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ERC20CappedLib

Git Source

Title: ERC20CappedLib

Authors: David Dada <daveproxy80@gmail.com> (https://github.com/dadadave80), Modified from OpenZeppelin (https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC20/extensions/ERC20Capped.sol)

Library implementing a capped total supply for ERC-20 tokens.

Ports OpenZeppelin v5.6.1 ERC20Capped. Differences from OpenZeppelin:

  • OpenZeppelin checks the cap in _update, so every mint is capped. Here the cap holds only where a mint path calls _checkCap. The ERC20Capped facet exports only cap(), and its internal _mint is not reachable through a diamond, so a composing mint facet must call _checkCap itself. A mint through ERC20Lib._mint from another facet (ERC7802, ERC20Crosschain, ERC20Wrapper, ERC4626, VaultCore, GovernedVault, ERC20VotesLib._mint, and ERC20FlashMint for the length of a loan) is not capped. Closing this needs a hook in ERC20Lib, which decision D25 on #234 rules out for 0.5.0.
  • _checkCap runs before the mint with the projected supply; OpenZeppelin checks the supply after it. Both revert IERC20Capped.ERC20ExceededCap with the same arguments.
  • Registers IERC20Capped for ERC-165 in its init; OpenZeppelin's extension has no ERC-165. See docs/guides/selector-compatibility.md#token-extension-hook-model.

Functions

erc20CappedStorage

function erc20CappedStorage() internal pure returns (ERC20CappedStorage storage $);

Returns

NameTypeDescription
$ERC20CappedStorage

__ERC20Capped_init

Initializes the ERC-20Capped module with a supply cap.

Must be called inside a pre/postInitializer block. Reverts with ERC20InvalidCap if cap is 0.

 
function __ERC20Capped_init(uint256 cap_) internal;

Parameters

NameTypeDescription
cap_uint256

registerInterface

Registers support for the IERC20Capped interface via ERC-165.

function registerInterface() internal;

cap

Returns the cap on the token's total supply.

 
function cap() internal view returns (uint256);

Returns

NameTypeDescription
<none>uint256

_checkCap

Reverts if newSupply would exceed the cap.

Call this before minting to enforce the cap constraint.

 
function _checkCap(uint256 newSupply) internal view;

Parameters

NameTypeDescription
newSupplyuint256