Merge pull request #9 from curvefi/feat/polygon-zkevm

Polygon zkEVM bridger

contracts/bridgers/PolygonzkEVMBridger.vy

@@ -0,0 +1,59 @@
+# @version 0.3.10
+"""
+@title Curve Polygon zkEVM Bridge Wrapper
+"""
+from vyper.interfaces import ERC20
+
+
+interface PolygonZkEVMBridge:
+    def bridgeAsset(destination_network: uint32, destination_address: address, amount: uint256, token: address, force_update: bool, permit_data: Bytes[2]): nonpayable
+
+
+CRV20: constant(address) = 0xD533a949740bb3306d119CC777fa900bA034cd52
+L1_BRIDGE: immutable(PolygonZkEVMBridge)
+
+DESTINATION_NETWORK: immutable(uint32)
+
+
+@external
+def __init__(_l1_bridge: PolygonZkEVMBridge, _network: uint32):
+    L1_BRIDGE = _l1_bridge
+    assert ERC20(CRV20).approve(_l1_bridge.address, max_value(uint256))
+
+    DESTINATION_NETWORK = _network
+
+
+@external
+def bridge(_token: ERC20, _to: address, _amount: uint256):
+    """
+    @notice Bridge a token to Polygon zkEVM using built-in PolygonZkEVMBridge
+    @dev Might need `claimAsset` on destination chain, save `depositCount` from POLYGON_ZKEVM_BRIDGE.BridgeEvent
+    @param _token The token to bridge
+    @param _to The address to deposit the token to on L2
+    @param _amount The amount of the token to deposit
+    """
+    assert _token.transferFrom(msg.sender, self, _amount)
+
+    if _token.allowance(self, L1_BRIDGE.address) < _amount:
+        _token.approve(L1_BRIDGE.address, max_value(uint256))
+
+    L1_BRIDGE.bridgeAsset(DESTINATION_NETWORK, _to, _amount, _token.address, True, b"")
+
+
+@view
+@external
+def check(_account: address) -> bool:
+    """
+    @notice Dummy method to check if caller is allowed to bridge
+    @param _account The account to check
+    """
+    return True
+
+
+@view
+@external
+def cost() -> uint256:
+    """
+    @notice Cost in ETH to bridge
+    """
+    return 0

tests/forked/test_bridgers.py

@@ -142,3 +142,20 @@ def test_harmony_bridger(alice, crv_token, HarmonyBridger):
     assert crv_token.balanceOf(harmony_bridge) == balance_before + 10**18
     assert "Locked" in tx.events
     assert tx.events["Locked"].values() == [crv_token, bridger, 10**18, alice]
+
+
+def test_polygonzkevm_bridger(alice, crv_token, PolygonzkEVMBridger):
+    bridge = "0x2a3DD3EB832aF982ec71669E178424b10Dca2EDe"
+    bridger = PolygonzkEVMBridger.deploy(bridge, 3, {"from": alice})
+
+    assert bridger.cost() == 0
+    assert bridger.check(alice) is True
+
+    crv_token.approve(bridger, 2**256 - 1, {"from": alice})
+
+    balance_before = crv_token.balanceOf(bridge)
+    tx = bridger.bridge(crv_token, alice, 10**18, {"from": alice})
+
+    assert crv_token.balanceOf(bridge) == balance_before + 10**18
+    assert "BridgeEvent" in tx.events
+    assert tx.events["BridgeEvent"].values()[2:5] == [crv_token, 3, bridger]