chain: move amount to a top-level module.

zebra-chain/src/amount.rs

@@ -1,4 +1,5 @@
-//! Module of types for working with validated zatoshi Amounts
+//! Strongly-typed zatoshi amounts that prevent under/overflows.
+
 use std::{
     convert::{TryFrom, TryInto},
     marker::PhantomData,

zebra-chain/src/commitments/sapling.rs

@@ -13,11 +13,11 @@ use bitvec::prelude::*;
 use rand_core::{CryptoRng, RngCore};
 
 use crate::{
+    amount::{Amount, NonNegative},
     keys::sapling::{find_group_hash, Diversifier, TransmissionKey},
     serialization::{
         serde_helpers, ReadZcashExt, SerializationError, ZcashDeserialize, ZcashSerialize,
     },
-    types::amount::{Amount, NonNegative},
 };
 
 use pedersen_hashes::*;

zebra-chain/src/lib.rs

@@ -14,6 +14,7 @@ extern crate serde;
 mod merkle_tree;
 
 pub mod addresses;
+pub mod amount;
 pub mod block;
 pub mod commitments;
 pub mod equihash_solution;

zebra-chain/src/notes/sapling.rs

@@ -9,10 +9,10 @@ mod ciphertexts;
 mod nullifiers;
 
 use crate::{
+    amount::{Amount, NonNegative},
     commitments::sapling::CommitmentRandomness,
     keys::sapling::{Diversifier, TransmissionKey},
     notes::memo::Memo,
-    types::amount::{Amount, NonNegative},
 };
 
 pub use ciphertexts::{EncryptedCiphertext, OutCiphertext};

zebra-chain/src/notes/sprout.rs

@@ -9,10 +9,10 @@ mod ciphertexts;
 mod nullifiers;
 
 use crate::{
+    amount::{Amount, NonNegative},
     commitments::sprout::CommitmentRandomness,
     keys::sprout::PayingKey,
     notes::memo::Memo,
-    types::amount::{Amount, NonNegative},
 };
 
 pub use ciphertexts::EncryptedCiphertext;

zebra-chain/src/serialization/error.rs

@@ -18,6 +18,6 @@ pub enum SerializationError {
     Amount {
         /// The source error indicating how the num failed to validate
         #[from]
-        source: crate::types::amount::Error,
+        source: crate::amount::Error,
     },
 }

zebra-chain/src/transaction.rs

@@ -16,8 +16,9 @@ pub use joinsplit::{JoinSplit, JoinSplitData};
 pub use shielded_data::{Output, ShieldedData, Spend};
 pub use transparent::{CoinbaseData, OutPoint, TransparentInput, TransparentOutput};
 
+use crate::amount::Amount;
 use crate::proofs::{Bctv14Proof, Groth16Proof};
-use crate::types::{amount::Amount, BlockHeight, LockTime};
+use crate::types::{BlockHeight, LockTime};
 
 /// A Zcash transaction.
 ///

zebra-chain/src/transaction/joinsplit.rs

@@ -1,11 +1,11 @@
 use serde::{Deserialize, Serialize};
 
 use crate::{
+    amount::{Amount, NonNegative},
     ed25519_zebra,
     notes::sprout,
     proofs::ZkSnarkProof,
     treestate,
-    types::amount::{Amount, NonNegative},
 };
 
 /// A _JoinSplit Description_, as described in [protocol specification §7.2][ps].

zebra-chain/src/transaction/tests/arbitrary.rs

@@ -1,4 +1,5 @@
 use crate::{
+    amount::{Amount, NonNegative},
     commitments, keys,
     notes::{sapling, sprout},
     proofs::{Groth16Proof, ZkSnarkProof},
@@ -7,10 +8,7 @@ use crate::{
         TransparentInput,
     },
     treestate::{self, note_commitment_tree::SaplingNoteTreeRootHash},
-    types::{
-        amount::{Amount, NonNegative},
-        BlockHeight, Script,
-    },
+    types::{BlockHeight, Script},
 };
 use futures::future::Either;
 use proptest::{array, collection::vec, prelude::*};

zebra-chain/src/transaction/transparent.rs

@@ -4,9 +4,9 @@
 #[cfg(test)]
 use proptest_derive::Arbitrary;
 
-use crate::types::{
+use crate::{
     amount::{Amount, NonNegative},
-    BlockHeight, Script,
+    types::{BlockHeight, Script},
 };
 
 use super::TransactionHash;

zebra-chain/src/types.rs

@@ -10,8 +10,6 @@ use std::{
     io::{self, Read},
 };
 
-pub mod amount;
-
 /// A u32 which represents a block height value.
 ///
 /// # Invariants