get rid of unneeded errors

Author: futurepaul

lightning-invoice/src/de.rs

@@ -556,34 +556,24 @@ impl FromBase32 for Fallback {
 					return Err(ParseError::InvalidSegWitProgramLength);
 				}
 
-				let version = match WitnessVersion::try_from(version) {
-					Ok(version) => version,
-					Err(_) => return Err(ParseError::InvalidSegWitVersion),
-				};
-
+				let version = WitnessVersion::try_from(version).expect("0 through 16 are valid SegWit versions");
 				Ok(Fallback::SegWitProgram {
 					version: version,
 					program: bytes
 				})
 			},
 			17 => {
-				if bytes.len() != 20 {
-					return Err(ParseError::InvalidPubKeyHashLength);
-				}
 				let pkh = match PubkeyHash::from_slice(&bytes) {
 					Ok(pkh) => pkh,
-					Err(_) => return Err(ParseError::InvalidPubKeyHash),
+					Err(bitcoin_hashes::Error::InvalidLength(_, _)) => return Err(ParseError::InvalidPubKeyHashLength),
 				};
 
 				Ok(Fallback::PubKeyHash(pkh))
 			}
 			18 => {
-				if bytes.len() != 20 {
-					return Err(ParseError::InvalidScriptHashLength);
-				}
 				let sh = match ScriptHash::from_slice(&bytes) {
 					Ok(sh) => sh,
-					Err(_) => return Err(ParseError::InvalidScriptHash),
+					Err(bitcoin_hashes::Error::InvalidLength(_, _)) => return Err(ParseError::InvalidScriptHashLength),
 				};
 
 				Ok(Fallback::ScriptHash(sh))
@@ -668,21 +658,12 @@ impl Display for ParseError {
 			ParseError::InvalidSegWitProgramLength => {
 				f.write_str("fallback SegWit program is too long or too short")
 			},
-			ParseError::InvalidSegWitVersion => {
-				f.write_str("fallback SegWit version is not valid")
-			},
 			ParseError::InvalidPubKeyHashLength => {
 				f.write_str("fallback public key hash has a length unequal 20 bytes")
 			},
-			ParseError::InvalidPubKeyHash => {
-				f.write_str("fallback public key hash is not a valid")
-			},
 			ParseError::InvalidScriptHashLength => {
 				f.write_str("fallback script hash has a length unequal 32 bytes")
 			},
-			ParseError::InvalidScriptHash => {
-				f.write_str("fallback script hash is not a valid")
-			},
 			ParseError::InvalidRecoveryId => {
 				f.write_str("recovery id is out of range (should be in [0,3])")
 			},

lightning-invoice/src/lib.rs

@@ -122,11 +122,8 @@ pub enum ParseError {
 	PaddingError,
 	IntegerOverflowError,
 	InvalidSegWitProgramLength,
-	InvalidSegWitVersion,
 	InvalidPubKeyHashLength,
-	InvalidPubKeyHash,
 	InvalidScriptHashLength,
-	InvalidScriptHash,
 	InvalidRecoveryId,
 	InvalidSliceLength(String),
 
@@ -1263,8 +1260,6 @@ impl Invoice {
 	///
 	/// (C-not exported) as we don't support Vec<&NonOpaqueType>
 	pub fn fallbacks(&self) -> Vec<&Fallback> {
-
-
 		self.signed_invoice.fallbacks()
 	}
 
@@ -1284,10 +1279,10 @@ impl Invoice {
 					Script::new_witness_program(*version, program.as_slice())
 				}
 				Fallback::PubKeyHash(pkh) => {
-					Script::new_p2pkh(&pkh)
+					Script::new_p2pkh(pkh)
 				}
 				Fallback::ScriptHash(sh) => {
-					Script::new_p2sh(&sh)
+					Script::new_p2sh(sh)
 				}
 			};
 

lightning-invoice/src/ser.rs

@@ -329,7 +329,7 @@ impl ToBase32 for Fallback {
 	fn write_base32<W: WriteBase32>(&self, writer: &mut W) -> Result<(), <W as WriteBase32>::Err> {
 		match *self {
 			Fallback::SegWitProgram {version: v, program: ref p} => {
-				writer.write_u5(u5::try_from_u8(v.to_num()).expect("0-16 < 32"))?;
+				writer.write_u5(Into::<u5>::into(v))?;
 				p.write_base32(writer)
 			},
 			Fallback::PubKeyHash(ref hash) => {