Governance Token

Table of Contents

• Overview
  • Token Minting
  • Token Burning
  • Voting Power
    • Public Query Functions
  • Delegation
    • Basic Delegation

Overview

GovernanceToken is an ERC20 token contract that inherits from ERC20Burnable, ERC20Votes, and Ownable. It allows token holders to delegate their voting power to other addresses, enabling a representative voting system. The GovernanceToken currently only supports basic delegation whereby a user can delegate its entire token balance to a specific address for voting and votes cannot be re-delegated.

Token Minting

GovernanceToken MUST have a mint(address,uint256) function with external visibility that allows the owner() address to mint an arbitrary number of new tokens to a specific address. This function MUST only be called by the contract owner, the MintManager, as enforced by the onlyOwner modifier inherited from the Ownable contract.

Token Burning

The contract MUST allow token holders to burn their own tokens using the inherited burn(uint256) or burnFrom(address,uint256) functions inherited from ERC20Burnable. Burn functions MUST NOT allow a user's balance to underflow and attempts to reduce balance below zero MUST revert.

Voting Power

Each token corresponds to one unit of voting power. Token holders who wish to utilize their tokens for voting MUST delegate their voting power to an address (can be their own address). An active delegation MUST NOT prevent a user from transferring tokens. The GovernanceToken contract MUST offer public accessor functions for querying voting power, as outlined below.

Public Query Functions

• checkpoints(address,uint32) returns (Checkpoint)
  • MUST retrieve the n-th Checkpoint for a given address.
• numCheckpoints(address) returns (uint32)
  • MUST retrieve the total number of Checkpoint objects for a given address.
• delegates(address) returns (address)
  • MUST retrieve the address that an account is delegating to.
• getVotes() returns (uint256)
  • MUST retrieve the current voting power of an address.
• getPastVotes(address,uint256) returns (uint256)
  • MUST retrieve the voting power of an address at specific block number in the past.
• getPastTotalSupply(uint256) returns (uint256)
  • MUST return the total token supply at a specific block number in the past.

Delegation

Basic Delegation

Vote power can be delegated either by calling the delegate(address) function directly (to delegate as the msg.sender) or by providing a signature to be used with function delegateBySig(address,uint256,uint256,uint8,bytes32,bytes32), as inherited from ERC20Votes. Delegation through these functions is considered "basic delegation" as these functions will delegate the entirety of the user's available balance to the target address. Delegations cannot be re-delegated to another address.