Initialize contracts having function or event overrides #3476

reedsa · 2024-09-04T22:33:52Z

What was wrong?

The Contract class cannot initialize if the contract contains overloaded functions or events. Currently only the function/event name is used to filter ABI events from the contract ABI, so an exception is raised. Currently, events raise a ValueError when _get_event_abi is called on the Contract or ContractEvent class. Functions raise a MismatchedABI error.

Example:
BaseContractEvent._get_event_abi() calls eth-utils get_event_abi() and expects to return the ABI for the event class. The event classes are not created for every overloaded function. When there are contract events with the same name, only one is ever created and used.

How was it fixed?

Initialize the ContractFunctions or ContractEvents class with every ABI found in the contract, storing the abi signature in the class name. Along with the signature, the abi property is set for each class within the __init__ method. This ensures the correct instance is found and used for subsequent functions like get_logs().

get_abi_element now handles both functions and events using the ABI signature to find a unique ABI. The signature is represented by a string that includes it's name and list of input types within parentheses. name(arg1Type,arg2Type,...)

Exceptions are now shared between functions and events for consistency.

Todo:

Clean up commit history
Add or update documentation related to these changes
Add entry to the release notes

Cute Animal Picture

kclowes

LGTM! Just left a few nits!

kclowes · 2024-09-06T15:30:23Z

tests/core/contracts/conftest.py

@@ -760,3 +785,4 @@ def async_call(request):
 @pytest.fixture
 def async_estimate_gas(request):
    return async_partial(async_invoke_contract, api_call_desig="estimate_gas")
+    return async_partial(async_invoke_contract, api_call_desig="estimate_gas")


copy pasta?

kclowes · 2024-09-06T15:35:05Z

tests/core/contracts/test_contract_ambiguous_events.py

+    assert event_abi == ABI_EVENT_DEPOSIT
+
+
+def test_get_abi_element_with_signature_for_amibguous_tuple_events() -> None:


nit:

Suggested change

def test_get_abi_element_with_signature_for_amibguous_tuple_events() -> None:

def test_get_abi_element_with_signature_for_amibiguous_tuple_events() -> None:

tests/core/utilities/test_abi.py

kclowes · 2024-09-06T15:58:08Z

web3/contract/base_contract.py

+    def __init__(
+        self,
+        *argument_names: Tuple[str],
+        abi: ABIEvent = None,


nit?

Suggested change

abi: ABIEvent = None,

abi: Optional[ABIEvent] = None,

kclowes · 2024-09-06T16:07:49Z

web3/contract/base_contract.py


    def __getattr__(self, event_name: str) -> Type["BaseContractEvent"]:
        if "_events" not in self.__dict__:
            raise NoABIEventsFound(
                "The abi for this contract contains no event definitions. ",
                "Are you sure you provided the correct contract abi?",
            )
-        elif event_name not in self.__dict__["_events"]:
+        elif event_name.split("(")[0] not in [


this event_name.split... may deserve to be its own method since you're using it so much in here. Feel free to take or leave :)

kclowes · 2024-09-06T16:17:46Z

newsfragments/3476.feature.rst

@@ -0,0 +1 @@
+Contracts which overloaded functions or events are now supported. The Contract initializes functions and events using an identifier to distinguish between them. The identifier is the function or event signature, which consists of the name and the parameter types.


nit:

Suggested change

Contracts which overloaded functions or events are now supported. The Contract initializes functions and events using an identifier to distinguish between them. The identifier is the function or event signature, which consists of the name and the parameter types.

Contracts with overloaded functions or events are now supported. The Contract initializes functions and events using an identifier to distinguish between them. The identifier is the function or event signature, which consists of the name and the parameter types.

kclowes · 2024-09-06T16:23:39Z

web3/contract/base_contract.py

-                    *self.args,
-                    abi_codec=self.w3.codec,
-                    **self.kwargs,
+                    cls.contract_abi, get_abi_element_identifier(abi_element_identifier)


Does this need the codec passed too?

reedsa · 2024-09-06T20:12:32Z

The ambiguity with functions is also an issue unfortunately. Taking a look at how to disambiguate since right now it uses the "first" one.

pacrob · 2024-09-12T17:02:10Z

tests/ens/test_offchain_resolution.py

@@ -173,14 +173,14 @@ def test_offchain_resolver_function_call_raises_with_ccip_read_disabled(
    with pytest.raises(OffchainLookup):
        offchain_resolver.functions.resolve(
            ens_encode_name("offchainexample.eth"),
-            ENCODED_ADDR_CALLDATA,
+            ENCODED_ADDR_CALLDATA.encode(),


Why the added encode here? Test passes for me with or without it.

No need for this after all, good callout.

pacrob · 2024-09-12T18:18:37Z

web3/contract/contract.py

+
+    def __iter__(self) -> Iterable["ContractEvent"]:
+        """
+        Iterate over supported


nit - docstring should state what the function does (not sure if it's necessary for a magic method?). Also should match for the same method in AsyncContractEvents.

Good point, there's no practical information I provided there anyway. Removing!

pacrob · 2024-09-12T18:30:36Z

web3/utils/abi.py

 ) -> ABIElement:
    """
-    Return the interface for an ``ABIElement`` which matches the provided identifier
-    and arguments.
+    Return the interface for an ``ABIElement`` from the `abi` that matches the provided


Suggested change

Return the interface for an ``ABIElement`` from the `abi` that matches the provided

Return the interface for an ``ABIElement`` from the ``abi`` that matches the provided

pacrob · 2024-09-12T18:31:26Z

web3/utils/abi.py

 def get_event_abi(
    abi: ABI,
    event_name: str,
    argument_names: Optional[Sequence[str]] = None,
 ) -> ABIEvent:
    """
+    .. warning::
+        This function is deprecated. It is unable to distinguish between
+        overloaded events. Use `get_abi_element` instead.


Suggested change

overloaded events. Use `get_abi_element` instead.

overloaded events. Use ``get_abi_element`` instead.

__getattr__ now uses the ABI to look up the function class by signature Additional fixes for ens

Refactoring and docs update for ``get_abi_element`` and ``_build_filters`` Rename ``get_abi_element_identifier`` -> ``get_abi_element_signature``

…ith_name`` Further cleanup and refactoring

Fix contract compilation and naming

Remove docs from events iter Fix docstring formatting

pacrob · 2024-09-13T16:00:44Z

web3/utils/abi.py

+    filter is a partial function that takes a contract ABI and returns a filtered list.
+    Each parameter is checked before applying the relevant filter.
+
+    When the `abi_element_identifier` is a function name or signature and no arguments


Suggested change

When the `abi_element_identifier` is a function name or signature and no arguments

When the ``abi_element_identifier`` is a function name or signature and no arguments

pacrob · 2024-09-13T16:01:10Z

web3/utils/abi.py

+    filters include the function name, argument count, argument name, argument type,
+    and argument encodability.
+
+    `constructor`, `fallback`, and `receive` ABI elements are handled only with a


Suggested change

`constructor`, `fallback`, and `receive` ABI elements are handled only with a

``constructor``, ``fallback``, and ``receive`` ABI elements are handled only with a

pacrob · 2024-09-13T16:15:41Z

web3/utils/abi.py

-    :param abi_element_identifier: Find an element ABI with matching identifier.
+    :param abi_element_identifier: Find an element ABI with matching identifier. The \
+    identifier may be a function name, signature, or ``FallbackFn`` or ``ReceiveFn``. \
+    A function signature is in the form `name(arg1Type,arg2Type,...)`.


Suggested change

A function signature is in the form `name(arg1Type,arg2Type,...)`.

A function signature is in the form ``name(arg1Type,arg2Type,...)``.

pacrob

🐑

kclowes

Sweet! I didn't see anything major, just left a few small comments.

kclowes · 2024-09-13T17:30:42Z