fix: incorrect token balance changes for simulations of multiple tokens that include an NFT mint #4290
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Explanation
When simulating a transaction resulting in an NFT mint, we skip the prior owner check for the NFT since the token does not exist yet. However, for subsequent tokens, we were using the incorrect index for the prior balance transaction.
The fix is to keep a separate prevBalanceIndex, which we only increment if a prior balance transaction was included in the simulation.
References
Changelog
@metamask/transaction-controller
Checklist