Use sendAll when change would be dust instead of creating dust change outputs#451
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ben-kaufman wants to merge 2 commits intofeat/multiple-addresses-typesfrom
Open
Use sendAll when change would be dust instead of creating dust change outputs#451ben-kaufman wants to merge 2 commits intofeat/multiple-addresses-typesfrom
ben-kaufman wants to merge 2 commits intofeat/multiple-addresses-typesfrom
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…hange output Use normal fee (recipient + change) instead of sendAll fee when checking if change would be dust. The sendAll fee was for a 1-output tx, causing expectedChange to be overestimated and dust change outputs to be created when sending almost the max amount.
Co-authored-by: Cursor <cursoragent@cursor.com>
jvsena42
reviewed
Feb 20, 2026
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Problem
When sending close to the maximum amount, the app sometimes created dust change outputs instead of using sendAll. This happened because the dust check used the sendAll fee (1-output tx) instead of the normal fee (recipient + change). That overestimated expected change and made the dust check pass when it should not.
Solution
Use the normal fee (recipient + change outputs) when deciding if change would be dust. If change is below the dust limit, use sendAll so the extra amount goes to fees instead of a dust output.
Added DustChangeHelper.shouldUseSendAllToAvoidDust() to centralize the logic.
Added unit tests for the dust-change decision.
Applied in both SendConfirmationView (onchain send) and SpendingConfirm (Blocktank channel purchase).