Added cream bridge contract

contracts/asset-proxy/contracts/src/bridges/CreamBridge.sol

@@ -0,0 +1,103 @@
+
+/*
+
+  Copyright 2020 ZeroEx Intl.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+*/
+
+pragma solidity ^0.5.9;
+pragma experimental ABIEncoderV2;
+
+import "@0x/contracts-erc20/contracts/src/interfaces/IERC20Token.sol";
+import "@0x/contracts-erc20/contracts/src/LibERC20Token.sol";
+import "@0x/contracts-exchange-libs/contracts/src/IWallet.sol";
+import "@0x/contracts-utils/contracts/src/DeploymentConstants.sol";
+import "../interfaces/IERC20Bridge.sol";
+import "../interfaces/IBalancerPool.sol";
+
+
+contract CreamBridge is
+    IERC20Bridge,
+    IWallet,
+    DeploymentConstants
+{
+    /// @dev Callback for `IERC20Bridge`. Tries to buy `amount` of
+    ///      `toTokenAddress` tokens by selling the entirety of the `fromTokenAddress`
+    ///      token encoded in the bridge data, then transfers the bought
+    ///      tokens to `to`.
+    /// @param toTokenAddress The token to buy and transfer to `to`.
+    /// @param from The maker (this contract).
+    /// @param to The recipient of the bought tokens.
+    /// @param amount Minimum amount of `toTokenAddress` tokens to buy.
+    /// @param bridgeData The abi-encoded addresses of the "from" token and Balancer pool.
+    /// @return success The magic bytes if successful.
+    function bridgeTransferFrom(
+        address toTokenAddress,
+        address from,
+        address to,
+        uint256 amount,
+        bytes calldata bridgeData
+    )
+        external
+        returns (bytes4 success)
+    {
+        // Decode the bridge data.
+        (address fromTokenAddress, address poolAddress) = abi.decode(
+            bridgeData,
+            (address, address)
+        );
+        require(toTokenAddress != fromTokenAddress, "CreamBridge/INVALID_PAIR");
+
+        uint256 fromTokenBalance = IERC20Token(fromTokenAddress).balanceOf(address(this));
+        // Grant an allowance to the exchange to spend `fromTokenAddress` token.
+        LibERC20Token.approveIfBelow(fromTokenAddress, poolAddress, fromTokenBalance);
+
+        // Sell all of this contract's `fromTokenAddress` token balance.
+        (uint256 boughtAmount,) = IBalancerPool(poolAddress).swapExactAmountIn(
+            fromTokenAddress, // tokenIn
+            fromTokenBalance, // tokenAmountIn
+            toTokenAddress,   // tokenOut
+            amount,           // minAmountOut
+            uint256(-1)       // maxPrice
+        );
+
+        // Transfer the converted `toToken`s to `to`.
+        LibERC20Token.transfer(toTokenAddress, to, boughtAmount);
+
+        emit ERC20BridgeTransfer(
+            fromTokenAddress,
+            toTokenAddress,
+            fromTokenBalance,
+            boughtAmount,
+            from,
+            to
+        );
+        return BRIDGE_SUCCESS;
+    }
+
+    /// @dev `SignatureType.Wallet` callback, so that this bridge can be the maker
+    ///      and sign for itself in orders. Always succeeds.
+    /// @return magicValue Magic success bytes, always.
+    function isValidSignature(
+        bytes32,
+        bytes calldata
+    )
+        external
+        view
+        returns (bytes4 magicValue)
+    {
+        return LEGACY_WALLET_MAGIC_VALUE;
+    }
+}

contracts/asset-proxy/package.json

@@ -38,7 +38,7 @@
         "docs:json": "typedoc --excludePrivate --excludeExternals --excludeProtected --ignoreCompilerErrors --target ES5 --tsconfig typedoc-tsconfig.json --json $JSON_FILE_PATH $PROJECT_FILES"
     },
     "config": {
-        "abis": "./test/generated-artifacts/@(BalancerBridge|BancorBridge|ChaiBridge|CurveBridge|DexForwarderBridge|DydxBridge|ERC1155Proxy|ERC20BridgeProxy|ERC20Proxy|ERC721Proxy|Eth2DaiBridge|IAssetData|IAssetProxy|IAssetProxyDispatcher|IAuthorizable|IBalancerPool|IBancorNetwork|IChai|ICurve|IDydx|IDydxBridge|IERC20Bridge|IEth2Dai|IGasToken|IKyberNetworkProxy|IMStable|IMooniswap|IUniswapExchange|IUniswapExchangeFactory|IUniswapV2Router01|KyberBridge|MStableBridge|MixinAssetProxyDispatcher|MixinAuthorizable|MixinGasToken|MooniswapBridge|MultiAssetProxy|Ownable|StaticCallProxy|SushiSwapBridge|TestBancorBridge|TestChaiBridge|TestDexForwarderBridge|TestDydxBridge|TestERC20Bridge|TestEth2DaiBridge|TestKyberBridge|TestStaticCallTarget|TestUniswapBridge|TestUniswapV2Bridge|UniswapBridge|UniswapV2Bridge).json",
+        "abis": "./test/generated-artifacts/@(BalancerBridge|BancorBridge|ChaiBridge|CreamBridge|CurveBridge|DexForwarderBridge|DydxBridge|ERC1155Proxy|ERC20BridgeProxy|ERC20Proxy|ERC721Proxy|Eth2DaiBridge|IAssetData|IAssetProxy|IAssetProxyDispatcher|IAuthorizable|IBalancerPool|IBancorNetwork|IChai|ICurve|IDydx|IDydxBridge|IERC20Bridge|IEth2Dai|IGasToken|IKyberNetworkProxy|IMStable|IMooniswap|IUniswapExchange|IUniswapExchangeFactory|IUniswapV2Router01|KyberBridge|MStableBridge|MixinAssetProxyDispatcher|MixinAuthorizable|MixinGasToken|MooniswapBridge|MultiAssetProxy|Ownable|StaticCallProxy|SushiSwapBridge|TestBancorBridge|TestChaiBridge|TestDexForwarderBridge|TestDydxBridge|TestERC20Bridge|TestEth2DaiBridge|TestKyberBridge|TestStaticCallTarget|TestUniswapBridge|TestUniswapV2Bridge|UniswapBridge|UniswapV2Bridge).json",
         "abis:comment": "This list is auto-generated by contracts-gen. Don't edit manually."
     },
     "repository": {

contracts/asset-proxy/src/artifacts.ts

@@ -8,6 +8,7 @@ import { ContractArtifact } from 'ethereum-types';
 import * as BalancerBridge from '../generated-artifacts/BalancerBridge.json';
 import * as BancorBridge from '../generated-artifacts/BancorBridge.json';
 import * as ChaiBridge from '../generated-artifacts/ChaiBridge.json';
+import * as CreamBridge from '../generated-artifacts/CreamBridge.json';
 import * as CurveBridge from '../generated-artifacts/CurveBridge.json';
 import * as DexForwarderBridge from '../generated-artifacts/DexForwarderBridge.json';
 import * as DydxBridge from '../generated-artifacts/DydxBridge.json';
@@ -70,6 +71,7 @@ export const artifacts = {
     BalancerBridge: BalancerBridge as ContractArtifact,
     BancorBridge: BancorBridge as ContractArtifact,
     ChaiBridge: ChaiBridge as ContractArtifact,
+    CreamBridge: CreamBridge as ContractArtifact,
     CurveBridge: CurveBridge as ContractArtifact,
     DexForwarderBridge: DexForwarderBridge as ContractArtifact,
     DydxBridge: DydxBridge as ContractArtifact,

contracts/asset-proxy/src/wrappers.ts

@@ -6,6 +6,7 @@
 export * from '../generated-wrappers/balancer_bridge';
 export * from '../generated-wrappers/bancor_bridge';
 export * from '../generated-wrappers/chai_bridge';
+export * from '../generated-wrappers/cream_bridge';
 export * from '../generated-wrappers/curve_bridge';
 export * from '../generated-wrappers/dex_forwarder_bridge';
 export * from '../generated-wrappers/dydx_bridge';

contracts/asset-proxy/test/artifacts.ts

@@ -8,6 +8,7 @@ import { ContractArtifact } from 'ethereum-types';
 import * as BalancerBridge from '../test/generated-artifacts/BalancerBridge.json';
 import * as BancorBridge from '../test/generated-artifacts/BancorBridge.json';
 import * as ChaiBridge from '../test/generated-artifacts/ChaiBridge.json';
+import * as CreamBridge from '../test/generated-artifacts/CreamBridge.json';
 import * as CurveBridge from '../test/generated-artifacts/CurveBridge.json';
 import * as DexForwarderBridge from '../test/generated-artifacts/DexForwarderBridge.json';
 import * as DydxBridge from '../test/generated-artifacts/DydxBridge.json';
@@ -70,6 +71,7 @@ export const artifacts = {
     BalancerBridge: BalancerBridge as ContractArtifact,
     BancorBridge: BancorBridge as ContractArtifact,
     ChaiBridge: ChaiBridge as ContractArtifact,
+    CreamBridge: CreamBridge as ContractArtifact,
     CurveBridge: CurveBridge as ContractArtifact,
     DexForwarderBridge: DexForwarderBridge as ContractArtifact,
     DydxBridge: DydxBridge as ContractArtifact,

contracts/asset-proxy/test/wrappers.ts

@@ -6,6 +6,7 @@
 export * from '../test/generated-wrappers/balancer_bridge';
 export * from '../test/generated-wrappers/bancor_bridge';
 export * from '../test/generated-wrappers/chai_bridge';
+export * from '../test/generated-wrappers/cream_bridge';
 export * from '../test/generated-wrappers/curve_bridge';
 export * from '../test/generated-wrappers/dex_forwarder_bridge';
 export * from '../test/generated-wrappers/dydx_bridge';

contracts/asset-proxy/tsconfig.json

@@ -6,6 +6,7 @@
         "generated-artifacts/BalancerBridge.json",
         "generated-artifacts/BancorBridge.json",
         "generated-artifacts/ChaiBridge.json",
+        "generated-artifacts/CreamBridge.json",
         "generated-artifacts/CurveBridge.json",
         "generated-artifacts/DexForwarderBridge.json",
         "generated-artifacts/DydxBridge.json",
@@ -58,6 +59,7 @@
         "test/generated-artifacts/BalancerBridge.json",
         "test/generated-artifacts/BancorBridge.json",
         "test/generated-artifacts/ChaiBridge.json",
+        "test/generated-artifacts/CreamBridge.json",
         "test/generated-artifacts/CurveBridge.json",
         "test/generated-artifacts/DexForwarderBridge.json",
         "test/generated-artifacts/DydxBridge.json",