(improvement) remove support for protocols <3 from cython files

cassandra/deserializers.pyx

@@ -208,15 +208,9 @@ cdef class _DesSingleParamType(_DesParameterizedType):
 
 cdef class DesListType(_DesSingleParamType):
     cdef deserialize(self, Buffer *buf, int protocol_version):
-        cdef uint16_t v2_and_below = 2
-        cdef int32_t v3_and_above = 3
 
-        if protocol_version >= 3:
-            result = _deserialize_list_or_set[int32_t](
-                v3_and_above, buf, protocol_version, self.deserializer)
-        else:
-            result = _deserialize_list_or_set[uint16_t](
-                v2_and_below, buf, protocol_version, self.deserializer)
+        result = _deserialize_list_or_set(
+            buf, protocol_version, self.deserializer)
 
         return result
 
@@ -225,60 +219,49 @@ cdef class DesSetType(DesListType):
         return util.sortedset(DesListType.deserialize(self, buf, protocol_version))
 
 
-ctypedef fused itemlen_t:
-    uint16_t # protocol <= v2
-    int32_t  # protocol >= v3
-
-cdef list _deserialize_list_or_set(itemlen_t dummy_version,
-                                   Buffer *buf, int protocol_version,
+cdef list _deserialize_list_or_set(Buffer *buf, int protocol_version,
                                    Deserializer deserializer):
     """
     Deserialize a list or set.
-
-    The 'dummy' parameter is needed to make fused types work, so that
-    we can specialize on the protocol version.
     """
     cdef Buffer itemlen_buf
     cdef Buffer elem_buf
 
-    cdef itemlen_t numelements
+    cdef int32_t numelements
     cdef int offset
     cdef list result = []
 
-    _unpack_len[itemlen_t](buf, 0, &numelements)
-    offset = sizeof(itemlen_t)
+    _unpack_len(buf, 0, &numelements)
+    offset = sizeof(int32_t)
     protocol_version = max(3, protocol_version)
     for _ in range(numelements):
-        subelem[itemlen_t](buf, &elem_buf, &offset, dummy_version)
+        subelem(buf, &elem_buf, &offset)
         result.append(from_binary(deserializer, &elem_buf, protocol_version))
 
     return result
 
 
 cdef inline int subelem(
-        Buffer *buf, Buffer *elem_buf, int* offset, itemlen_t dummy) except -1:
+        Buffer *buf, Buffer *elem_buf, int* offset) except -1:
     """
     Read the next element from the buffer: first read the size (in bytes) of the
     element, then fill elem_buf with a newly sliced buffer of this size (and the
     right offset).
     """
-    cdef itemlen_t elemlen
+    cdef int32_t elemlen
 
-    _unpack_len[itemlen_t](buf, offset[0], &elemlen)
-    offset[0] += sizeof(itemlen_t)
+    _unpack_len(buf, offset[0], &elemlen)
+    offset[0] += sizeof(int32_t)
     slice_buffer(buf, elem_buf, offset[0], elemlen)
     offset[0] += elemlen
     return 0
 
 
-cdef int _unpack_len(Buffer *buf, int offset, itemlen_t *output) except -1:
+cdef int _unpack_len(Buffer *buf, int offset, int32_t *output) except -1:
     cdef Buffer itemlen_buf
-    slice_buffer(buf, &itemlen_buf, offset, sizeof(itemlen_t))
+    slice_buffer(buf, &itemlen_buf, offset, sizeof(int32_t))
 
-    if itemlen_t is uint16_t:
-        output[0] = unpack_num[uint16_t](&itemlen_buf)
-    else:
-        output[0] = unpack_num[int32_t](&itemlen_buf)
+    output[0] = unpack_num[int32_t](&itemlen_buf)
 
     return 0
 
@@ -295,42 +278,33 @@ cdef class DesMapType(_DesParameterizedType):
         self.val_deserializer = self.deserializers[1]
 
     cdef deserialize(self, Buffer *buf, int protocol_version):
-        cdef uint16_t v2_and_below = 0
-        cdef int32_t v3_and_above = 0
         key_type, val_type = self.cqltype.subtypes
 
-        if protocol_version >= 3:
-            result = _deserialize_map[int32_t](
-                v3_and_above, buf, protocol_version,
-                self.key_deserializer, self.val_deserializer,
-                key_type, val_type)
-        else:
-            result = _deserialize_map[uint16_t](
-                v2_and_below, buf, protocol_version,
-                self.key_deserializer, self.val_deserializer,
-                key_type, val_type)
+        result = _deserialize_map(
+            buf, protocol_version,
+            self.key_deserializer, self.val_deserializer,
+            key_type, val_type)
 
         return result
 
 
-cdef _deserialize_map(itemlen_t dummy_version,
-                      Buffer *buf, int protocol_version,
+cdef _deserialize_map(Buffer *buf, int protocol_version,
                       Deserializer key_deserializer, Deserializer val_deserializer,
                       key_type, val_type):
     cdef Buffer key_buf, val_buf
     cdef Buffer itemlen_buf
 
-    cdef itemlen_t numelements
+    cdef int32_t numelements
     cdef int offset
     cdef list result = []
 
-    _unpack_len[itemlen_t](buf, 0, &numelements)
-    offset = sizeof(itemlen_t)
+    _unpack_len(buf, 0, &numelements)
+    offset = sizeof(int32_t)
     themap = util.OrderedMapSerializedKey(key_type, protocol_version)
     protocol_version = max(3, protocol_version)
     for _ in range(numelements):
-        subelem[itemlen_t](buf, &key_buf, &offset, dummy_version)
-        subelem[itemlen_t](buf, &val_buf, &offset, numelements)
+        subelem(buf, &key_buf, &offset)
+        subelem(buf, &val_buf, &offset)
         key = from_binary(key_deserializer, &key_buf, protocol_version)
         val = from_binary(val_deserializer, &val_buf, protocol_version)
         themap._insert_unchecked(key, to_bytes(&key_buf), val)