto))
+                self.assertEqual(orig.x, exc.x)
+
 
 if __name__ == '__main__':
     unittest.main()
@@ -18,6 +18,7 @@
 import threading
 import gc
 import textwrap
+import pickle
 from test.support import FakePath
 
 try:
@@ -1690,6 +1691,14 @@ def test_CalledProcessError_str_non_zero(self):
         error_string = str(err)
         self.assertIn("non-zero exit status 2.", error_string)
 
+    def test_CalledProcessError_picklable(self):
+        # Issue #27015
+        err = subprocess.CalledProcessError(returncode=2, cmd='foo')
+        for proto in range(pickle.HIGHEST_PROTOCOL + 1):
+            new = pickle.loads(pickle.dumps(err, proto))
+            self.assertEqual(err.returncode, new.returncode)
+            self.assertEqual(err.cmd, new.cmd)
+
     def test_preexec(self):
         # DISCLAIMER: Setting environment variables is *not* a good use
         # of a preexec_fn.  This is merely a test.

diff --git a/Lib/test/test_sys.py b/Lib/test/test_sys.py
@@ -1004,13 +1004,13 @@ def inner():
         class C(object): pass
         check(C.__dict__, size('P'))
         # BaseException
-        check(BaseException(), size('5Pb'))
+        check(BaseException(), size('6Pb'))
         # UnicodeEncodeError
-        check(UnicodeEncodeError("", "", 0, 0, ""), size('5Pb 2P2nP'))
+        check(UnicodeEncodeError("", "", 0, 0, ""), size('6Pb 2P2nP'))
         # UnicodeDecodeError
-        check(UnicodeDecodeError("", b"", 0, 0, ""), size('5Pb 2P2nP'))
+        check(UnicodeDecodeError("", b"", 0, 0, ""), size('6Pb 2P2nP'))
         # UnicodeTranslateError
-        check(UnicodeTranslateError("", 0, 1, ""), size('5Pb 2P2nP'))
+        check(UnicodeTranslateError("", 0, 1, ""), size('6Pb 2P2nP'))
         # ellipses
         check(Ellipsis, size(''))
         # EncodingMap

diff --git a/Misc/NEWS.d/next/Core and Builtins/2019-01-16-15-07-10.bpo-27015.UOjO5h.rst b/Misc/NEWS.d/next/Core and Builtins/2019-01-16-15-07-10.bpo-27015.UOjO5h.rst
@@ -0,0 +1,3 @@
+Exceptions now save the keyword arguments given to their constructor in their
+``kwargs`` attribute.  Exceptions with overridden ``__init__`` and using keyword
+arguments are now picklable.  Contributed by Rémi Lapeyre.