Merge pull request #24 from trader-xyz/feat/no-approvals-for-accepting-nft-bid

No approvals required when taker sells NFT by accepting a bid

Author: johnrjj

src/sdk/v4/NftSwapV4.ts

@@ -1,7 +1,17 @@
-import { Signer, TypedDataSigner } from '@ethersproject/abstract-signer';
-import { BaseProvider, TransactionReceipt } from '@ethersproject/providers';
-import { BigNumber, BigNumberish, ContractTransaction } from 'ethers';
-import { IZeroEx, IZeroEx__factory } from '../../contracts';
+import type { Signer, TypedDataSigner } from '@ethersproject/abstract-signer';
+import type {
+  BaseProvider,
+  TransactionReceipt,
+} from '@ethersproject/providers';
+import type { BigNumberish, ContractTransaction } from 'ethers';
+import { Interface } from '@ethersproject/abi';
+import invariant from 'tiny-invariant';
+import {
+  ERC1155__factory,
+  ERC721__factory,
+  IZeroEx,
+  IZeroEx__factory,
+} from '../../contracts';
 import type {
   ApprovalStatus,
   BaseNftSwap,
@@ -36,9 +46,11 @@ import type {
   SignedNftOrderV4,
   SigningOptions,
 } from './types';
+import {
+  ERC1155_TRANSFER_FROM_DATA,
+  ERC721_TRANSFER_FROM_DATA,
+} from './nft-safe-transfer-from-data';
 import addresses from './addresses.json';
-import invariant from 'tiny-invariant';
-import { NULL_ADDRESS } from '../../utils/eth';
 
 export enum SupportedChainIdsV4 {
   Ropsten = 3,
@@ -364,6 +376,95 @@ class NftSwapV4 implements INftSwapV4 {
     return signedOrder;
   };
 
+  /**
+   * Fill a 'Buy NFT' order (e.g. taker would be selling'their NFT to fill this order) without needing an approval
+   * Use case: Users can accept offers/bids for their NFTs without needing to approve their NFT! 🤯
+   * @param signedOrder Signed Buy Nft order (e.g. direction = 1)
+   * @param tokenId NFT token id that taker of trade will sell
+   * @param fillOrderOverrides Trade specific (SDK-level) overrides
+   * @param transactionOverrides General transaction overrides from ethers (gasPrice, gasLimit, etc)
+   * @returns
+   */
+  fillBuyNftOrderWithoutApproval = async (
+    signedOrder: SignedNftOrderV4,
+    tokenId: string,
+    fillOrderOverrides?: Partial<FillOrderOverrides>,
+    transactionOverrides?: Partial<PayableOverrides>
+  ) => {
+    if (!this.signer) {
+      throw new Error(
+        'Signer undefined. Signer must be provided to fill order'
+      );
+    }
+    if (signedOrder.direction !== TradeDirection.BuyNFT) {
+      throw new Error(
+        'Only filling Buy NFT orders (direction=1) is valid for skipping approvals'
+      );
+    }
+
+    const signerAddress = await this.signer.getAddress();
+    const unwrapWeth =
+      fillOrderOverrides?.fillOrderWithNativeTokenInsteadOfWrappedToken ??
+      false;
+
+    // Handle ERC721
+    if ('erc721Token' in signedOrder) {
+      const erc721Contract = ERC721__factory.connect(
+        signedOrder.erc721Token,
+        this.signer
+      );
+
+      const encodingIface = new Interface(ERC721_TRANSFER_FROM_DATA);
+
+      const fragment = encodingIface.getFunction('safeTransferFromErc721Data');
+      const data = encodingIface._encodeParams(fragment.inputs, [
+        signedOrder,
+        signedOrder.signature,
+        unwrapWeth,
+      ]);
+
+      const transferFromTx = await erc721Contract[
+        'safeTransferFrom(address,address,uint256,bytes)'
+      ](
+        signerAddress,
+        this.exchangeProxy.address,
+        fillOrderOverrides?.tokenIdToSellForCollectionOrder ?? tokenId,
+        data,
+        transactionOverrides ?? {}
+      );
+      return transferFromTx;
+    }
+
+    // Handle ERC1155
+    if ('erc1155Token' in signedOrder) {
+      const erc1155Contract = ERC1155__factory.connect(
+        signedOrder.erc1155Token,
+        this.signer
+      );
+      const encodingIface = new Interface(ERC1155_TRANSFER_FROM_DATA);
+
+      const fragment = encodingIface.getFunction('safeTransferFromErc1155Data');
+      const data = encodingIface._encodeParams(fragment.inputs, [
+        signedOrder,
+        signedOrder.signature,
+        unwrapWeth,
+      ]);
+
+      const transferFromTx = await erc1155Contract.safeTransferFrom(
+        signerAddress,
+        this.exchangeProxy.address,
+        fillOrderOverrides?.tokenIdToSellForCollectionOrder ?? tokenId,
+        signedOrder.erc1155TokenAmount ?? '1',
+        data,
+        transactionOverrides ?? {}
+      );
+      return transferFromTx;
+    }
+
+    // Unknown format (NFT neither ERC721 or ERC1155)
+    throw new Error('unknown order type');
+  };
+
   fillSignedCollectionOrder = async (
     signedOrder: SignedNftOrderV4,
     tokenId: BigNumberish,