py/objtype: Allow passing keyword arguments to native base __init__.

Allowing passing keyword arguments to a native base's __init__, i.e.
`make_new` in the C code.  Previously only positional arguments were
allowed.

The main trade-off in this commit is that every call to the native base's
`make_new` is now going to be preceded by a call to
`mp_map_init_fixed_table` even though most of what that does is unused and
instead it merely serves as a way to pass the number of keyword arguments.

Fixes issue #15465.

Signed-off-by: stijn <stijn@ignitron.net>

1 files changed, 29 insertions, 0 deletions

diff --git a/tests/basics/subclass_native_init.py b/tests/basics/subclass_native_init.py
index 38d2f23ac3..64167fa037 100644
--- a/tests/basics/subclass_native_init.py
+++ b/tests/basics/subclass_native_init.py
@@ -6,6 +6,35 @@ class L(list):
         super().__init__([a, b])
 print(L(2, 3))
 
+# with keyword arguments, with star arguments and without because those use different C calls
+class D(dict):
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+print(D())
+print(D([('a', 1)]))
+print(D([('a', 1)], a=2, b=3))
+print(D(a=2, b=3))
+
+class D(dict):
+    def __init__(self):
+        super().__init__()
+print(D())
+
+class D(dict):
+    def __init__(self):
+        super().__init__([])
+print(D())
+
+class D(dict):
+    def __init__(self):
+        super().__init__(a=1)
+print(D())
+
+class D(dict):
+    def __init__(self):
+        super().__init__([], a=1)
+print(D())
+
 # inherits implicitly from object
 class A:
     def __init__(self):