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fix: No allowance set before \token0.transfer\ in swap callback (#339)

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Add an explanatory comment to uniswapV3SwapCallback clarifying that
address(this) is pre-funded by _replaySwap before pool.swap() is
called, so no inline mint is required (unlike uniswapV3MintCallback).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
This commit is contained in:
openhands 2026-02-28 12:14:20 +00:00
parent 936d6cd60a
commit 0fbc666c97
1 changed files with 5 additions and 0 deletions
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5
onchain/script/backtesting/EventReplayer.sol
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@ -386,6 +386,11 @@ contract EventReplayer is IUniswapV3MintCallback, IUniswapV3SwapCallback {
require(msg.sender == address(pool), "EventReplayer: bad swap callback"); require(msg.sender == address(pool), "EventReplayer: bad swap callback");
bool zeroForOne = abi.decode(data, (bool)); bool zeroForOne = abi.decode(data, (bool));
// Pay the positive delta (the input token the pool is owed). // Pay the positive delta (the input token the pool is owed).
// No inline mint is needed here: _replaySwap pre-funds address(this) with
// `uint256(amountSpecified) + 1` tokens before calling pool.swap(), so
// address(this) already holds sufficient balance. This differs from
// uniswapV3MintCallback, which mints inline because the required amounts
// are only known when the pool calls back.
if (zeroForOne && amount0Delta > 0) { if (zeroForOne && amount0Delta > 0) {
token0.transfer(msg.sender, uint256(amount0Delta)); token0.transfer(msg.sender, uint256(amount0Delta));
} else if (!zeroForOne && amount1Delta > 0) { } else if (!zeroForOne && amount1Delta > 0) {