Add type hints and clean up ABI code (#253)

* Add type hints and clean up ABI types

* Change relative imports to absolute imports

* Add type hints for ABI objects

* Refactor composer with type hints

* Address PR comments, change list type hints, and move type_from_string to ABIType

Author: algochoi

algosdk/abi/__init__.py

@@ -1,14 +1,13 @@
-from .util import type_from_string
-from .uint_type import UintType
-from .ufixed_type import UfixedType
-from .base_type import ABIType
-from .bool_type import BoolType
-from .byte_type import ByteType
-from .address_type import AddressType
-from .string_type import StringType
-from .array_dynamic_type import ArrayDynamicType
-from .array_static_type import ArrayStaticType
-from .tuple_type import TupleType
+from algosdk.abi.uint_type import UintType
+from algosdk.abi.ufixed_type import UfixedType
+from algosdk.abi.base_type import ABIType
+from algosdk.abi.bool_type import BoolType
+from algosdk.abi.byte_type import ByteType
+from algosdk.abi.address_type import AddressType
+from algosdk.abi.string_type import StringType
+from algosdk.abi.array_dynamic_type import ArrayDynamicType
+from algosdk.abi.array_static_type import ArrayStaticType
+from algosdk.abi.tuple_type import TupleType
 from .method import Method, Argument, Returns
 from .interface import Interface
 from .contract import Contract

algosdk/abi/address_type.py

@@ -1,7 +1,9 @@
-from .base_type import ABIType
-from .byte_type import ByteType
-from .tuple_type import TupleType
-from .. import error
+from typing import Union
+
+from algosdk.abi.base_type import ABIType
+from algosdk.abi.byte_type import ByteType
+from algosdk.abi.tuple_type import TupleType
+from algosdk import error
 
 from algosdk import encoding
 
@@ -14,18 +16,18 @@ class AddressType(ABIType):
     def __init__(self) -> None:
         super().__init__()
 
-    def __eq__(self, other) -> bool:
+    def __eq__(self, other: object) -> bool:
         if not isinstance(other, AddressType):
             return False
         return True
 
-    def __str__(self):
+    def __str__(self) -> str:
         return "address"
 
-    def byte_len(self):
+    def byte_len(self) -> int:
         return 32
 
-    def is_dynamic(self):
+    def is_dynamic(self) -> bool:
         return False
 
     def _to_tuple_type(self):
@@ -34,7 +36,7 @@ def _to_tuple_type(self):
             child_type_array.append(ByteType())
         return TupleType(child_type_array)
 
-    def encode(self, value):
+    def encode(self, value: Union[str, bytes]) -> bytes:
         """
         Encode an address string or a 32-byte public key into a Address ABI bytestring.
 
@@ -62,7 +64,7 @@ def encode(self, value):
             )
         return bytes(value)
 
-    def decode(self, bytestring):
+    def decode(self, bytestring: Union[bytearray, bytes]) -> str:
         """
         Decodes a bytestring to a base32 encoded address string.
 

algosdk/abi/array_dynamic_type.py

@@ -1,45 +1,47 @@
-from .base_type import ABI_LENGTH_SIZE, ABIType
-from .byte_type import ByteType
-from .tuple_type import TupleType
-from .. import error
+from typing import Any, List, NoReturn, Union
+
+from algosdk.abi.base_type import ABI_LENGTH_SIZE, ABIType
+from algosdk.abi.byte_type import ByteType
+from algosdk.abi.tuple_type import TupleType
+from algosdk import error
 
 
 class ArrayDynamicType(ABIType):
     """
     Represents a ArrayDynamic ABI Type for encoding.
 
     Args:
-        child_type (Type): the type of the dynamic array.
+        child_type (ABIType): the type of the dynamic array.
 
     Attributes:
-        child_type (Type)
+        child_type (ABIType)
     """
 
-    def __init__(self, arg_type) -> None:
+    def __init__(self, arg_type: ABIType) -> None:
         super().__init__()
         self.child_type = arg_type
 
-    def __eq__(self, other) -> bool:
+    def __eq__(self, other: object) -> bool:
         if not isinstance(other, ArrayDynamicType):
             return False
         return self.child_type == other.child_type
 
-    def __str__(self):
+    def __str__(self) -> str:
         return "{}[]".format(self.child_type)
 
-    def byte_len(self):
+    def byte_len(self) -> NoReturn:
         raise error.ABITypeError(
             "cannot get length of a dynamic type: {}".format(self)
         )
 
-    def is_dynamic(self):
+    def is_dynamic(self) -> bool:
         return True
 
-    def _to_tuple_type(self, length):
+    def _to_tuple_type(self, length: int) -> TupleType:
         child_type_array = [self.child_type] * length
         return TupleType(child_type_array)
 
-    def encode(self, value_array):
+    def encode(self, value_array: Union[List[Any], bytes, bytearray]) -> bytes:
         """
         Encodes a list of values into a ArrayDynamic ABI bytestring.
 
@@ -67,7 +69,7 @@ def encode(self, value_array):
         encoded = converted_tuple.encode(value_array)
         return bytes(length_to_encode) + encoded
 
-    def decode(self, array_bytes):
+    def decode(self, array_bytes: Union[bytes, bytearray]) -> list:
         """
         Decodes a bytestring to a dynamic list.
 

algosdk/abi/array_static_type.py

@@ -1,62 +1,63 @@
 import math
+from typing import Any, List, Union
 
-from .base_type import ABIType
-from .bool_type import BoolType
-from .byte_type import ByteType
-from .tuple_type import TupleType
-from .. import error
+from algosdk.abi.base_type import ABIType
+from algosdk.abi.bool_type import BoolType
+from algosdk.abi.byte_type import ByteType
+from algosdk.abi.tuple_type import TupleType
+from algosdk import error
 
 
 class ArrayStaticType(ABIType):
     """
     Represents a ArrayStatic ABI Type for encoding.
 
     Args:
-        child_type (Type): the type of the child_types array.
-        static_length (int): length of the static array.
+        child_type (ABIType): the type of the child_types array.
+        array_len (int): length of the static array.
 
     Attributes:
-        child_type (Type)
+        child_type (ABIType)
         static_length (int)
     """
 
-    def __init__(self, arg_type, array_len) -> None:
+    def __init__(self, arg_type: ABIType, array_len: int) -> None:
         if array_len < 1:
             raise error.ABITypeError(
                 "static array length must be a positive integer: {}".format(
-                    len(array_len)
+                    array_len
                 )
             )
         super().__init__()
         self.child_type = arg_type
         self.static_length = array_len
 
-    def __eq__(self, other) -> bool:
+    def __eq__(self, other: object) -> bool:
         if not isinstance(other, ArrayStaticType):
             return False
         return (
             self.child_type == other.child_type
             and self.static_length == other.static_length
         )
 
-    def __str__(self):
+    def __str__(self) -> str:
         return "{}[{}]".format(self.child_type, self.static_length)
 
-    def byte_len(self):
+    def byte_len(self) -> int:
         if isinstance(self.child_type, BoolType):
             # 8 Boolean values can be encoded into 1 byte
             return math.ceil(self.static_length / 8)
         element_byte_length = self.child_type.byte_len()
         return self.static_length * element_byte_length
 
-    def is_dynamic(self):
+    def is_dynamic(self) -> bool:
         return self.child_type.is_dynamic()
 
-    def _to_tuple_type(self):
+    def _to_tuple_type(self) -> TupleType:
         child_type_array = [self.child_type] * self.static_length
         return TupleType(child_type_array)
 
-    def encode(self, value_array):
+    def encode(self, value_array: Union[List[Any], bytes, bytearray]) -> bytes:
         """
         Encodes a list of values into a ArrayStatic ABI bytestring.
 
@@ -87,7 +88,7 @@ def encode(self, value_array):
         converted_tuple = self._to_tuple_type()
         return converted_tuple.encode(value_array)
 
-    def decode(self, array_bytes):
+    def decode(self, array_bytes: Union[bytes, bytearray]) -> list:
         """
         Decodes a bytestring to a static list.
 

algosdk/abi/base_type.py

@@ -1,51 +1,139 @@
 from abc import ABC, abstractmethod
+import re
+from typing import Any, Union
+
+from algosdk import error
+
 
 # Globals
 ABI_LENGTH_SIZE = 2  # We use 2 bytes to encode the length of a dynamic element
+UFIXED_REGEX = r"^ufixed([1-9][\d]*)x([1-9][\d]*)$"
+STATIC_ARRAY_REGEX = r"^([a-z\d\[\](),]+)\[([1-9][\d]*)]$"
 
 
 class ABIType(ABC):
     """
     Represents an ABI Type for encoding.
     """
 
-    def __init__(
-        self,
-    ) -> None:
+    def __init__(self) -> None:
         pass
 
     @abstractmethod
-    def __str__(self):
+    def __str__(self) -> str:
         pass
 
     @abstractmethod
-    def __eq__(self, other) -> bool:
+    def __eq__(self, other: object) -> bool:
         pass
 
     @abstractmethod
-    def is_dynamic(self):
+    def is_dynamic(self) -> bool:
         """
         Return whether the ABI type is dynamic.
         """
         pass
 
     @abstractmethod
-    def byte_len(self):
+    def byte_len(self) -> int:
         """
         Return the length in bytes of the ABI type.
         """
         pass
 
     @abstractmethod
-    def encode(self, value):
+    def encode(self, value: Any) -> bytes:
         """
         Serialize the ABI value into a byte string using ABI encoding rules.
         """
         pass
 
     @abstractmethod
-    def decode(self, bytestring):
+    def decode(self, bytestring: bytes) -> Any:
         """
         Deserialize the ABI type and value from a byte string using ABI encoding rules.
         """
         pass
+
+    @staticmethod
+    def from_string(s: str) -> "ABIType":
+        """
+        Convert a valid ABI string to a corresponding ABI type.
+        """
+        # We define the imports here to avoid circular imports
+        from algosdk.abi.uint_type import UintType
+        from algosdk.abi.ufixed_type import UfixedType
+        from algosdk.abi.byte_type import ByteType
+        from algosdk.abi.bool_type import BoolType
+        from algosdk.abi.address_type import AddressType
+        from algosdk.abi.string_type import StringType
+        from algosdk.abi.array_dynamic_type import ArrayDynamicType
+        from algosdk.abi.array_static_type import ArrayStaticType
+        from algosdk.abi.tuple_type import TupleType
+
+        if s.endswith("[]"):
+            array_arg_type = ABIType.from_string(s[:-2])
+            return ArrayDynamicType(array_arg_type)
+        elif s.endswith("]"):
+            matches = re.search(STATIC_ARRAY_REGEX, s)
+            try:
+                static_length = int(matches.group(2))
+                array_type = ABIType.from_string(matches.group(1))
+                return ArrayStaticType(array_type, static_length)
+            except Exception as e:
+                raise error.ABITypeError(
+                    "malformed static array string: {}".format(s)
+                ) from e
+        if s.startswith("uint"):
+            try:
+                if not s[4:].isdecimal():
+                    raise error.ABITypeError(
+                        "uint string does not contain a valid size: {}".format(
+                            s
+                        )
+                    )
+                type_size = int(s[4:])
+                return UintType(type_size)
+            except Exception as e:
+                raise error.ABITypeError(
+                    "malformed uint string: {}".format(s)
+                ) from e
+        elif s == "byte":
+            return ByteType()
+        elif s.startswith("ufixed"):
+            matches = re.search(UFIXED_REGEX, s)
+            try:
+                bit_size = int(matches.group(1))
+                precision = int(matches.group(2))
+                return UfixedType(bit_size, precision)
+            except Exception as e:
+                raise error.ABITypeError(
+                    "malformed ufixed string: {}".format(s)
+                ) from e
+        elif s == "bool":
+            return BoolType()
+        elif s == "address":
+            return AddressType()
+        elif s == "string":
+            return StringType()
+        elif len(s) >= 2 and s[0] == "(" and s[-1] == ")":
+            # Recursively parse parentheses from a tuple string
+            tuples = TupleType._parse_tuple(s[1:-1])
+            tuple_list = []
+            for tup in tuples:
+                if isinstance(tup, str):
+                    tt = ABIType.from_string(tup)
+                    tuple_list.append(tt)
+                elif isinstance(tup, list):
+                    tts = [ABIType.from_string(t_) for t_ in tup]
+                    tuple_list.append(tts)
+                else:
+                    raise error.ABITypeError(
+                        "cannot convert {} to an ABI type".format(tup)
+                    )
+
+            return TupleType(tuple_list)
+        else:
+            raise error.ABITypeError(
+                "cannot convert {} to an ABI type".format(s)
+            )