Add a macro for creating custom TLVs in tests

Author: alecchendev

lightning/src/util/ser_macros.rs

@@ -141,6 +141,22 @@ macro_rules! encode_tlv_stream {
 	} }
 }
 
+/// Serializes a TLV stream and returns a vector a bytes.
+/// This is exported for use in custom TLV tests, do not use directly.
+#[doc(hidden)]
+#[macro_export]
+macro_rules! _get_encoded_tlv_stream {
+	({$(($type: expr, $field: expr, $fieldty: tt)),* $(,)*}) => { {
+		let mut tlvs = Vec::new();
+		let mut write_tlvs = || -> Result<(), $crate::io::Error> {
+			encode_tlv_stream!(&mut tlvs, {$(($type, $field, $fieldty)),*});
+			Ok(())
+		};
+		write_tlvs().unwrap();
+		tlvs
+	} }
+}
+
 /// Adds the length of the serialized field to a [`LengthCalculatingWriter`].
 /// This is exported for use by other exported macros, do not use directly.
 ///