Create PaymentFailureReason enum

Author: alecchendev

lightning/src/events/mod.rs

@@ -270,6 +270,45 @@ impl_writeable_tlv_based_enum!(InterceptNextHop,
 	};
 );
 
+/// The reason the payment failed. Used in [`Event::PaymentFailed`].
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum PaymentFailureReason {
+	/// The intended recipient rejected our payment.
+	RecipientRejected,
+	/// The user chose to abandon this payment by calling [`ChannelManager::abandon_payment`].
+	///
+	/// [`ChannelManager::abandon_payment`]: crate::ln::channelmanager::ChannelManager::abandon_payment
+	UserAbandoned,
+	/// We exhausted all of our retry attempts while trying to send the payment, or we
+	/// exhausted the [`Retry::Timeout`] if the user set one. If at any point the reason a retry
+	/// attempt failed while being forwarded along the path, a [`Event::PaymentPathFailed`] will
+	/// have come before this.
+	///
+	/// [`Retry::Timeout`]: crate::ln::channelmanager::Retry::Timeout
+	RetriesExhausted,
+	/// The payment expired while retrying. If the user chooses to include an
+	/// [`PaymentParameters::expiry_time`] in their [`PaymentParameters`] this payment will be
+	/// failed if it is retried after this time has elapsed.
+	///
+	/// [`PaymentParameters`]: crate::routing::router::PaymentParameters
+	/// [`PaymentParameters::expiry_time`]: crate::routing::router::PaymentParameters::expiry_time
+	PaymentExpired,
+	/// We failed to find a route while retrying the payment.
+	RouteNotFound,
+	/// This error should generally never happen. This likely means that there is a problem with
+	/// your router.
+	UnexpectedError,
+}
+
+impl_writeable_tlv_based_enum!(PaymentFailureReason,
+	(0, RecipientRejected) => {},
+	(2, UserAbandoned) => {},
+	(4, RetriesExhausted) => {},
+	(6, PaymentExpired) => {},
+	(8, RouteNotFound) => {},
+	(10, UnexpectedError) => {}, ;
+);
+
 /// An Event which you should probably take some action in response to.
 ///
 /// Note that while Writeable and Readable are implemented for Event, you probably shouldn't use