Handle YANG binary type

As described in RFC7959, section 9.8.2, values of the ``binary``
built-in type are represented with the base64 encoding scheme.
Encode / decode from that scheme on serialise/deserialise, and
use native ``bytes`` type for Python representation.

pyangbind/lib/yangtypes.py

@@ -1370,76 +1370,3 @@ def __repr__(self):
 
     def __str__(self, encoding="ascii", errors="replace"):
         return str(self, encoding=encoding, errors=errors)
-
-
-def YANGBitsType(allowed_bits):
-    class YANGBits(set):
-        """Map the ``bits`` built-in type of YANG
-
-        From RFC 6020, 9.7:
-
-        > The bits built-in type represents a bit set. That is, a bits value
-        > is a set of flags identified by small integer position numbers
-        > starting at 0. Each bit number has an assigned name.
-        >
-        > ... In the canonical form, the bit values are separated by a single
-        > space character and they appear ordered by their position.
-
-        __init__ parses such a string, and __str__() prints the value as
-        above. In the Python model, the bits that are set are kept as a set
-        of strings.
-
-        Override the ``add()``, ``discard()`` and similar methods to set and
-        clear the bits, checking for legal values.
-
-        :param allowed_bits: dictionary of legal bit values and positions; it
-            is set when generating the YANG-Python type mapping, when
-            ``pyangbing.lib.pybing.build_elemtype`` recurses over the YANG model
-        """
-
-        _pybind_generated_by = "YANGBits"
-
-        def __init__(self, *args, **kwargs):
-            super().__init__()
-            self._allowed_bits = allowed_bits
-
-            if args:
-                value = args[0]
-                for bit in value.split():
-                    self.add(bit)
-
-        def _add_bit_definition(self, bit, position):
-            self._allowed_bits[bit] = position
-
-        # overwrite set methods to 1/ check for legal values and 2/ set the
-        # changed flag
-        def add(self, bit):
-            if bit not in self._allowed_bits:
-                raise ValueError(f"Bit value {bit} not valid, expected one of {self._allowed_bits}")
-            super().add(bit)
-            self._mchanged = True
-
-        def clear(self):
-            super().clear()
-            self._mchanged = True
-
-        def discard(self, bit):
-            if bit not in self._allowed_bits:
-                raise ValueError(f"Bit value {bit} not valid, expected one of {self._allowed_bits}")
-            super().discard(bit)
-            self._mchanged = True
-
-        def pop(self):
-            super().pop()
-            self._mchanged = True
-
-        def remove(self, bit):
-            super().remove(bit)
-            self._mchanged = True
-
-        def __str__(self, encoding="ascii", errors="replace"):
-            """Return bits as shown in JSON."""
-            sort_key = self._allowed_bits.__getitem__
-            return " ".join(sorted(self, key=sort_key))
-
-    return YANGBits

pyangbind/plugin/pybind.py

@@ -34,13 +34,7 @@
 
 import pyangbind.helpers.misc as misc_help
 from pyangbind.helpers.identity import IdentityStore
-from pyangbind.lib.yangtypes import (
-    RestrictedClassType,
-    YANGBool,
-    safe_name,
-    YANGBinary,
-    YANGBitsType,
-)
+from pyangbind.lib.yangtypes import RestrictedClassType, YANGBool, safe_name, YANGBinary
 
 # Python3 support
 if six.PY3:
@@ -329,7 +323,6 @@ def build_pybind(ctx, modules, fd):
         "YANGDynClass",
         "ReferenceType",
         "YANGBinary",
-        "YANGBitsType",
     ]
     for library in yangtypes_imports:
         ctx.pybind_common_hdr += "from pyangbind.lib.yangtypes import {}\n".format(library)