features: make features implement __lt__

capa/features/basicblock.py

@@ -20,7 +20,7 @@ class BasicBlock(Feature):
         return ""
 
     def freeze_serialize(self):
-        return (self.__class__.__name__, [])
+        return (self.__class__.__name__, ())
 
     @classmethod
     def freeze_deserialize(cls, args):

capa/features/common.py

@@ -107,6 +107,9 @@ class Feature(abc.ABC):
     def __hash__(self):
         return hash((self.name, self.value))
 
+    def __lt__(self, other):
+        return self.freeze_serialize() < other.freeze_serialize()
+
     def __eq__(self, other):
         return self.name == other.name and self.value == other.value
 
@@ -137,7 +140,7 @@ class Feature(abc.ABC):
         return Result(self in ctx, self, [], locations=ctx.get(self, set()))
 
     def freeze_serialize(self):
-        return (self.__class__.__name__, [self.value])
+        return (self.__class__.__name__, (self.value, ))
 
     @classmethod
     def freeze_deserialize(cls, args):
@@ -374,7 +377,7 @@ class Bytes(Feature):
         return hex_string(bytes_to_str(self.value))
 
     def freeze_serialize(self):
-        return (self.__class__.__name__, [bytes_to_str(self.value).upper()])
+        return (self.__class__.__name__, (bytes_to_str(self.value).upper(), ))
 
     @classmethod
     def freeze_deserialize(cls, args):

capa/features/insn.py

@@ -68,7 +68,7 @@ class _Operand(Feature, abc.ABC):
         return super().__eq__(other) and self.index == other.index
 
     def freeze_serialize(self):
-        return (self.__class__.__name__, [self.index, self.value])
+        return (self.__class__.__name__, (self.index, self.value))
 
 
 class OperandNumber(_Operand):

capa/render/vverbose.py

@@ -15,7 +15,6 @@ import capa.features.common
 import capa.render.result_document as rd
 from capa.rules import RuleSet
 from capa.engine import MatchResults
-from capa.features.freeze import deserialize_address
 
 
 def render_locations(ostream, match):

scripts/show-capabilities-by-function.py

@@ -62,8 +62,8 @@ import capa.engine
 import capa.helpers
 import capa.features
 import capa.exceptions
-import capa.render.verbose
 import capa.render.utils as rutils
+import capa.render.verbose
 import capa.features.freeze
 import capa.render.result_document as rd
 from capa.helpers import get_file_taste