Do not assume that binary addresses are valid unicode

On lookup failure we would previously assume that binary addresses are
valid unicode when constructing exception messages. With
python/cpython#105375 which appeared e.g., in python-3.11.9 this starts
to cause failures as invalid unicode is now more consistently rejected; e.g., in
the test `pysubnettree.lookup` we construct a binary address `1.3.3.255`
which corresponds to `b'\x01\x03\x03\xff'` which is not valid unicode.

With this patch we set messages for `KeyError` from a `bytes` object
instead of a `str`, so that user's see e.g.,

    KeyError: b'1:3:3::3'

instead of the previous

    KeyError: '1:3:3::3'

This should still provide all the information necessary while working
with our interface which allows both `str` and `bytes` inputs.

The changes to `SubnetTree_wrap.cc` are generated automatically with
swig-3.0.12.

(cherry picked from commit d61edb0)

Author: bbannier

SubnetTree_wrap.cc

@@ -3457,7 +3457,7 @@ SWIGINTERN PyObject *SubnetTree___getitem__(SubnetTree *self,char *cidr,int size
 
            PyObject* data = self->lookup(cidr, size);
            if ( ! data ) {
-               PyErr_SetString(PyExc_KeyError, cidr);
+               PyErr_SetObject(PyExc_KeyError, PyBytes_FromStringAndSize(cidr, size));
                return 0;
            }
 

include/SubnetTree.h

@@ -147,7 +147,7 @@ class SubnetTree
 
            PyObject* data = self->lookup(cidr, size);
            if ( ! data ) {
-               PyErr_SetString(PyExc_KeyError, cidr);
+               PyErr_SetObject(PyExc_KeyError, PyBytes_FromStringAndSize(cidr, size));
                return 0;
            }
 

testing/pysubnettree/lookup.test

@@ -40,8 +40,11 @@ def do_tests(binarymode):
     try:
         if t[v4("1.3.3.255")]:  pass
         testcase(False, "lookup should throw exception")
-    except KeyError:
-        pass
+    except KeyError as e:
+        # We expect a `KeyError` which reports the key. Since above address
+        # encodes to invalid unicode we'd expect to see the raw bytes as error
+        # message in binary mode.
+        assert str(e) == r"b'\x01\x03\x03\xff'" if binarymode else r"b'1.3.3.255'"
 
     try:
         if t[v6("1:3:3::3")]:  pass