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Merge branch 'master' into solc-0.7

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This commit is contained in:
Francisco Giordano
2020-08-24 18:14:25 -03:00
parent 48072e439d 1f06fd7e66
commit 89e2b7424b
13 changed files with 589 additions and 372 deletions
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37
contracts/token/ERC20/ERC20Snapshot.sol
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@ -104,28 +104,25 @@ abstract contract ERC20Snapshot is ERC20 {
return snapshotted ? value : totalSupply();
}
// _transfer, _mint and _burn are the only functions where the balances are modified, so it is there that the
// snapshots are updated. Note that the update happens _before_ the balance change, with the pre-modified value.
// The same is true for the total supply and _mint and _burn.
function _transfer(address from, address to, uint256 value) internal virtual override {
// Update balance and/or total supply snapshots before the values are modified. This is implemented
// in the _beforeTokenTransfer hook, which is executed for _mint, _burn, and _transfer operations.
function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual override {
super._beforeTokenTransfer(from, to, amount);
if (from == address(0)) {
// mint
_updateAccountSnapshot(to);
_updateTotalSupplySnapshot();
} else if (to == address(0)) {
// burn
_updateAccountSnapshot(from);
_updateTotalSupplySnapshot();
} else {
// transfer
_updateAccountSnapshot(from);
_updateAccountSnapshot(to);
super._transfer(from, to, value);
}
function _mint(address account, uint256 value) internal virtual override {
_updateAccountSnapshot(account);
_updateTotalSupplySnapshot();
super._mint(account, value);
}
function _burn(address account, uint256 value) internal virtual override {
_updateAccountSnapshot(account);
_updateTotalSupplySnapshot();
super._burn(account, value);
}
}
function _valueAt(uint256 snapshotId, Snapshots storage snapshots)