f Don't try_into

lightning/src/ln/channel.rs

@@ -46,7 +46,6 @@ use crate::io;
 use crate::prelude::*;
 use core::{cmp,mem,fmt};
 use core::ops::Deref;
-use core::convert::TryInto;
 #[cfg(any(test, fuzzing, debug_assertions))]
 use crate::sync::Mutex;
 use bitcoin::hashes::hex::ToHex;
@@ -4532,8 +4531,8 @@ impl<Signer: Sign> Channel<Signer> {
 			// We either haven't seen any confirmation yet, or observed a reorg.
 			return 0;
 		}
-		let funding_tx_confirmations = height as i64 - self.funding_tx_confirmation_height as i64 + 1;
-		funding_tx_confirmations.try_into().unwrap_or(0)
+
+		height.checked_sub(self.funding_tx_confirmation_height).map_or(0, |c| c + 1)
 	}
 
 	fn get_holder_selected_contest_delay(&self) -> u16 {