Fixed constructors for Multicodec, Multibase and Multihash.

It is now possible to construct objects by passing the arguments positionally, as already done in many of the examples.

Author: sg495

multiformats/__init__.py

@@ -15,7 +15,7 @@
     while :class:`~multiformats.cid.CID` is a class for Content IDentifiers.
 """
 
-__version__ = "0.2.0"
+__version__ = "0.2.1"
 
 from . import varint
 from . import multicodec

multiformats/multibase/__init__.py

@@ -54,21 +54,23 @@ class Multibase:
 
     __slots__ = ("__weakref__", "_name", "_code", "_status", "_description")
 
-    def __init__(self, *,
-                 name: str,
-                 code: str,
-                 status: str = "draft",
-                 description: str = ""
-                ):
+    def __new__(cls,
+                name: str,
+                code: str,
+                status: str = "draft",
+                description: str = ""
+                ) -> "Multibase":
         for arg in (name, code, status, description):
             validate(arg, str)
         name = Multibase._validate_name(name)
         code = Multibase.validate_code(code)
         status = Multibase._validate_status(status)
-        self._name = name
-        self._code = code
-        self._status = status
-        self._description = description
+        instance = super().__new__(cls)
+        instance._name = name
+        instance._code = code
+        instance._status = status
+        instance._description = description
+        return instance
 
     @staticmethod
     def _validate_name(name: Optional[str]) -> str:

multiformats/multicodec/__init__.py

@@ -58,24 +58,27 @@ class Multicodec:
 
     __slots__ = ("__weakref__", "_name", "_tag", "_code", "_status", "_description")
 
-    def __init__(self, *,
-                 name: str,
-                 tag: str,
-                 code: Union[int, str],
-                 status: str = "draft",
-                 description: str = ""
-                ):
+    def __new__(cls,
+                name: str,
+                tag: str,
+                code: Union[int, str],
+                status: str = "draft",
+                description: str = ""
+               ) -> "Multicodec":
+        # pylint: disable = too-many-arguments
         for arg in (name, tag, status, description):
             validate(arg, str)
         validate(code, Union[int, str])
         name = Multicodec._validate_name(name)
         code = Multicodec.validate_code(code)
         status = Multicodec._validate_status(status)
-        self._name = name
-        self._tag = tag
-        self._code = code
-        self._status = status
-        self._description = description
+        instance = super().__new__(cls)
+        instance._name = name
+        instance._tag = tag
+        instance._code = code
+        instance._status = status
+        instance._description = description
+        return instance
 
     @staticmethod
     def _validate_name(name: str) -> str:

multiformats/multihash/__init__.py

@@ -43,7 +43,7 @@ class Multihash:
 
     __slots__ = ("__weakref__", "_codec", "_implementation")
 
-    def __new__(cls, *, codec: Union[str, int, Multicodec]) -> "Multihash":
+    def __new__(cls, codec: Union[str, int, Multicodec]) -> "Multihash":
         # check that the codec exists:
         if isinstance(codec, str):
             codec = multicodec.get(codec)

tox.ini

@@ -15,6 +15,7 @@ deps =
     pyskein
     mmh3
     pycryptodomex
+    multiformats_config
 
 setenv =
     PYTHONPATH = {toxinidir}