X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fln%2Ffeatures.rs;h=8f251d8478c7048f33cfb003725f4c94b388a209;hb=7dd8bd7068fdaab3c83e152b304086e1c363e999;hp=b90748aa87b7e5cd55bf0461244fd2c654feb7eb;hpb=f3b63e4dab439166827c1d9f144db1abc824d6ec;p=rust-lightning

diff --git a/lightning/src/ln/features.rs b/lightning/src/ln/features.rs
index b90748aa..8f251d84 100644
--- a/lightning/src/ln/features.rs
+++ b/lightning/src/ln/features.rs
@@ -22,8 +22,10 @@
 //! [BOLT #9]: https://github.com/lightningnetwork/lightning-rfc/blob/master/09-features.md
 //! [messages]: crate::ln::msgs
 
+use io;
 use prelude::*;
 use core::{cmp, fmt};
+use core::hash::{Hash, Hasher};
 use core::marker::PhantomData;
 
 use bitcoin::bech32;
@@ -361,6 +363,11 @@ impl<T: sealed::Context> Clone for Features<T> {
 		}
 	}
 }
+impl<T: sealed::Context> Hash for Features<T> {
+	fn hash<H: Hasher>(&self, hasher: &mut H) {
+		self.flags.hash(hasher);
+	}
+}
 impl<T: sealed::Context> PartialEq for Features<T> {
 	fn eq(&self, o: &Self) -> bool {
 		self.flags.eq(&o.flags)
@@ -383,9 +390,8 @@ pub type InvoiceFeatures = Features<sealed::InvoiceContext>;
 
 impl InitFeatures {
 	/// Writes all features present up to, and including, 13.
-	pub(crate) fn write_up_to_13<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+	pub(crate) fn write_up_to_13<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 		let len = cmp::min(2, self.flags.len());
-		w.size_hint(len + 2);
 		(len as u16).write(w)?;
 		for i in (0..len).rev() {
 			if i == 0 {
@@ -547,7 +553,9 @@ impl<T: sealed::Context> Features<T> {
 		&self.flags
 	}
 
-	pub(crate) fn requires_unknown_bits(&self) -> bool {
+	/// Returns true if this `Features` object contains unknown feature flags which are set as
+	/// "required".
+	pub fn requires_unknown_bits(&self) -> bool {
 		// Bitwise AND-ing with all even bits set except for known features will select required
 		// unknown features.
 		let byte_count = T::KNOWN_FEATURE_MASK.len();
@@ -575,12 +583,6 @@ impl<T: sealed::Context> Features<T> {
 			(byte & unknown_features) != 0
 		})
 	}
-
-	/// The number of bytes required to represent the feature flags present. This does not include
-	/// the length bytes which are included in the serialized form.
-	pub(crate) fn byte_count(&self) -> usize {
-		self.flags.len()
-	}
 }
 
 impl<T: sealed::DataLossProtect> Features<T> {
@@ -692,8 +694,7 @@ impl<T: sealed::ShutdownAnySegwit> Features<T> {
 }
 
 impl<T: sealed::Context> Writeable for Features<T> {
-	fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
-		w.size_hint(self.flags.len() + 2);
+	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 		(self.flags.len() as u16).write(w)?;
 		for f in self.flags.iter().rev() { // Swap back to big-endian
 			f.write(w)?;
@@ -703,7 +704,7 @@ impl<T: sealed::Context> Writeable for Features<T> {
 }
 
 impl<T: sealed::Context> Readable for Features<T> {
-	fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
+	fn read<R: io::Read>(r: &mut R) -> Result<Self, DecodeError> {
 		let mut flags: Vec<u8> = Readable::read(r)?;
 		flags.reverse(); // Swap to little-endian
 		Ok(Self {
@@ -826,7 +827,7 @@ mod tests {
 	#[test]
 	fn convert_to_context_with_unknown_flags() {
 		// Ensure the `from` context has fewer known feature bytes than the `to` context.
-		assert!(InvoiceFeatures::known().byte_count() < NodeFeatures::known().byte_count());
+		assert!(InvoiceFeatures::known().flags.len() < NodeFeatures::known().flags.len());
 		let invoice_features = InvoiceFeatures::known().set_unknown_feature_optional();
 		assert!(invoice_features.supports_unknown_bits());
 		let node_features: NodeFeatures = invoice_features.to_context();