feat(applying): scaffold Shelley phase-1 validations

pallas-applying/src/lib.rs

@@ -1,11 +1,14 @@
 //! Logic for validating and applying new blocks and txs to the chain state
 
 pub mod byron;
+pub mod shelley;
 pub mod types;
 
 use byron::validate_byron_tx;
-
-use pallas_traverse::{MultiEraTx, MultiEraTx::Byron as ByronTxPayload};
+use pallas_traverse::{
+    Era, MultiEraTx, MultiEraTx::AlonzoCompatible, MultiEraTx::Byron as ByronTxPayload,
+};
+use shelley::validate_shelley_tx;
 
 pub use types::{Environment, MultiEraProtParams, UTxOs, ValidationResult};
 
@@ -18,6 +21,13 @@ pub fn validate(metx: &MultiEraTx, utxos: &UTxOs, env: &Environment) -> Validati
                 prot_magic,
             },
         ) => validate_byron_tx(mtxp, utxos, bpp, prot_magic),
+        (
+            AlonzoCompatible(shelley_minted_tx, Era::Shelley),
+            Environment {
+                prot_params: MultiEraProtParams::Shelley(spp),
+                prot_magic,
+            },
+        ) => validate_shelley_tx(shelley_minted_tx, utxos, spp, prot_magic),
         // TODO: implement the rest of the eras.
         _ => Ok(()),
     }

pallas-applying/src/shelley.rs

@@ -0,0 +1,15 @@
+//! Utilities required for Shelley-era transaction validation.
+
+use crate::types::{ShelleyProtParams, UTxOs, ValidationResult};
+
+use pallas_primitives::alonzo::MintedTx;
+
+// TODO: implement each of the validation rules.
+pub fn validate_shelley_tx(
+    _mtxp: &MintedTx,
+    _utxos: &UTxOs,
+    _prot_pps: &ShelleyProtParams,
+    _prot_magic: &u32,
+) -> ValidationResult {
+    Ok(())
+}

pallas-applying/src/types.rs

@@ -13,11 +13,15 @@ pub struct ByronProtParams {
     pub max_tx_size: u64,
 }
 
+#[derive(Debug, Clone)]
+pub struct ShelleyProtParams;
+
 // TODO: add variants for the other eras.
 #[derive(Debug)]
 #[non_exhaustive]
 pub enum MultiEraProtParams {
     Byron(ByronProtParams),
+    Shelley(ShelleyProtParams),
 }
 
 #[derive(Debug)]