Fix the code to support compilation with tx-v6 feature flag disabled, make this flag non-default in Cargo.toml files and enable it by default in .cargo/config.toml

Author: dmidem

.cargo/config.toml

@@ -3,6 +3,9 @@
 # Flags that apply to all Zebra crates and configurations
 [target.'cfg(all())']
 rustflags = [
+    # Enable tx-v6 everywhere by default
+    "--cfg", 'feature="tx-v6"',
+
     # TODO: Consider removing this line later (it's needed for the ZSA version of librustzcash crates)
     "--cfg", "zcash_unstable=\"nu6\"",
 
@@ -85,6 +88,9 @@ rustflags = [
 
 [build]
 rustdocflags = [
+    # Enable tx-v6 everywhere by default
+    "--cfg", 'feature="tx-v6"',
+
     # TODO: Consider removing this line later (it's needed for the ZSA version of librustzcash crates)
     "--cfg", "zcash_unstable=\"nu6\"",
 

zebra-chain/Cargo.toml

@@ -15,8 +15,7 @@ keywords = ["zebra", "zcash"]
 categories = ["asynchronous", "cryptography::cryptocurrencies", "encoding"]
 
 [features]
-#default = []
-default = ["tx-v6"]
+default = []
 
 # Production features that activate extra functionality
 

zebra-chain/src/orchard/note/ciphertexts.rs

@@ -109,10 +109,13 @@ impl ZcashDeserialize for WrappedNoteKey {
 #[cfg(test)]
 mod tests {
     use crate::{
-        orchard::{OrchardVanilla, OrchardZSA, ShieldedDataFlavor, WrappedNoteKey},
+        orchard::{OrchardVanilla, ShieldedDataFlavor, WrappedNoteKey},
         serialization::{ZcashDeserialize, ZcashSerialize},
     };
 
+    #[cfg(feature = "tx-v6")]
+    use crate::orchard::OrchardZSA;
+
     use proptest::prelude::*;
 
     fn roundtrip_encrypted_note<EncryptedNote>(note: &EncryptedNote) -> EncryptedNote
@@ -135,6 +138,7 @@ mod tests {
         }
 
 
+        #[cfg(feature = "tx-v6")]
         #[test]
         fn encrypted_ciphertext_roundtrip_orchard_zsa(ec in any::<<OrchardZSA as ShieldedDataFlavor>::EncryptedNote>()) {
             let _init_guard = zebra_test::init();

zebra-chain/src/orchard/shielded_data.rs

@@ -27,10 +27,17 @@ use super::{OrchardVanilla, ShieldedDataFlavor};
 
 /// A bundle of [`Action`] descriptions and signature data.
 #[derive(Clone, Debug, PartialEq, Eq, Deserialize, Serialize)]
-#[serde(bound(
-    serialize = "Flavor::EncryptedNote: serde::Serialize, Flavor::BurnType: serde::Serialize",
-    deserialize = "Flavor::BurnType: serde::Deserialize<'de>"
-))]
+#[cfg_attr(
+    not(feature = "tx-v6"),
+    serde(bound(serialize = "Flavor::EncryptedNote: serde::Serialize"))
+)]
+#[cfg_attr(
+    feature = "tx-v6",
+    serde(bound(
+        serialize = "Flavor::EncryptedNote: serde::Serialize, Flavor::BurnType: serde::Serialize",
+        deserialize = "Flavor::BurnType: serde::Deserialize<'de>"
+    ))
+)]
 pub struct ShieldedData<Flavor: ShieldedDataFlavor> {
     /// The orchard flags for this transaction.
     /// Denoted as `flagsOrchard` in the spec.

zebra-chain/src/orchard/shielded_data_flavor.rs

@@ -9,16 +9,16 @@ use orchard::{domain::OrchardDomainCommon, orchard_flavor::OrchardFlavor};
 pub use orchard::orchard_flavor::OrchardVanilla;
 
 #[cfg(feature = "tx-v6")]
-pub use orchard::orchard_flavor::OrchardZSA;
+pub use orchard::{note::AssetBase, orchard_flavor::OrchardZSA, value::NoteValue};
 
+use crate::serialization::{ZcashDeserialize, ZcashSerialize};
+
+#[cfg(feature = "tx-v6")]
 use crate::{
     orchard::ValueCommitment,
-    serialization::{ZcashDeserialize, ZcashSerialize},
+    orchard_zsa::{Burn, BurnItem, NoBurn},
 };
 
-#[cfg(feature = "tx-v6")]
-use crate::orchard_zsa::{Burn, BurnItem, NoBurn};
-
 use super::note;
 
 // When testing or with the proptest-impl feature, enforce Arbitrary.
@@ -62,6 +62,7 @@ pub trait ShieldedDataFlavor: OrchardFlavor {
         + ZcashSerialize
         + Into<ValueCommitment>
         + AsRef<[BurnItem]>
+        + for<'a> From<&'a [(AssetBase, NoteValue)]>
         + test_arbitrary::TestArbitrary;
 }
 

zebra-chain/src/transaction.rs

@@ -40,7 +40,7 @@ pub use unmined::{
 
 use crate::{
     amount::{Amount, Error as AmountError, NegativeAllowed, NonNegative},
-    block, orchard, orchard_zsa,
+    block, orchard,
     parameters::{ConsensusBranchId, NetworkUpgrade},
     primitives::{ed25519, Bctv14Proof, Groth16Proof},
     sapling,
@@ -53,6 +53,9 @@ use crate::{
     value_balance::{ValueBalance, ValueBalanceError},
 };
 
+#[cfg(feature = "tx-v6")]
+use crate::orchard_zsa;
+
 /// A Zcash transaction.
 ///
 /// A transaction is an encoded data structure that facilitates the transfer of

zebra-chain/src/transaction/arbitrary.rs

@@ -880,13 +880,25 @@ impl Arbitrary for Transaction {
                 Self::v5_strategy(ledger_state)
             ]
             .boxed(),
-            #[cfg(feature = "tx-v6")]
-            NetworkUpgrade::Nu7 => prop_oneof![
-                Self::v4_strategy(ledger_state.clone()),
-                Self::v5_strategy(ledger_state.clone()),
-                Self::v6_strategy(ledger_state)
-            ]
-            .boxed(),
+            NetworkUpgrade::Nu7 => {
+                #[cfg(not(feature = "tx-v6"))]
+                {
+                    prop_oneof![
+                        Self::v4_strategy(ledger_state.clone()),
+                        Self::v5_strategy(ledger_state.clone()),
+                    ]
+                    .boxed()
+                }
+                #[cfg(feature = "tx-v6")]
+                {
+                    prop_oneof![
+                        Self::v4_strategy(ledger_state.clone()),
+                        Self::v5_strategy(ledger_state.clone()),
+                        Self::v6_strategy(ledger_state),
+                    ]
+                    .boxed()
+                }
+            }
         }
     }
 

zebra-chain/src/transaction/serialize.rs

@@ -10,20 +10,21 @@ use reddsa::{orchard::Binding, orchard::SpendAuth, Signature};
 
 use crate::{
     block::MAX_BLOCK_BYTES,
-    orchard::{OrchardVanilla, OrchardZSA, ShieldedDataFlavor},
-    orchard_zsa::NoBurn,
+    orchard::{OrchardVanilla, ShieldedDataFlavor},
     parameters::{OVERWINTER_VERSION_GROUP_ID, SAPLING_VERSION_GROUP_ID, TX_V5_VERSION_GROUP_ID},
     primitives::{Halo2Proof, ZkSnarkProof},
     serialization::{
         zcash_deserialize_external_count, zcash_serialize_empty_list,
-        zcash_serialize_external_count, AtLeastOne, CompactSizeMessage, ReadZcashExt,
-        SerializationError, TrustedPreallocate, ZcashDeserialize, ZcashDeserializeInto,
-        ZcashSerialize,
+        zcash_serialize_external_count, AtLeastOne, ReadZcashExt, SerializationError,
+        TrustedPreallocate, ZcashDeserialize, ZcashDeserializeInto, ZcashSerialize,
     },
 };
 
 #[cfg(feature = "tx-v6")]
-use crate::parameters::TX_V6_VERSION_GROUP_ID;
+use crate::{
+    orchard::OrchardZSA, orchard_zsa::NoBurn, parameters::TX_V6_VERSION_GROUP_ID,
+    serialization::CompactSizeMessage,
+};
 
 use super::*;
 use crate::sapling;
@@ -503,6 +504,7 @@ impl ZcashDeserialize for Option<orchard::ShieldedData<OrchardVanilla>> {
         Ok(Some(orchard::ShieldedData::<OrchardVanilla> {
             flags,
             value_balance,
+            #[cfg(feature = "tx-v6")]
             burn: NoBurn,
             shared_anchor,
             proof,

zebra-consensus/Cargo.toml

@@ -15,8 +15,7 @@ keywords = ["zebra", "zcash"]
 categories = ["asynchronous", "cryptography::cryptocurrencies"]
 
 [features]
-#default = []
-default = ["tx-v6"]
+default = []
 
 # Production features that activate extra dependencies, or extra features in dependencies
 

zebra-consensus/src/primitives/halo2.rs

@@ -19,7 +19,10 @@ use tower::{util::ServiceFn, Service};
 use tower_batch_control::{Batch, BatchControl};
 use tower_fallback::Fallback;
 
-use zebra_chain::orchard::{OrchardVanilla, OrchardZSA, ShieldedData, ShieldedDataFlavor};
+use zebra_chain::orchard::{OrchardVanilla, ShieldedData, ShieldedDataFlavor};
+
+#[cfg(feature = "tx-v6")]
+use zebra_chain::orchard::OrchardZSA;
 
 use crate::BoxError;
 
@@ -78,7 +81,10 @@ pub type ItemVerifyingKey = VerifyingKey;
 lazy_static::lazy_static! {
     /// The halo2 proof verifying key for Orchard Vanilla
     pub static ref VERIFYING_KEY_VANILLA: ItemVerifyingKey = ItemVerifyingKey::build::<OrchardVanilla>();
+}
 
+#[cfg(feature = "tx-v6")]
+lazy_static::lazy_static! {
     /// The halo2 proof verifying key for OrchardZSA
     pub static ref VERIFYING_KEY_ZSA: ItemVerifyingKey = ItemVerifyingKey::build::<OrchardZSA>();
 }
@@ -241,6 +247,7 @@ pub static VERIFIER_VANILLA: Lazy<VerificationContext> =
     Lazy::new(create_verification_context::<OrchardVanilla>);
 
 /// FIXME: copy a doc from VERIFIER_VANILLA or just refer to its doc?
+#[cfg(feature = "tx-v6")]
 pub static VERIFIER_ZSA: Lazy<VerificationContext> =
     Lazy::new(create_verification_context::<OrchardZSA>);
 
@@ -256,6 +263,7 @@ impl OrchardVerifier for OrchardVanilla {
     }
 }
 
+#[cfg(feature = "tx-v6")]
 impl OrchardVerifier for OrchardZSA {
     const ZSA_ENABLED: bool = true;