Increased the generality of Builder struct implementations. Made Sapl…

…ing Builder views stricter.

masp_primitives/src/transaction/builder.rs

@@ -128,7 +128,7 @@ pub struct Builder<P, R, Key = ExtendedSpendingKey, Notifier = Sender<Progress>>
     progress_notifier: Option<Notifier>,
 }
 
-impl<P, R> Builder<P, R> {
+impl<P, R, K, N> Builder<P, R, K, N> {
     /// Returns the network parameters that the builder has been configured for.
     pub fn params(&self) -> &P {
         &self.params

masp_primitives/src/transaction/components/sapling/builder.rs

@@ -103,16 +103,18 @@ impl<Key: BorshDeserialize> BorshDeserialize for SpendDescriptionInfo<Key> {
     }
 }
 
-impl fees::InputView<()> for SpendDescriptionInfo {
+impl<K> fees::InputView<()> for SpendDescriptionInfo<K> {
     fn note_id(&self) -> &() {
         // The builder does not make use of note identifiers, so we can just return the unit value.
         &()
     }
 
-    fn value(&self) -> Amount {
-        // An existing note to be spent must have a valid amount value.
-        Amount::from_pair(self.note.asset_type, self.note.value)
-            .expect("Existing note value with invalid asset type or value.")
+    fn value(&self) -> u64 {
+        self.note.value
+    }
+
+    fn asset_type(&self) -> AssetType {
+        self.note.asset_type
     }
 }
 
@@ -198,9 +200,12 @@ impl SaplingOutputInfo {
 }
 
 impl fees::OutputView for SaplingOutputInfo {
-    fn value(&self) -> Amount {
-        Amount::from_pair(self.note.asset_type, self.note.value)
-            .expect("Note values should be checked at construction.")
+    fn value(&self) -> u64 {
+        self.note.value
+    }
+
+    fn asset_type(&self) -> AssetType {
+        self.note.asset_type
     }
 }
 
@@ -328,7 +333,7 @@ impl Authorization for Unauthorized {
     type AuthSig = SpendDescriptionInfo;
 }
 
-impl<P> SaplingBuilder<P> {
+impl<P, K> SaplingBuilder<P, K> {
     pub fn new(params: P, target_height: BlockHeight) -> Self {
         SaplingBuilder {
             params,

masp_primitives/src/transaction/components/sapling/fees.rs

@@ -1,20 +1,24 @@
 //! Types related to computation of fees and change related to the Sapling components
 //! of a transaction.
 
-use crate::transaction::components::amount::Amount;
+use crate::asset_type::AssetType;
 
 /// A trait that provides a minimized view of a Sapling input suitable for use in
 /// fee and change calculation.
 pub trait InputView<NoteRef> {
     /// An identifier for the input being spent.
     fn note_id(&self) -> &NoteRef;
     /// The value of the input being spent.
-    fn value(&self) -> Amount;
+    fn value(&self) -> u64;
+    /// The asset type of the input being spent.
+    fn asset_type(&self) -> AssetType;
 }
 
 /// A trait that provides a minimized view of a Sapling output suitable for use in
 /// fee and change calculation.
 pub trait OutputView {
     /// The value of the output being produced.
-    fn value(&self) -> Amount;
+    fn value(&self) -> u64;
+    /// The asset type of the output being produced.
+    fn asset_type(&self) -> AssetType;
 }

masp_primitives/src/transaction/components/transparent/fees.rs

@@ -2,7 +2,8 @@
 //! of a transaction.
 
 use super::TxOut;
-use crate::transaction::{components::amount::Amount, TransparentAddress};
+use crate::transaction::TransparentAddress;
+use crate::asset_type::AssetType;
 
 /// This trait provides a minimized view of a transparent input suitable for use in
 /// fee and change computation.
@@ -15,14 +16,20 @@ pub trait InputView {
 /// fee and change computation.
 pub trait OutputView {
     /// Returns the value of the output being created.
-    fn value(&self) -> Amount;
+    fn value(&self) -> i64;
+    /// Returns the asset type of the output being created.
+    fn asset_type(&self) -> AssetType;
     /// Returns the script corresponding to the newly created output.
     fn transparent_address(&self) -> &TransparentAddress;
 }
 
 impl OutputView for TxOut {
-    fn value(&self) -> Amount {
-        Amount::from_pair(self.asset_type, self.value).unwrap()
+    fn value(&self) -> i64 {
+        self.value
+    }
+
+    fn asset_type(&self) -> AssetType {
+        self.asset_type
     }
 
     fn transparent_address(&self) -> &TransparentAddress {