Swapper

GitHub: link

Abstract contract for swapping between xPYTs/NYTs and their underlying asset by swapping via an external DEX and minting/burning xPYT/NYT.

Swapper supports two-hop swaps where one of the swaps is an 0x swap between two regular tokens, which enables swapping any supported token into any xPYT/NYT. Two-hop swaps are done by chaining two calls together via Multicall and setting the recipient of the first swap to the Swapper.

Errors

Error_SameToken

error Error_SameToken()

Error_PastDeadline

error Error_PastDeadline()

Error_ZeroExSwapFailed

error Error_ZeroExSwapFailed()

Error_InsufficientOutput

error Error_InsufficientOutput()

Error_ProtocolFeeRecipientIsZero

error Error_ProtocolFeeRecipientIsZero()

Events

SetProtocolFee

event SetProtocolFee(struct Swapper.ProtocolFeeInfo protocolFeeInfo_)

Structs

SwapArgs

struct SwapArgs {
  contract Gate gate;
  address vault;
  contract ERC20 underlying;
  contract ERC20 nyt;
  contract ERC20 pyt;
  contract IxPYT xPYT;
  uint256 tokenAmountIn;
  uint256 minAmountOut;
  address recipient;
  bool useSwapperBalance;
  bool usePYT;
  uint256 deadline;
  bytes extraArgs;
}

ProtocolFeeInfo

struct ProtocolFeeInfo {
  uint8 fee;
  address recipient;
}

Immutable parameters

zeroExProxy

address zeroExProxy

The 0x proxy contract used for 0x swaps

weth

contract WETH weth

The Wrapped Ethereum contract

State variables

protocolFeeInfo

struct Swapper.ProtocolFeeInfo protocolFeeInfo

The protocol fee and the fee recipient address.

State-mutating functions

swapUnderlyingToNyt

function swapUnderlyingToNyt(struct Swapper.SwapArgs args) external virtual returns (uint256 tokenAmountOut)

Swaps the underlying asset of an NYT into the NYT

Name	Type	Description
args	struct Swapper.SwapArgs	The input arguments (see SwapArgs definition)

Name	Type	Description
tokenAmountOut	uint256	The amount of token output

swapUnderlyingToXpyt

function swapUnderlyingToXpyt(struct Swapper.SwapArgs args) external virtual returns (uint256 tokenAmountOut)

Swaps the underlying asset of an xPYT into the xPYT

Name	Type	Description
args	struct Swapper.SwapArgs	The input arguments (see SwapArgs definition)

Name	Type	Description
tokenAmountOut	uint256	The amount of token output

swapNytToUnderlying

function swapNytToUnderlying(struct Swapper.SwapArgs args) external virtual returns (uint256 tokenAmountOut)

Swaps an NYT to its underlying asset

Name	Type	Description
args	struct Swapper.SwapArgs	The input arguments (see SwapArgs definition)

Name	Type	Description
tokenAmountOut	uint256	The amount of token output

swapXpytToUnderlying

function swapXpytToUnderlying(struct Swapper.SwapArgs args) external virtual returns (uint256 tokenAmountOut)

Swaps an xPYT to its underlying asset

Name	Type	Description
args	struct Swapper.SwapArgs	The input arguments (see SwapArgs definition)

Name	Type	Description
tokenAmountOut	uint256	The amount of token output

doZeroExSwap

function doZeroExSwap(contract ERC20 tokenIn, uint256 tokenAmountIn, contract ERC20 tokenOut, uint256 minAmountOut, address recipient, bool useSwapperBalance, bool requireApproval, uint256 deadline, bytes swapData) external virtual returns (uint256 tokenAmountOut)

Swaps between two regular tokens using 0x.

Used in conjuction with the 0x API https://www.0x.org/docs/api

Name	Type	Description
tokenIn	contract ERC20	The input token
tokenAmountIn	uint256	The amount of token input
tokenOut	contract ERC20	The output token
minAmountOut	uint256	The minimum acceptable token output amount, used for slippage checking.
recipient	address	The recipient of the token output
useSwapperBalance	bool	Set to true to use the Swapper's token balance as token input
requireApproval	bool	Set to true to approve tokenIn to zeroExProxy
deadline	uint256	The Unix timestamp (in seconds) after which the call will be reverted
swapData	bytes	The call data to zeroExProxy to execute the swap, obtained from the https://api.0x.org/swap/v1/quote endpoint

Name	Type	Description
tokenAmountOut	uint256	The amount of token output

wrapEthInput

function wrapEthInput() external payable

Wraps the user's ETH input into WETH

Should be used as part of a multicall to convert the user's ETH input into WETH so that it can be swapped into xPYT/NYT.

Owner functions

ownerSetProtocolFee

function ownerSetProtocolFee(struct Swapper.ProtocolFeeInfo protocolFeeInfo_) external virtual

Updates the protocol fee and/or the protocol fee recipient. Only callable by the owner.

Name	Type	Description
protocolFeeInfo_	struct Swapper.ProtocolFeeInfo	The new protocol fee info