add(consensus/network): Add an empty Parameters struct in Network::Testnet

zebra-chain/src/block/tests/vectors.rs

@@ -202,7 +202,7 @@ fn block_test_vectors_height_mainnet() {
 fn block_test_vectors_height_testnet() {
     let _init_guard = zebra_test::init();
 
-    block_test_vectors_height(Testnet);
+    block_test_vectors_height(Network::new_default_testnet());
 }
 
 /// Test that the block test vector indexes match the heights in the block data,
@@ -245,7 +245,7 @@ fn block_commitment_mainnet() {
 fn block_commitment_testnet() {
     let _init_guard = zebra_test::init();
 
-    block_commitment(Testnet);
+    block_commitment(Network::new_default_testnet());
 }
 
 /// Check that the block commitment field parses without errors.

zebra-chain/src/history_tree.rs

@@ -372,8 +372,8 @@ impl NonEmptyHistoryTree {
     }
 
     /// Return the network where this tree is used.
-    pub fn network(&self) -> Network {
-        self.network.clone()
+    pub fn network(&self) -> &Network {
+        &self.network
     }
 }
 

zebra-chain/src/history_tree/tests/vectors.rs

@@ -22,10 +22,10 @@ use eyre::Result;
 /// higher level API.
 #[test]
 fn push_and_prune() -> Result<()> {
-    push_and_prune_for_network_upgrade(Network::Mainnet, NetworkUpgrade::Heartwood)?;
-    push_and_prune_for_network_upgrade(Network::Testnet, NetworkUpgrade::Heartwood)?;
-    push_and_prune_for_network_upgrade(Network::Mainnet, NetworkUpgrade::Canopy)?;
-    push_and_prune_for_network_upgrade(Network::Testnet, NetworkUpgrade::Canopy)?;
+    for network in Network::iter() {
+        push_and_prune_for_network_upgrade(network.clone(), NetworkUpgrade::Heartwood)?;
+        push_and_prune_for_network_upgrade(network, NetworkUpgrade::Canopy)?;
+    }
     Ok(())
 }
 
@@ -109,8 +109,9 @@ fn push_and_prune_for_network_upgrade(
 fn upgrade() -> Result<()> {
     // The history tree only exists Hearwood-onward, and the only upgrade for which
     // we have vectors since then is Canopy. Therefore, only test the Heartwood->Canopy upgrade.
-    upgrade_for_network_upgrade(Network::Mainnet, NetworkUpgrade::Canopy)?;
-    upgrade_for_network_upgrade(Network::Testnet, NetworkUpgrade::Canopy)?;
+    for network in Network::iter() {
+        upgrade_for_network_upgrade(network, NetworkUpgrade::Canopy)?;
+    }
     Ok(())
 }
 

zebra-chain/src/parameters.rs

@@ -21,7 +21,7 @@ mod transaction;
 pub mod arbitrary;
 
 pub use genesis::*;
-pub use network::Network;
+pub use network::{testnet, Network, NetworkKind};
 pub use network_upgrade::*;
 pub use transaction::*;
 

zebra-chain/src/parameters/network.rs

@@ -1,14 +1,18 @@
 //! Consensus parameters for each Zcash network.
 
-use std::{fmt, str::FromStr};
+use std::{fmt, str::FromStr, sync::Arc};
 
 use thiserror::Error;
 
+use zcash_primitives::constants;
+
 use crate::{
     block::{self, Height, HeightDiff},
     parameters::NetworkUpgrade::Canopy,
 };
 
+pub mod testnet;
+
 #[cfg(any(test, feature = "proptest-impl"))]
 use proptest_derive::Arbitrary;
 
@@ -51,52 +55,102 @@ mod tests;
 /// after the grace period.
 const ZIP_212_GRACE_PERIOD_DURATION: HeightDiff = 32_256;
 
+/// An enum describing the kind of network, whether it's the production mainnet or a testnet.
+// Note: The order of these variants is important for correct bincode (de)serialization
+//       of history trees in the db format.
+// TODO: Replace bincode (de)serialization of `HistoryTreeParts` in a db format upgrade?
+#[derive(Copy, Clone, Default, Debug, Eq, PartialEq, Hash, Serialize, Deserialize)]
+pub enum NetworkKind {
+    /// The production mainnet.
+    #[default]
+    Mainnet,
+
+    /// A test network.
+    Testnet,
+
+    /// Regtest mode, not yet implemented
+    // TODO: Add `new_regtest()` and `is_regtest` methods on `Network`.
+    Regtest,
+}
+
+impl From<Network> for NetworkKind {
+    fn from(network: Network) -> Self {
+        network.kind()
+    }
+}
+
 /// An enum describing the possible network choices.
-#[derive(Clone, Debug, Default, Eq, PartialEq, Hash, Serialize, Deserialize)]
+#[derive(Clone, Debug, Default, Eq, PartialEq, Hash, Serialize)]
 #[cfg_attr(any(test, feature = "proptest-impl"), derive(Arbitrary))]
+#[serde(into = "NetworkKind")]
 pub enum Network {
     /// The production mainnet.
     #[default]
     Mainnet,
 
-    /// The oldest public test network.
-    Testnet,
+    /// A test network such as the default public testnet,
+    /// a configured testnet, or Regtest.
+    Testnet(Arc<testnet::Parameters>),
 }
 
-use zcash_primitives::consensus::{Network as ZcashPrimitivesNetwork, Parameters as _};
-impl Network {
+impl NetworkKind {
     /// Returns the human-readable prefix for Base58Check-encoded transparent
     /// pay-to-public-key-hash payment addresses for the network.
-    pub fn b58_pubkey_address_prefix(&self) -> [u8; 2] {
-        <ZcashPrimitivesNetwork>::from(self).b58_pubkey_address_prefix()
+    pub fn b58_pubkey_address_prefix(self) -> [u8; 2] {
+        match self {
+            Self::Mainnet => constants::mainnet::B58_PUBKEY_ADDRESS_PREFIX,
+            Self::Testnet | Self::Regtest => constants::testnet::B58_PUBKEY_ADDRESS_PREFIX,
+        }
     }
 
     /// Returns the human-readable prefix for Base58Check-encoded transparent pay-to-script-hash
     /// payment addresses for the network.
-    pub fn b58_script_address_prefix(&self) -> [u8; 2] {
-        <ZcashPrimitivesNetwork>::from(self).b58_script_address_prefix()
-    }
-    /// Returns true if the maximum block time rule is active for `network` and `height`.
-    ///
-    /// Always returns true if `network` is the Mainnet.
-    /// If `network` is the Testnet, the `height` should be at least
-    /// TESTNET_MAX_TIME_START_HEIGHT to return true.
-    /// Returns false otherwise.
-    ///
-    /// Part of the consensus rules at <https://zips.z.cash/protocol/protocol.pdf#blockheader>
-    pub fn is_max_block_time_enforced(&self, height: block::Height) -> bool {
+    pub fn b58_script_address_prefix(self) -> [u8; 2] {
         match self {
-            Network::Mainnet => true,
-            Network::Testnet => height >= super::TESTNET_MAX_TIME_START_HEIGHT,
+            Self::Mainnet => constants::mainnet::B58_SCRIPT_ADDRESS_PREFIX,
+            Self::Testnet | Self::Regtest => constants::testnet::B58_SCRIPT_ADDRESS_PREFIX,
+        }
+    }
+
+    /// Return the network name as defined in
+    /// [BIP70](https://github.com/bitcoin/bips/blob/master/bip-0070.mediawiki#paymentdetailspaymentrequest)
+    pub fn bip70_network_name(&self) -> String {
+        if *self == Self::Mainnet {
+            "main".to_string()
+        } else {
+            "test".to_string()
+        }
+    }
+}
+
+impl From<NetworkKind> for &'static str {
+    fn from(network: NetworkKind) -> &'static str {
+        // These should be different from the `Display` impl for `Network` so that its lowercase form
+        // can't be parsed as the default Testnet in the `Network` `FromStr` impl, it's easy to
+        // distinguish them in logs, and so it's generally harder to confuse the two.
+        match network {
+            NetworkKind::Mainnet => "MainnetKind",
+            NetworkKind::Testnet => "TestnetKind",
+            NetworkKind::Regtest => "RegtestKind",
         }
     }
 }
 
+impl fmt::Display for NetworkKind {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.write_str((*self).into())
+    }
+}
+
 impl From<&Network> for &'static str {
     fn from(network: &Network) -> &'static str {
         match network {
             Network::Mainnet => "Mainnet",
-            Network::Testnet => "Testnet",
+            // TODO:
+            // - Add a `name` field to use here instead of checking `is_default_testnet()`
+            // - zcashd calls the Regtest cache dir 'regtest' (#8327).
+            Network::Testnet(params) if params.is_default_testnet() => "Testnet",
+            Network::Testnet(_params) => "UnknownTestnet",
         }
     }
 }
@@ -108,17 +162,62 @@ impl fmt::Display for Network {
 }
 
 impl Network {
+    /// Creates a new [`Network::Testnet`] with the default Testnet [`testnet::Parameters`].
+    pub fn new_default_testnet() -> Self {
+        Self::Testnet(Arc::new(testnet::Parameters::default()))
+    }
+
+    /// Creates a new configured [`Network::Testnet`] with the provided Testnet [`testnet::Parameters`].
+    pub fn new_configured_testnet(params: testnet::Parameters) -> Self {
+        Self::Testnet(Arc::new(params))
+    }
+
+    /// Returns true if the network is the default Testnet, or false otherwise.
+    pub fn is_default_testnet(&self) -> bool {
+        if let Self::Testnet(params) = self {
+            params.is_default_testnet()
+        } else {
+            false
+        }
+    }
+
+    /// Returns the [`NetworkKind`] for this network.
+    pub fn kind(&self) -> NetworkKind {
+        match self {
+            Network::Mainnet => NetworkKind::Mainnet,
+            // TODO: Return `NetworkKind::Regtest` if the parameters match the default Regtest params
+            Network::Testnet(_) => NetworkKind::Testnet,
+        }
+    }
+
     /// Returns an iterator over [`Network`] variants.
     pub fn iter() -> impl Iterator<Item = Self> {
         // TODO: Use default values of `Testnet` variant when adding fields for #7845.
-        [Self::Mainnet, Self::Testnet].into_iter()
+        [Self::Mainnet, Self::new_default_testnet()].into_iter()
+    }
+
+    /// Returns true if the maximum block time rule is active for `network` and `height`.
+    ///
+    /// Always returns true if `network` is the Mainnet.
+    /// If `network` is the Testnet, the `height` should be at least
+    /// TESTNET_MAX_TIME_START_HEIGHT to return true.
+    /// Returns false otherwise.
+    ///
+    /// Part of the consensus rules at <https://zips.z.cash/protocol/protocol.pdf#blockheader>
+    pub fn is_max_block_time_enforced(&self, height: block::Height) -> bool {
+        match self {
+            Network::Mainnet => true,
+            // TODO: Move `TESTNET_MAX_TIME_START_HEIGHT` to a field on testnet::Parameters (#8364)
+            Network::Testnet(_params) => height >= super::TESTNET_MAX_TIME_START_HEIGHT,
+        }
     }
 
     /// Get the default port associated to this network.
     pub fn default_port(&self) -> u16 {
         match self {
             Network::Mainnet => 8233,
-            Network::Testnet => 18233,
+            // TODO: Add a `default_port` field to `testnet::Parameters` to return here. (zcashd uses 18344 for Regtest)
+            Network::Testnet(_params) => 18233,
         }
     }
 
@@ -143,10 +242,7 @@ impl Network {
     /// Return the network name as defined in
     /// [BIP70](https://github.com/bitcoin/bips/blob/master/bip-0070.mediawiki#paymentdetailspaymentrequest)
     pub fn bip70_network_name(&self) -> String {
-        match self {
-            Network::Mainnet => "main".to_string(),
-            Network::Testnet => "test".to_string(),
-        }
+        self.kind().bip70_network_name()
     }
 
     /// Return the lowercase network name.
@@ -167,13 +263,14 @@ impl Network {
     }
 }
 
+// This is used for parsing a command-line argument for the `TipHeight` command in zebrad.
 impl FromStr for Network {
     type Err = InvalidNetworkError;
 
     fn from_str(string: &str) -> Result<Self, Self::Err> {
         match string.to_lowercase().as_str() {
             "mainnet" => Ok(Network::Mainnet),
-            "testnet" => Ok(Network::Testnet),
+            "testnet" => Ok(Network::new_default_testnet()),
             _ => Err(InvalidNetworkError(string.to_owned())),
         }
     }

zebra-chain/src/parameters/network/testnet.rs

@@ -0,0 +1,16 @@
+//! Types and implementation for Testnet consensus parameters
+
+#[cfg(any(test, feature = "proptest-impl"))]
+use proptest_derive::Arbitrary;
+
+/// Network consensus parameters for test networks such as Regtest and the default Testnet.
+#[derive(Clone, Debug, Default, Eq, PartialEq, Hash, Serialize, Deserialize)]
+#[cfg_attr(any(test, feature = "proptest-impl"), derive(Arbitrary))]
+pub struct Parameters {}
+
+impl Parameters {
+    /// Returns true if the instance of [`Parameters`] represents the default public Testnet.
+    pub fn is_default_testnet(&self) -> bool {
+        self == &Self::default()
+    }
+}

zebra-chain/src/parameters/network/tests/prop.rs

@@ -34,6 +34,6 @@ proptest! {
         let _init_guard = zebra_test::init();
 
         assert!(Network::Mainnet.is_max_block_time_enforced(height));
-        assert_eq!(Network::Testnet.is_max_block_time_enforced(height), TESTNET_MAX_TIME_START_HEIGHT <= height);
+        assert_eq!(Network::new_default_testnet().is_max_block_time_enforced(height), TESTNET_MAX_TIME_START_HEIGHT <= height);
     }
 }

zebra-chain/src/parameters/network_upgrade.rs

@@ -271,7 +271,8 @@ impl Network {
         };
         match self {
             Mainnet => mainnet_heights,
-            Testnet => testnet_heights,
+            // TODO: Add an `activation_heights` field to `testnet::Parameters` to return here. (#7970)
+            Testnet(_params) => testnet_heights,
         }
         .iter()
         .cloned()
@@ -394,9 +395,14 @@ impl NetworkUpgrade {
         height: block::Height,
     ) -> Option<Duration> {
         match (network, height) {
-            (Network::Testnet, height) if height < TESTNET_MINIMUM_DIFFICULTY_START_HEIGHT => None,
+            // TODO: Move `TESTNET_MINIMUM_DIFFICULTY_START_HEIGHT` to a field on testnet::Parameters (#8364)
+            (Network::Testnet(_params), height)
+                if height < TESTNET_MINIMUM_DIFFICULTY_START_HEIGHT =>
+            {
+                None
+            }
             (Network::Mainnet, _) => None,
-            (Network::Testnet, _) => {
+            (Network::Testnet(_params), _) => {
                 let network_upgrade = NetworkUpgrade::current(network, height);
                 Some(network_upgrade.target_spacing() * TESTNET_MINIMUM_DIFFICULTY_GAP_MULTIPLIER)
             }

zebra-chain/src/parameters/tests.rs

@@ -21,7 +21,7 @@ fn activation_bijective() {
     let mainnet_nus: HashSet<&NetworkUpgrade> = mainnet_activations.values().collect();
     assert_eq!(MAINNET_ACTIVATION_HEIGHTS.len(), mainnet_nus.len());
 
-    let testnet_activations = Testnet.activation_list();
+    let testnet_activations = Network::new_default_testnet().activation_list();
     let testnet_heights: HashSet<&block::Height> = testnet_activations.keys().collect();
     assert_eq!(TESTNET_ACTIVATION_HEIGHTS.len(), testnet_heights.len());
 
@@ -38,7 +38,7 @@ fn activation_extremes_mainnet() {
 #[test]
 fn activation_extremes_testnet() {
     let _init_guard = zebra_test::init();
-    activation_extremes(Testnet)
+    activation_extremes(Network::new_default_testnet())
 }
 
 /// Test the activation_list, activation_height, current, and next functions
@@ -115,7 +115,7 @@ fn activation_consistent_mainnet() {
 #[test]
 fn activation_consistent_testnet() {
     let _init_guard = zebra_test::init();
-    activation_consistent(Testnet)
+    activation_consistent(Network::new_default_testnet())
 }
 
 /// Check that the `activation_height`, `is_activation_height`,
@@ -178,7 +178,7 @@ fn branch_id_extremes_mainnet() {
 #[test]
 fn branch_id_extremes_testnet() {
     let _init_guard = zebra_test::init();
-    branch_id_extremes(Testnet)
+    branch_id_extremes(Network::new_default_testnet())
 }
 
 /// Test the branch_id_list, branch_id, and current functions for `network` with
@@ -217,7 +217,7 @@ fn branch_id_consistent_mainnet() {
 #[test]
 fn branch_id_consistent_testnet() {
     let _init_guard = zebra_test::init();
-    branch_id_consistent(Testnet)
+    branch_id_consistent(Network::new_default_testnet())
 }
 
 /// Check that the branch_id and current functions are consistent for `network`.