add

ccxt/static_dependencies/ethereum/utils/abi.py

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+from typing import (
+    Any,
+    Dict,
+)
+
+from .conversions import (
+    to_bytes
+)
+
+from ...keccak import (
+    SHA3 as keccak,
+)
+
+
+def collapse_if_tuple(abi: Dict[str, Any]) -> str:
+    """
+    Converts a tuple from a dict to a parenthesized list of its types.
+
+    >>> from eth_utils.abi import collapse_if_tuple
+    >>> collapse_if_tuple(
+    ...     {
+    ...         'components': [
+    ...             {'name': 'anAddress', 'type': 'address'},
+    ...             {'name': 'anInt', 'type': 'uint256'},
+    ...             {'name': 'someBytes', 'type': 'bytes'},
+    ...         ],
+    ...         'type': 'tuple',
+    ...     }
+    ... )
+    '(address,uint256,bytes)'
+    """
+    typ = abi["type"]
+    if not isinstance(typ, str):
+        raise TypeError(
+            f"The 'type' must be a string, but got {repr(typ)} of type {type(typ)}"
+        )
+    elif not typ.startswith("tuple"):
+        return typ
+
+    delimited = ",".join(collapse_if_tuple(c) for c in abi["components"])
+    # Whatever comes after "tuple" is the array dims. The ABI spec states that
+    # this will have the form "", "[]", or "[k]".
+    array_dim = typ[5:]
+    collapsed = f"({delimited}){array_dim}"
+
+    return collapsed
+
+
+def _abi_to_signature(abi: Dict[str, Any]) -> str:
+    fn_input_types = ",".join(
+        [collapse_if_tuple(abi_input) for abi_input in abi.get("inputs", [])]
+    )
+    function_signature = f"{abi['name']}({fn_input_types})"
+    return function_signature
+
+
+def function_signature_to_4byte_selector(event_signature: str) -> bytes:
+    return keccak(to_bytes(text=event_signature.replace(" ", "")))[:4]
+
+
+def function_abi_to_4byte_selector(function_abi: Dict[str, Any]) -> bytes:
+    function_signature = _abi_to_signature(function_abi)
+    return function_signature_to_4byte_selector(function_signature)
+
+
+def event_signature_to_log_topic(event_signature: str) -> bytes:
+    return keccak(to_bytes(text=event_signature.replace(" ", "")))
+
+
+def event_abi_to_log_topic(event_abi: Dict[str, Any]) -> bytes:
+    event_signature = _abi_to_signature(event_abi)
+    return event_signature_to_log_topic(event_signature)