PayoutHelperLib

Library for validating binary outcome payout arrays

Overview

PayoutHelperLib provides validation utilities for payout arrays in the UMA CTF Adapter. It ensures that payout structures conform to the expected binary outcome format.

Source: src/libraries/PayoutHelperLib.sol

Functions

isValidPayoutArray

function isValidPayoutArray(
    uint256[] memory payouts
) internal pure returns (bool)

Validates whether a payout array conforms to the expected format for binary outcomes.

Parameters:

• payouts (uint256[]): The payout array to validate

Returns:

• (bool): true if the payout array is valid, false otherwise

Validation Rules:

A valid payout array must:

1. Have exactly 2 elements - Binary outcomes require exactly two payout values
2. Match one of the following patterns:
   • [1, 0] - Full payout to the first outcome
   • [0, 1] - Full payout to the second outcome
   • [1, 1] - Equal payout to both outcomes (tie/indeterminate)

Invalid Patterns:

• [0, 0] - No payout to either outcome (invalid)
• Arrays with length != 2
• Any values other than 0 or 1

Usage Example

import { PayoutHelperLib } from "./libraries/PayoutHelperLib.sol";

contract Example {
    using PayoutHelperLib for *;
    
    function validatePayout(uint256[] memory payouts) public pure returns (bool) {
        require(
            PayoutHelperLib.isValidPayoutArray(payouts),
            "Invalid payout array"
        );
        return true;
    }
    
    function exampleUsage() public pure {
        uint256[] memory validPayout1 = new uint256[](2);
        validPayout1[0] = 1;
        validPayout1[1] = 0;
        // Returns true
        
        uint256[] memory validPayout2 = new uint256[](2);
        validPayout2[0] = 0;
        validPayout2[1] = 1;
        // Returns true
        
        uint256[] memory validPayout3 = new uint256[](2);
        validPayout3[0] = 1;
        validPayout3[1] = 1;
        // Returns true
        
        uint256[] memory invalidPayout = new uint256[](2);
        invalidPayout[0] = 0;
        invalidPayout[1] = 0;
        // Returns false
    }
}

Binary Outcome Context

This library is designed specifically for binary prediction markets where:

• Each market has two possible outcomes
• Payouts are represented as normalized values (0 or 1)
• A payout of [1, 0] means the first outcome wins
• A payout of [0, 1] means the second outcome wins
• A payout of [1, 1] represents an indeterminate result or tie