feat: add a new subcommand for tx simulation

crates/cli/Cargo.toml

@@ -13,4 +13,7 @@ authors = ["Lucas Rosa <x@rvcas.dev>", "Kasey White <kwhitemsg@gmail.com>"]
 [dependencies]
 anyhow = "1.0.57"
 clap = { version = "3.1.14", features = ["derive"] }
+hex = "0.4.3"
+pallas-primitives = "0.13.2"
+pallas-traverse = "0.13.2"
 uplc = { path = '../uplc', version = "0.0.12" }

crates/cli/src/args.rs

@@ -7,11 +7,25 @@ use clap::{Parser, Subcommand};
 #[clap(version, about, long_about = None)]
 #[clap(propagate_version = true)]
 pub enum Args {
+    /// A subcommand for working with transactions
+    #[clap(subcommand)]
+    Tx(TxCommand),
     /// A subcommand for working with Untyped Plutus Core
     #[clap(subcommand)]
     Uplc(UplcCommand),
 }
 
+/// Commands for working with transactions
+#[derive(Subcommand)]
+pub enum TxCommand {
+    /// Simulate a transaction by evaluating it's script
+    Simulate {
+        input: PathBuf,
+        #[clap(short, long)]
+        cbor: bool,
+    },
+}
+
 /// Commands for working with Untyped Plutus Core
 #[derive(Subcommand)]
 pub enum UplcCommand {

crates/cli/src/main.rs

@@ -1,5 +1,6 @@
 use std::{fmt::Write as _, fs};
 
+use pallas_traverse::{Era, MultiEraTx};
 use uplc::{
     ast::{DeBruijn, FakeNamedDeBruijn, Name, NamedDeBruijn, Program, Term},
     machine::cost_model::ExBudget,
@@ -8,13 +9,29 @@ use uplc::{
 
 mod args;
 
-use args::{Args, UplcCommand};
+use args::{Args, TxCommand, UplcCommand};
 
 fn main() -> anyhow::Result<()> {
     let args = Args::default();
 
     match args {
-        Args::Uplc(uplc) => match uplc {
+        Args::Tx(tx_cmd) => match tx_cmd {
+            TxCommand::Simulate { input, cbor } => {
+                let tx_bytes = if cbor {
+                    fs::read(input)?
+                } else {
+                    let cbor_hex = fs::read_to_string(input)?;
+
+                    hex::decode(cbor_hex)?
+                };
+
+                let tx = MultiEraTx::decode(Era::Alonzo, &tx_bytes)
+                    .or_else(|_| MultiEraTx::decode(Era::Byron, &tx_bytes))?;
+
+                println!("{:?}", tx);
+            }
+        },
+        Args::Uplc(uplc_cmd) => match uplc_cmd {
             UplcCommand::Flat { input, print, out } => {
                 let code = std::fs::read_to_string(&input)?;