Fix BOLT11 DuplicatePayment triggering on-chain fallback in unified payment - #1038
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Fix BOLT11 DuplicatePayment triggering on-chain fallback in unified payment#1038elnafateh wants to merge 2 commits into
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In `UnifiedPayment::send`, the BOLT11 leg's `bolt11_invoice.send` only returns `Err(PersistenceFailed)` *after* `pay_for_bolt11_invoice` has already succeeded and the Lightning payment is in-flight. The previous match treated every error (via `Err(e)`) as a fall-through to the next payment method, so a persistence failure after initiation would broadcast an on-chain transaction for the same URI — a duplicate payment. We now treat `Err(Error::PersistenceFailed)` on the BOLT11 leg as terminal, mirroring how `DuplicatePayment` is already handled, and abort the unified payment instead of falling back to on-chain. This is a regression hazard raised during review of the lightningdevkit#1033 fix (PR lightningdevkit#1038). It is pre-existing and orthogonal to lightningdevkit#1033 (which only made `DuplicatePayment` terminal); tracked separately as the unified variant of the broader post-commit persistence hazard. Adds `unified_send_bolt11_persistence_failure_no_onchain_fallback`, which arms a failing payment-store write on a `KVStore`-backed node and asserts that `send` returns `PersistenceFailed` without recording any on-chain payment. Co-Authored-By: Claude <noreply@anthropic.com>
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In `UnifiedPayment::send`, the BOLT11 leg's `bolt11_invoice.send` only returns `Err(PersistenceFailed)` *after* `pay_for_bolt11_invoice` has already succeeded and the Lightning payment is in-flight. The previous match treated every error (via `Err(e)`) as a fall-through to the next payment method, so a persistence failure after initiation would broadcast an on-chain transaction for the same URI — a duplicate payment. We now treat `Err(Error::PersistenceFailed)` on the BOLT11 leg as terminal, mirroring how `DuplicatePayment` is already handled, and abort the unified payment instead of falling back to on-chain. This is a regression hazard raised during review of the lightningdevkit#1033 fix (PR lightningdevkit#1038). It is pre-existing and orthogonal to lightningdevkit#1033 (which only made `DuplicatePayment` terminal); tracked separately as the unified variant of the broader post-commit persistence hazard. Adds `unified_send_bolt11_persistence_failure_no_onchain_fallback`, which arms a failing payment-store write on a `KVStore`-backed node and asserts that `send` returns `PersistenceFailed` without recording any on-chain payment.
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You want to make sure each commit compiles, passes tests and is rustfmt'ed.
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There is a lot of test code added. Isn't there a more compact way to cover this?
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Got it! Extracted the shared node and collapsed the duplicate arms.
…ayments UnifiedPayment::send previously treated any error from the BOLT11 leg of a unified payment as non-terminal and fell through to the on-chain payment method. This meant a retried BOLT11 payment that returns Error::DuplicatePayment would still result in an on-chain transaction being broadcast for the same invoice — a duplicate payment. Error::DuplicatePayment is now terminal in UnifiedPayment::send: the unified payment aborts instead of falling back to on-chain. Fixes lightningdevkit#1033. Adds a regression test, unified_send_bolt11_duplicate_payment_no_onchain_fallback, along with fund_and_open_ready_channel(), wait_for_node_announcement(), and receive_bolt11_only_uri() test helpers reused by the PersistenceFailed regression test in the next commit.
In UnifiedPayment::send, the BOLT11 leg's bolt11_invoice.send only returns Err(PersistenceFailed) *after* pay_for_bolt11_invoice has already succeeded and the Lightning payment is in-flight. The previous match treated every remaining error as a fall-through to the next payment method, so a persistence failure after initiation would broadcast an on-chain transaction for the same URI — a duplicate payment. Err(Error::PersistenceFailed) on the BOLT11 leg is now terminal, mirroring how DuplicatePayment is handled, and aborts the unified payment instead of falling back to on-chain. This is a regression hazard raised during review of the DuplicatePayment fix (PR lightningdevkit#1038). It is pre-existing and orthogonal to lightningdevkit#1033; tracked here as the unified variant of the broader post-commit persistence hazard. Adds PaymentFailingStore, a KVStore wrapper that fails writes to the payments namespace on demand, and a regression test, unified_send_bolt11_persistence_failure_no_onchain_fallback, which arms it and asserts send() returns PersistenceFailed without recording an on-chain payment. Reuses the fund_and_open_ready_channel(), wait_for_node_announcement(), and receive_bolt11_only_uri() helpers from the previous commit.
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UnifiedPayment::sendpreviously fell back to the on-chain method after anyBOLT11 error, including
Error::DuplicatePayment. Retrying a unified BIP21payment could pay the recipient twice — once over Lightning, once on-chain.
Error::DuplicatePaymentis now treated as terminal and returned to thecaller immediately, preventing the unsafe fallback.
Adds an integration test covering the retry scenario.
#1033