move MultiEnum to dotnet.util

dotnet/common.py

@@ -1,6 +1,5 @@
 import enum
 import math
-import collections
 from destruct import Type, Struct
 
 class CLIStreamType(enum.Enum):
@@ -187,43 +186,3 @@ class CLIStreamIndex(Type):
         else:
             size = 2
         return int.from_bytes(input.read(size), 'little')
-
-class MultiEnumMeta(type):
-    @classmethod
-    def __prepare__(mcls, name, bases, **kwargs):
-        return collections.OrderedDict()
-
-    def __new__(cls, name, bases, attrs, **kwargs):
-        parsers = {}
-        used = 0
-        for key, value in attrs.copy().items():
-            if isinstance(value, tuple):
-                if len(value) == 2:
-                    child, mask = value
-                elif len(value) == 3:
-                    child, offset, size = value
-                    mask = ((1 << size) - 1) << offset
-                if issubclass(child, enum.Enum):
-                    if mask is None:
-                        mask = ~used
-                    parsers[key] = (child, mask)
-                    used |= mask
-                    del attrs[key]
-
-        attrs['_parsers_'] = parsers
-        return super().__new__(cls, name, bases, attrs)
-
-class MultiEnum(metaclass=MultiEnumMeta):
-    def __init__(self, value: int):
-        for field, (child, mask) in self._parsers_.items():
-            setattr(self, field, child(value & mask))
-
-    def __str__(self):
-        return '{}({})'.format(self.__class__.__name__,
-            ', '.join('{}: {}'.format(n, getattr(self, n)) for n in self._parsers_)
-        )
-
-    def __repr__(self):
-        return '<{}({})>'.format(self.__class__.__name__,
-            ', '.join('{}: {!r}'.format(n, getattr(self, n)) for n in self._parsers_)
-        )

dotnet/tables.py

@@ -1,8 +1,8 @@
 import enum
 from destruct import Struct
 
+from .util import MultiEnum
 from .common import (
-    MultiEnum,
     CLIElementType, CLIStreamType, CLITableType,
     CLICodedToken, CLIStreamIndex, CLITableIndex, CLITableRange
 )

dotnet/types.py

@@ -2,7 +2,8 @@ import enum
 from itertools import zip_longest
 
 from destruct import parse, Type, Struct
-from .common import CLICodedToken, CLITableType, CLIElementType, MultiEnum
+from .util import MultiEnum
+from .common import CLICodedToken, CLITableType, CLIElementType
 
 
 

dotnet/util.py

@@ -0,0 +1,48 @@
+import inspect
+import collections
+import functools
+
+
+def cached_property(f):
+    return property(functools.lru_cache()(f))
+
+
+class MultiEnumMeta(type):
+    @classmethod
+    def __prepare__(mcls, name, bases, **kwargs):
+        return collections.OrderedDict()
+
+    def __new__(cls, name, bases, attrs, **kwargs):
+        parsers = {}
+        used = 0
+        for key, value in attrs.copy().items():
+            if isinstance(value, tuple):
+                if len(value) == 2:
+                    child, mask = value
+                elif len(value) == 3:
+                    child, offset, size = value
+                    mask = ((1 << size) - 1) << offset
+                if inspect.isclass(child):
+                    if mask is None:
+                        mask = ~used
+                    parsers[key] = (child, mask)
+                    used |= mask
+                    del attrs[key]
+
+        attrs['_parsers_'] = parsers
+        return super().__new__(cls, name, bases, attrs)
+
+class MultiEnum(metaclass=MultiEnumMeta):
+    def __init__(self, value: int):
+        for field, (child, mask) in self._parsers_.items():
+            setattr(self, field, child(value & mask))
+
+    def __str__(self):
+        return '{}({})'.format(self.__class__.__name__,
+            ', '.join('{}: {}'.format(n, getattr(self, n)) for n in self._parsers_)
+        )
+
+    def __repr__(self):
+        return '<{}({})>'.format(self.__class__.__name__,
+            ', '.join('{}: {!r}'.format(n, getattr(self, n)) for n in self._parsers_)
+        )