Feat etherscan api

brownie/network/contract.py

@@ -581,7 +581,8 @@ def from_explorer(
         as_proxy_for : str, optional
             Address of the implementation contract, if `address` is a proxy contract.
             The generated object will send transactions to `address`, but use the ABI
-            and NatSpec of `as_proxy_for`.
+            and NatSpec of `as_proxy_for`. This field is only required when the
+            block explorer API does not provide an implementation address.
         owner : Account, optional
             Contract owner. If set, transactions without a `from` field will be
             performed using this account.
@@ -596,18 +597,21 @@ def from_explorer(
         else:
             # if the source is not available, try to fetch only the ABI
             try:
-                data = _fetch_from_explorer(address, "getabi", True)
+                data_abi = _fetch_from_explorer(address, "getabi", True)
             except ValueError as exc:
                 _unverified_addresses.add(address)
                 raise exc
-            abi = json.loads(data["result"].strip())
+            abi = json.loads(data_abi["result"].strip())
             name = "UnknownContractName"
             warnings.warn(
                 f"{address}: Was able to fetch the ABI but not the source code. "
                 "Some functionality will not be available.",
                 BrownieCompilerWarning,
             )
 
+        if as_proxy_for is None and data["result"][0].get("Implementation"):
+            as_proxy_for = _resolve_address(data["result"][0]["Implementation"])
+
         # if this is a proxy, fetch information for the implementation contract
         if as_proxy_for is not None:
             implementation_contract = Contract.from_explorer(as_proxy_for)
@@ -639,7 +643,14 @@ def from_explorer(
             "enabled": bool(int(data["result"][0]["OptimizationUsed"])),
             "runs": int(data["result"][0]["Runs"]),
         }
-        build = compile_and_format(sources, solc_version=str(version), optimizer=optimizer)
+
+        evm_version = data["result"][0].get("EVMVersion", "Default")
+        if evm_version == "Default":
+            evm_version = None
+
+        build = compile_and_format(
+            sources, solc_version=str(version), optimizer=optimizer, evm_version=evm_version
+        )
         build = build[name]
         if as_proxy_for is not None:
             build.update(abi=abi, natspec=implementation_contract._build.get("natspec"))

brownie/project/compiler/__init__.py

@@ -4,7 +4,7 @@
 from copy import deepcopy
 from hashlib import sha1
 from pathlib import Path
-from typing import Dict, Optional, Union
+from typing import Dict, Optional
 
 from eth_utils import remove_0x_prefix
 from semantic_version import Version
@@ -49,7 +49,7 @@ def compile_and_format(
     solc_version: Optional[str] = None,
     optimize: bool = True,
     runs: int = 200,
-    evm_version: int = None,
+    evm_version: Optional[str] = None,
     silent: bool = True,
     allow_paths: Optional[str] = None,
     interface_sources: Optional[Dict[str, str]] = None,
@@ -143,7 +143,7 @@ def generate_input_json(
     contract_sources: Dict[str, str],
     optimize: bool = True,
     runs: int = 200,
-    evm_version: Union[int, str, None] = None,
+    evm_version: Optional[str] = None,
     language: str = "Solidity",
     interface_sources: Optional[Dict[str, str]] = None,
     remappings: Optional[list] = None,

docs/api-network.rst

@@ -819,7 +819,7 @@ New ``Contract`` objects are created with one of the following class methods.
     Create a new ``Contract`` object from source code fetched from a block explorer such as `EtherScan <https://etherscan.io/>`_ or `Blockscout <https://blockscout.com/>`_.
 
     * ``address``: Address of the contract.
-    * ``as_proxy_for``: Address of the implementation contract, if ``address`` is a proxy contract. The generated object sends transactions to ``address``, but uses the ABI and NatSpec of ``as_proxy_for``.
+    * ``as_proxy_for``: Address of the implementation contract, if ``address`` is a proxy contract. The generated object sends transactions to ``address``, but uses the ABI and NatSpec of ``as_proxy_for``. This field is only required when the block explorer API does not provide an implementation address.
     * ``owner``: An optional :func:`Account <brownie.network.account.Account>` instance. If given, transactions to the contract are sent broadcasted from this account by default.
 
     If the deployed bytecode was generated using a compatible compiler version, Brownie will attempt to recompile it locally. If successful, most debugging functionality will be available.

tests/network/contract/test_contract.py

@@ -303,7 +303,8 @@ def test_as_proxy_for(network):
         as_proxy_for="0x97BD4Cc841FC999194174cd1803C543247a014fe",
     )
     implementation = Contract("0x97BD4Cc841FC999194174cd1803C543247a014fe")
-    assert original.abi != proxy.abi
+
+    assert original.abi == proxy.abi
     assert original.address == proxy.address
 
     assert proxy.abi == implementation.abi