Remove From implementations for MonitorName

Now that MonitorName can be represented by either an OutPoint for V1
established channels or a ChannelId for V2 established channels, having
a From implementation converting from those types may be misleading.
Remove these implementations since the enum variants are at least
explicit about what version channels the MonitorName is applicable, even
if still possible to create a MonitorName incorrectly.

Author: jkczyz

lightning/src/chain/channelmonitor.rs

@@ -1480,9 +1480,9 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitor<Signer> {
 		let funding_outpoint = inner.first_confirmed_funding_txo;
 		let channel_id = inner.channel_id;
 		if ChannelId::v1_from_funding_outpoint(funding_outpoint) == channel_id {
-			MonitorName::from(funding_outpoint)
+			MonitorName::V1Channel(funding_outpoint)
 		} else {
-			MonitorName::from(channel_id)
+			MonitorName::V2Channel(channel_id)
 		}
 	}
 

lightning/src/util/persist.rs

@@ -911,12 +911,12 @@ where
 ///	 txid: Txid::from_str("deadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeef").unwrap(),
 ///	 index: 1,
 /// };
-/// let monitor_name = MonitorName::from(outpoint);
+/// let monitor_name = MonitorName::V1Channel(outpoint);
 /// assert_eq!(&monitor_name.to_string(), "deadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeef_1");
 ///
 /// // v2 channel
 /// let channel_id = ChannelId(<[u8; 32]>::from_hex("deadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeef").unwrap());
-/// let monitor_name = MonitorName::from(channel_id);
+/// let monitor_name = MonitorName::V2Channel(channel_id);
 /// assert_eq!(&monitor_name.to_string(), "deadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeef");
 ///
 /// // Using MonitorName to generate a storage key
@@ -959,26 +959,6 @@ impl MonitorName {
 	}
 }
 
-impl From<OutPoint> for MonitorName {
-	/// Creates a `MonitorName` from an `OutPoint`.
-	///
-	/// This is typically used when you need to generate a storage key or identifier
-	/// for a new or existing channel monitor for a v1 channel.
-	fn from(outpoint: OutPoint) -> Self {
-		MonitorName::V1Channel(outpoint)
-	}
-}
-
-impl From<ChannelId> for MonitorName {
-	/// Creates a `MonitorName` from a `ChannelId`.
-	///
-	/// This is typically used when you need to generate a storage key or identifier
-	/// for a new or existing channel monitor for a v2 channel.
-	fn from(channel_id: ChannelId) -> Self {
-		MonitorName::V2Channel(channel_id)
-	}
-}
-
 impl core::fmt::Display for MonitorName {
 	fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
 		match self {
@@ -1108,7 +1088,7 @@ mod tests {
 
 	#[test]
 	fn creates_monitor_from_outpoint() {
-		let monitor_name = MonitorName::from(OutPoint {
+		let monitor_name = MonitorName::V1Channel(OutPoint {
 			txid: Txid::from_str(
 				"deadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeef",
 			)
@@ -1119,9 +1099,8 @@ mod tests {
 			&monitor_name.to_string(),
 			"deadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeef_1"
 		);
-		assert!(matches!(monitor_name, MonitorName::V1Channel(_)));
 
-		let monitor_name = MonitorName::from(OutPoint {
+		let monitor_name = MonitorName::V1Channel(OutPoint {
 			txid: Txid::from_str(
 				"f33dbeeff33dbeeff33dbeeff33dbeeff33dbeeff33dbeeff33dbeeff33dbeef",
 			)
@@ -1132,12 +1111,11 @@ mod tests {
 			&monitor_name.to_string(),
 			"f33dbeeff33dbeeff33dbeeff33dbeeff33dbeeff33dbeeff33dbeeff33dbeef_65535"
 		);
-		assert!(matches!(monitor_name, MonitorName::V1Channel(_)));
 	}
 
 	#[test]
 	fn creates_monitor_from_channel_id() {
-		let monitor_name = MonitorName::from(ChannelId(
+		let monitor_name = MonitorName::V2Channel(ChannelId(
 			<[u8; 32]>::from_hex(
 				"deadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeef",
 			)
@@ -1147,7 +1125,6 @@ mod tests {
 			&monitor_name.to_string(),
 			"deadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeefdeadbeef"
 		);
-		assert!(matches!(monitor_name, MonitorName::V2Channel(_)));
 	}
 
 	#[test]
@@ -1234,7 +1211,7 @@ mod tests {
 					// check that when we read it, we got the right update id
 					assert_eq!(mon.get_latest_update_id(), $expected_update_id);
 
-					let monitor_name = MonitorName::from(mon.get_funding_txo());
+					let monitor_name = mon.persistence_key();
 					assert_eq!(
 						persister_0
 							.kv_store
@@ -1253,7 +1230,7 @@ mod tests {
 				assert_eq!(persisted_chan_data_1.len(), 1);
 				for (_, mon) in persisted_chan_data_1.iter() {
 					assert_eq!(mon.get_latest_update_id(), $expected_update_id);
-					let monitor_name = MonitorName::from(mon.get_funding_txo());
+					let monitor_name = mon.persistence_key();
 					assert_eq!(
 						persister_1
 							.kv_store
@@ -1449,7 +1426,7 @@ mod tests {
 		// Get the monitor and make a fake stale update at update_id=1 (lowest height of an update possible)
 		let persisted_chan_data = persister_0.read_all_channel_monitors_with_updates().unwrap();
 		let (_, monitor) = &persisted_chan_data[0];
-		let monitor_name = MonitorName::from(monitor.get_funding_txo());
+		let monitor_name = monitor.persistence_key();
 		persister_0
 			.kv_store
 			.write(