pyln.proto.message: more mypy fixes.

This includes some real bugfixes, since it noticed some places we were
being loose with different types!

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

contrib/pyln-proto/Makefile

@@ -17,7 +17,7 @@ check-flake8:
 
 # mypy . does not recurse.  I have no idea why...
 check-mypy:
-	mypy --ignore-missing-imports `find * -name '*.py'`
+	mypy --ignore-missing-imports `find pyln/proto/message/ -name '*.py'`
 
 $(SDIST_FILE):
 	python3 setup.py sdist

contrib/pyln-proto/pyln/proto/message/array_types.py

@@ -1,8 +1,8 @@
 from .fundamental_types import FieldType, IntegerType, split_field
-from typing import List, Optional, Dict, Tuple, TYPE_CHECKING, Any, Union
+from typing import List, Optional, Dict, Tuple, TYPE_CHECKING, Any, Union, cast
 from io import BufferedIOBase
 if TYPE_CHECKING:
-    from .message import SubtypeType, TlvStreamType
+    from .message import SubtypeType, TlvMessageType, MessageTypeField
 
 
 class ArrayType(FieldType):
@@ -98,7 +98,7 @@ class SizedArrayType(ArrayType):
 class EllipsisArrayType(ArrayType):
     """This is used for ... fields at the end of a tlv: the array ends
 when the tlv ends"""
-    def __init__(self, tlv: 'TlvStreamType', name: str, elemtype: FieldType):
+    def __init__(self, tlv: 'TlvMessageType', name: str, elemtype: FieldType):
         super().__init__(tlv, name, elemtype)
 
     def read(self, io_in: BufferedIOBase, otherfields: Dict[str, Any]) -> List[Any]:
@@ -119,13 +119,13 @@ class LengthFieldType(FieldType):
         super().__init__(inttype.name)
         self.underlying_type = inttype
         # You can be length for more than one field!
-        self.len_for: List[DynamicArrayType] = []
+        self.len_for: List['MessageTypeField'] = []
 
     def is_optional(self) -> bool:
         """This field value is always implies, never specified directly"""
         return True
 
-    def add_length_for(self, field: 'DynamicArrayType') -> None:
+    def add_length_for(self, field: 'MessageTypeField') -> None:
         assert isinstance(field.fieldtype, DynamicArrayType)
         self.len_for.append(field)
 
@@ -160,7 +160,7 @@ class LengthFieldType(FieldType):
 they're implied by the length of other fields"""
         return ''
 
-    def read(self, io_in: BufferedIOBase, otherfields: Dict[str, Any]) -> None:
+    def read(self, io_in: BufferedIOBase, otherfields: Dict[str, Any]) -> Optional[int]:
         """We store this, but it'll be removed from the fields as soon as it's used (i.e. by DynamicArrayType's val_from_bin)"""
         return self.underlying_type.read(io_in, otherfields)
 
@@ -186,11 +186,11 @@ they're implied by the length of other fields"""
 
 class DynamicArrayType(ArrayType):
     """This is used for arrays where another field controls the size"""
-    def __init__(self, outer: 'SubtypeType', name: str, elemtype: FieldType, lenfield: LengthFieldType):
+    def __init__(self, outer: 'SubtypeType', name: str, elemtype: FieldType, lenfield: 'MessageTypeField'):
         super().__init__(outer, name, elemtype)
         assert type(lenfield.fieldtype) is LengthFieldType
         self.lenfield = lenfield
 
     def read(self, io_in: BufferedIOBase, otherfields: Dict[str, Any]) -> List[Any]:
         return super().read_arr(io_in, otherfields,
-                                self.lenfield.fieldtype._maybe_calc_value(self.lenfield.name, otherfields))
+                                cast(LengthFieldType, self.lenfield.fieldtype)._maybe_calc_value(self.lenfield.name, otherfields))

contrib/pyln-proto/pyln/proto/message/fundamental_types.py

@@ -59,6 +59,15 @@ These are further specialized.
     def val_to_str(self, v: Any, otherfields: Dict[str, Any]) -> str:
         raise NotImplementedError()
 
+    def val_from_str(self, s: str) -> Tuple[Any, str]:
+        raise NotImplementedError()
+
+    def write(self, io_out: BufferedIOBase, v: Any, otherfields: Dict[str, Any]) -> None:
+        raise NotImplementedError()
+
+    def read(self, io_in: BufferedIOBase, otherfields: Dict[str, Any]) -> Any:
+        raise NotImplementedError()
+
     def val_to_py(self, v: Any, otherfields: Dict[str, Any]) -> Any:
         """Convert to a python object: for simple fields, this means a string"""
         return self.val_to_str(v, otherfields)
@@ -83,7 +92,7 @@ class IntegerType(FieldType):
         a, b = split_field(s)
         return int(a), b
 
-    def val_to_py(self, v: Any, otherfields: Dict[str, Any]) -> int:
+    def val_to_py(self, v: Any, otherfields: Dict[str, Any]) -> Any:
         """Convert to a python object: for integer fields, this means an int"""
         return int(v)
 
@@ -240,7 +249,7 @@ class BigSizeType(FieldType):
         return int(v)
 
 
-def fundamental_types():
+def fundamental_types() -> List[FieldType]:
     # From 01-messaging.md#fundamental-types:
     return [IntegerType('byte', 1, 'B'),
             IntegerType('u16', 2, '>H'),

contrib/pyln-proto/pyln/proto/message/message.py

@@ -1,10 +1,10 @@
 import struct
 from io import BufferedIOBase, BytesIO
-from .fundamental_types import fundamental_types, BigSizeType, split_field, try_unpack, FieldType
+from .fundamental_types import fundamental_types, BigSizeType, split_field, try_unpack, FieldType, IntegerType
 from .array_types import (
     SizedArrayType, DynamicArrayType, LengthFieldType, EllipsisArrayType
 )
-from typing import Dict, List, Optional, Tuple, Any, Union, cast
+from typing import Dict, List, Optional, Tuple, Any, Union, Callable, cast
 
 
 class MessageNamespace(object):
@@ -12,7 +12,7 @@ class MessageNamespace(object):
 domain, such as within a given BOLT"""
     def __init__(self, csv_lines: List[str] = []):
         self.subtypes: Dict[str, SubtypeType] = {}
-        self.fundamentaltypes: Dict[str, SubtypeType] = {}
+        self.fundamentaltypes: Dict[str, FieldType] = {}
         self.tlvtypes: Dict[str, TlvStreamType] = {}
         self.messagetypes: Dict[str, MessageType] = {}
 
@@ -28,27 +28,35 @@ domain, such as within a given BOLT"""
         for v in other.subtypes.values():
             ret.add_subtype(v)
         ret.tlvtypes = self.tlvtypes.copy()
-        for v in other.tlvtypes.values():
-            ret.add_tlvtype(v)
+        for tlv in other.tlvtypes.values():
+            ret.add_tlvtype(tlv)
         ret.messagetypes = self.messagetypes.copy()
         for v in other.messagetypes.values():
             ret.add_messagetype(v)
         return ret
 
+    def _check_unique(self, name: str) -> None:
+        """Raise an exception if name already used"""
+        funtype = self.get_fundamentaltype(name)
+        if funtype:
+            raise ValueError('Already have {}'.format(funtype))
+        subtype = self.get_subtype(name)
+        if subtype:
+            raise ValueError('Already have {}'.format(subtype))
+        tlvtype = self.get_tlvtype(name)
+        if tlvtype:
+            raise ValueError('Already have {}'.format(tlvtype))
+
     def add_subtype(self, t: 'SubtypeType') -> None:
-        prev = self.get_type(t.name)
-        if prev:
-            raise ValueError('Already have {}'.format(prev))
+        self._check_unique(t.name)
         self.subtypes[t.name] = t
 
-    def add_fundamentaltype(self, t: 'SubtypeType') -> None:
-        assert not self.get_type(t.name)
+    def add_fundamentaltype(self, t: FieldType) -> None:
+        self._check_unique(t.name)
         self.fundamentaltypes[t.name] = t
 
     def add_tlvtype(self, t: 'TlvStreamType') -> None:
-        prev = self.get_type(t.name)
-        if prev:
-            raise ValueError('Already have {}'.format(prev))
+        self._check_unique(t.name)
         self.tlvtypes[t.name] = t
 
     def add_messagetype(self, m: 'MessageType') -> None:
@@ -70,7 +78,7 @@ domain, such as within a given BOLT"""
                 return m
         return None
 
-    def get_fundamentaltype(self, name: str) -> Optional['SubtypeType']:
+    def get_fundamentaltype(self, name: str) -> Optional[FieldType]:
         if name in self.fundamentaltypes:
             return self.fundamentaltypes[name]
         return None
@@ -85,14 +93,6 @@ domain, such as within a given BOLT"""
             return self.tlvtypes[name]
         return None
 
-    def get_type(self, name: str) -> Optional['SubtypeType']:
-        t = self.get_fundamentaltype(name)
-        if t is None:
-            t = self.get_subtype(name)
-        if t is None:
-            t = self.get_tlvtype(name)
-        return t
-
     def load_csv(self, lines: List[str]) -> None:
         """Load a series of comma-separate-value lines into the namespace"""
         vals: Dict[str, List[List[str]]] = {'msgtype': [],
@@ -152,23 +152,22 @@ class MessageTypeField(object):
         return self.full_name
 
 
-class SubtypeType(object):
+class SubtypeType(FieldType):
     """This defines a 'subtype' in BOLT-speak.  It consists of fields of
-other types.  Since 'msgtype' and 'tlvtype' are almost identical, they
-inherit from this too.
+other types.  Since 'msgtype' is almost identical, it inherits from this too.
 
     """
     def __init__(self, name: str):
-        self.name = name
-        self.fields: List[FieldType] = []
+        super().__init__(name)
+        self.fields: List[MessageTypeField] = []
 
-    def find_field(self, fieldname: str):
+    def find_field(self, fieldname: str) -> Optional[MessageTypeField]:
         for f in self.fields:
             if f.name == fieldname:
                 return f
         return None
 
-    def add_field(self, field: FieldType):
+    def add_field(self, field: MessageTypeField) -> None:
         if self.find_field(field.name):
             raise ValueError("{}: duplicate field {}".format(self, field))
         self.fields.append(field)
@@ -192,12 +191,16 @@ inherit from this too.
                              .format(parts))
         return SubtypeType(parts[0])
 
-    def _field_from_csv(self, namespace: MessageNamespace, parts: List[str], ellipsisok=False, option: str = None) -> MessageTypeField:
+    def _field_from_csv(self, namespace: MessageNamespace, parts: List[str], option: str = None) -> MessageTypeField:
         """Takes msgdata/subtypedata after first two fields
         e.g. [...]timestamp_node_id_1,u32,
 
         """
-        basetype = namespace.get_type(parts[1])
+        basetype = namespace.get_fundamentaltype(parts[1])
+        if basetype is None:
+            basetype = namespace.get_subtype(parts[1])
+        if basetype is None:
+            basetype = namespace.get_tlvtype(parts[1])
         if basetype is None:
             raise ValueError('Unknown type {}'.format(parts[1]))
 
@@ -206,7 +209,8 @@ inherit from this too.
             lenfield = self.find_field(parts[2])
             if lenfield is not None:
                 # If we didn't know that field was a length, we do now!
-                if type(lenfield.fieldtype) is not LengthFieldType:
+                if not isinstance(lenfield.fieldtype, LengthFieldType):
+                    assert isinstance(lenfield.fieldtype, IntegerType)
                     lenfield.fieldtype = LengthFieldType(lenfield.fieldtype)
                 field = MessageTypeField(self.name, parts[0],
                                          DynamicArrayType(self,
@@ -215,7 +219,9 @@ inherit from this too.
                                                           lenfield),
                                          option)
                 lenfield.fieldtype.add_length_for(field)
-            elif ellipsisok and parts[2] == '...':
+            elif parts[2] == '...':
+                # ... is only valid for a TLV.
+                assert isinstance(self, TlvMessageType)
                 field = MessageTypeField(self.name, parts[0],
                                          EllipsisArrayType(self,
                                                            parts[0], basetype),
@@ -264,8 +270,10 @@ inherit from this too.
             raise ValueError("Unknown fields specified: {}".format(unknown))
 
         for f in defined.difference(have):
-            if not f.fieldtype.is_optional():
-                raise ValueError("Missing value for {}".format(f))
+            field = self.find_field(f)
+            assert field
+            if not field.fieldtype.is_optional():
+                raise ValueError("Missing value for {}".format(field))
 
     def val_to_str(self, v: Dict[str, Any], otherfields: Dict[str, Any]) -> str:
         self._raise_if_badvals(v)
@@ -273,6 +281,7 @@ inherit from this too.
         sep = ''
         for fname, val in v.items():
             field = self.find_field(fname)
+            assert field
             s += sep + fname + '=' + field.fieldtype.val_to_str(val, otherfields)
             sep = ','
 
@@ -281,16 +290,19 @@ inherit from this too.
     def val_to_py(self, val: Dict[str, Any], otherfields: Dict[str, Any]) -> Dict[str, Any]:
         ret: Dict[str, Any] = {}
         for k, v in val.items():
-            ret[k] = self.find_field(k).fieldtype.val_to_py(v, val)
+            field = self.find_field(k)
+            assert field
+            ret[k] = field.fieldtype.val_to_py(v, val)
         return ret
 
     def write(self, io_out: BufferedIOBase, v: Dict[str, Any], otherfields: Dict[str, Any]) -> None:
         self._raise_if_badvals(v)
         for fname, val in v.items():
             field = self.find_field(fname)
+            assert field
             field.fieldtype.write(io_out, val, otherfields)
 
-    def read(self, io_in: BufferedIOBase, otherfields: Dict[str, Any]) -> Dict[str, Any]:
+    def read(self, io_in: BufferedIOBase, otherfields: Dict[str, Any]) -> Optional[Dict[str, Any]]:
         vals = {}
         for field in self.fields:
             val = field.fieldtype.read(io_in, otherfields)
@@ -383,25 +395,46 @@ class MessageType(SubtypeType):
         messagetype.add_field(field)
 
 
-class TlvStreamType(SubtypeType):
-    """A TlvStreamType is just a Subtype, but its fields are
-TlvMessageTypes.  In the CSV format these are created implicitly, when
-a tlvtype line (which defines a TlvMessageType within the TlvType,
-confusingly) refers to them.
+class TlvMessageType(MessageType):
+    """A 'tlvtype' in BOLT-speak"""
+
+    def __init__(self, name: str, value: str):
+        super().__init__(name, value)
+
+    def __str__(self):
+        return "tlvmsgtype-{}".format(self.name)
+
+
+class TlvStreamType(FieldType):
+    """A TlvStreamType's fields are TlvMessageTypes.  In the CSV format
+these are created implicitly, when a tlvtype line (which defines a
+TlvMessageType within the TlvType, confusingly) refers to them.
 
     """
     def __init__(self, name):
         super().__init__(name)
+        self.fields: List[TlvMessageType] = []
 
     def __str__(self):
         return "tlvstreamtype-{}".format(self.name)
 
-    def find_field_by_number(self, num: int) -> Optional['TlvMessageType']:
+    def find_field(self, fieldname: str) -> Optional[TlvMessageType]:
+        for f in self.fields:
+            if f.name == fieldname:
+                return f
+        return None
+
+    def find_field_by_number(self, num: int) -> Optional[TlvMessageType]:
         for f in self.fields:
             if f.number == num:
                 return f
         return None
 
+    def add_field(self, field: TlvMessageType) -> None:
+        if self.find_field(field.name):
+            raise ValueError("{}: duplicate field {}".format(self, field))
+        self.fields.append(field)
+
     def is_optional(self) -> bool:
         """You can omit a tlvstream= altogether"""
         return True
@@ -438,7 +471,7 @@ tlvdata,reply_channel_range_tlvs,timestamps_tlv,encoding_type,u8,
             raise ValueError("Unknown tlv field {}.{}"
                              .format(tlvstream, parts[1]))
 
-        subfield = field._field_from_csv(namespace, parts[2:], ellipsisok=True)
+        subfield = field._field_from_csv(namespace, parts[2:])
         field.add_field(subfield)
 
     def val_from_str(self, s: str) -> Tuple[Dict[str, Any], str]:
@@ -480,7 +513,9 @@ tlvdata,reply_channel_range_tlvs,timestamps_tlv,encoding_type,u8,
     def val_to_py(self, val: Dict[str, Any], otherfields: Dict[str, Any]) -> Dict[str, Any]:
         ret: Dict[str, Any] = {}
         for k, v in val.items():
-            ret[k] = self.find_field(k).val_to_py(v, val)
+            field = self.find_field(k)
+            assert field
+            ret[k] = field.val_to_py(v, val)
         return ret
 
     def write(self, io_out: BufferedIOBase, v: Optional[Dict[str, Any]], otherfields: Dict[str, Any]) -> None:
@@ -490,14 +525,16 @@ tlvdata,reply_channel_range_tlvs,timestamps_tlv,encoding_type,u8,
 
         # Make a tuple of (fieldnum, val_to_bin, val) so we can sort into
         # ascending order as TLV spec requires.
-        def write_raw_val(iobuf, val, otherfields: Dict[str, Any]):
+        def write_raw_val(iobuf: BufferedIOBase, val: Any, otherfields: Dict[str, Any]) -> None:
             iobuf.write(val)
 
         def get_value(tup):
             """Get value from num, fun, val tuple"""
             return tup[0]
 
-        ordered = []
+        ordered: List[Tuple[int,
+                            Callable[[BufferedIOBase, Any, Dict[str, Any]], None],
+                            Any]] = []
         for fieldname in v:
             f = self.find_field(fieldname)
             if f is None:
@@ -510,13 +547,13 @@ tlvdata,reply_channel_range_tlvs,timestamps_tlv,encoding_type,u8,
 
         for typenum, writefunc, val in ordered:
             buf = BytesIO()
-            writefunc(buf, val, otherfields)
+            writefunc(cast(BufferedIOBase, buf), val, otherfields)
             BigSizeType.write(io_out, typenum)
             BigSizeType.write(io_out, len(buf.getvalue()))
             io_out.write(buf.getvalue())
 
-    def read(self, io_in: BufferedIOBase, otherfields: Dict[str, Any]) -> Dict[str, Any]:
-        vals: Dict[str, Any] = {}
+    def read(self, io_in: BufferedIOBase, otherfields: Dict[str, Any]) -> Dict[Union[str, int], Any]:
+        vals: Dict[Union[str, int], Any] = {}
 
         while True:
             tlv_type = BigSizeType.read(io_in)
@@ -543,16 +580,6 @@ tlvdata,reply_channel_range_tlvs,timestamps_tlv,encoding_type,u8,
         return " {}={}".format(name, self.val_to_str(v, {}))
 
 
-class TlvMessageType(MessageType):
-    """A 'tlvtype' in BOLT-speak"""
-
-    def __init__(self, name: str, value: str):
-        super().__init__(name, value)
-
-    def __str__(self):
-        return "tlvmsgtype-{}".format(self.name)
-
-
 class Message(object):
     """A particular message instance"""
     def __init__(self, messagetype: MessageType, **kwargs):
@@ -679,7 +706,8 @@ Must not have missing fields.
         """Convert to a Python native object: dicts, lists, strings, ints"""
         ret: Dict[str, Union[Dict[str, Any], List[Any], str, int]] = {}
         for f, v in self.fields.items():
-            fieldtype = self.messagetype.find_field(f).fieldtype
-            ret[f] = fieldtype.val_to_py(v, self.fields)
+            field = self.messagetype.find_field(f)
+            assert field
+            ret[f] = field.fieldtype.val_to_py(v, self.fields)
 
         return ret