feat: add ability to downcast void to data

crates/aiken-lang/src/builder.rs

@@ -4,7 +4,7 @@ use indexmap::{IndexMap, IndexSet};
 use itertools::Itertools;
 use uplc::{
     ast::{
-        builder::{apply_wrap, delayed_choose_list, if_else},
+        builder::{apply_wrap, delayed_choose_list, delayed_if_else, if_else},
         Constant as UplcConstant, Name, Term, Type as UplcType,
     },
     builtins::DefaultFunction,
@@ -190,6 +190,18 @@ pub fn convert_type_to_data(term: Term<Name>, field_type: &Arc<Type>) -> Term<Na
         apply_wrap(DefaultFunction::BData.into(), term)
     } else if field_type.is_int() {
         apply_wrap(DefaultFunction::IData.into(), term)
+    } else if field_type.is_void() {
+        apply_wrap(
+            apply_wrap(Term::Builtin(DefaultFunction::ChooseUnit).force_wrap(), term),
+            Term::Constant(
+                UplcConstant::Data(PlutusData::Constr(Constr {
+                    tag: convert_constr_to_tag(0).unwrap(),
+                    any_constructor: None,
+                    fields: vec![],
+                }))
+                .into(),
+            ),
+        )
     } else if field_type.is_map() {
         apply_wrap(DefaultFunction::MapData.into(), term)
     } else if field_type.is_string() {
@@ -279,6 +291,23 @@ pub fn convert_data_to_type(term: Term<Name>, field_type: &Arc<Type>) -> Term<Na
         apply_wrap(DefaultFunction::UnIData.into(), term)
     } else if field_type.is_bytearray() {
         apply_wrap(DefaultFunction::UnBData.into(), term)
+    } else if field_type.is_void() {
+        delayed_if_else(
+            apply_wrap(
+                apply_wrap(
+                    DefaultFunction::EqualsInteger.into(),
+                    Term::Constant(UplcConstant::Integer(0.into()).into()),
+                ),
+                apply_wrap(
+                    Term::Builtin(DefaultFunction::FstPair)
+                        .force_wrap()
+                        .force_wrap(),
+                    apply_wrap(DefaultFunction::UnConstrData.into(), term),
+                ),
+            ),
+            Term::Constant(UplcConstant::Unit.into()),
+            Term::Error,
+        )
     } else if field_type.is_map() {
         apply_wrap(DefaultFunction::UnMapData.into(), term)
     } else if field_type.is_string() {
@@ -1289,7 +1318,11 @@ pub fn convert_constants_to_data(constants: Vec<Rc<UplcConstant>>) -> Vec<UplcCo
                 )])))
             }
             d @ UplcConstant::Data(_) => d.clone(),
-            _ => unreachable!(),
+            UplcConstant::Unit => UplcConstant::Data(PlutusData::Constr(Constr {
+                tag: convert_constr_to_tag(0).unwrap(),
+                any_constructor: None,
+                fields: vec![],
+            })),
         };
         new_constants.push(constant);
     }

crates/aiken-lang/src/uplc.rs

@@ -253,15 +253,25 @@ impl<'a> CodeGenerator<'a> {
                                 count: args.len(),
                             });
 
-                            for arg in args {
+                            if let Some(fun_arg_types) = fun.tipo().arg_types() {
+                                for (arg, func_type) in args.iter().zip(fun_arg_types) {
                                     let mut scope = scope.clone();
                                     scope.push(self.id_gen.next());
+
+                                    if func_type.is_data() && !arg.value.tipo().is_data() {
+                                        ir_stack.push(Air::WrapData {
+                                            scope: scope.clone(),
+                                            tipo: arg.value.tipo(),
+                                        })
+                                    }
+
                                     self.build_ir(&arg.value, ir_stack, scope);
                                 }
                                 return;
                             }
                         }
                     }
+                }
 
                 ir_stack.push(Air::Call {
                     scope: scope.clone(),

examples/acceptance_tests/055/lib/tests.ak

@@ -1,7 +1,16 @@
 use aiken/bytearray
+use aiken/dict
 use aiken/hash.{Hash, Sha2_256, sha2_256}
+use aiken/interval.{Interval, IntervalBound, PositiveInfinity}
 use aiken/list
 use aiken/string
+use aiken/transaction.{
+  InlineDatum, Input, Output, OutputReference, Transaction, TransactionId,
+}
+use aiken/transaction/credential.{
+  Address, PublicKeyCredential, ScriptCredential, StakeCredential,
+}
+use aiken/transaction/value
 
 //  MerkleTree in Aiken (ported from: https://github.com/input-output-hk/hydra/blob/master/plutus-merkle-tree/src/Plutus/MerkleTree.hs)
 
@@ -64,3 +73,84 @@ test foo() {
   let mt = from_list(items)
   size(mt) == 3
 }
+
+// const keyhash = #"010203040506"
+
+// const scripthash = #"060504030201"
+
+// pub fn keyhash_address(with_stake_credential: Option<StakeCredential>) {
+//   Address {
+//     payment_credential: PublicKeyCredential(keyhash),
+//     stake_credential: with_stake_credential,
+//   }
+// }
+
+// pub fn scripthash_address(with_stake_credential: Option<StakeCredential>) {
+//   Address {
+//     payment_credential: ScriptCredential(scripthash),
+//     stake_credential: with_stake_credential,
+//   }
+// }
+
+// type SampleData {
+//   a: Int,
+//   b: ByteArray,
+// }
+
+// pub fn tx_1() -> Transaction {
+//   let sample_datum = SampleData { a: 1, b: #"01" }
+//   // let sample_data: Data = sample_datum
+//   let tx =
+//     Transaction {
+//       inputs: [
+//         Input {
+//           output_reference: OutputReference {
+//             transaction_id: TransactionId { hash: #"" },
+//             output_index: 0,
+//           },
+//           output: Output {
+//             address: scripthash_address(None),
+//             value: value.zero(),
+//             datum: InlineDatum(sample_datum),
+//             reference_script: None,
+//           },
+//         },
+//       ],
+//       reference_inputs: [],
+//       outputs: [
+//         Output {
+//           address: keyhash_address(None),
+//           value: value.from_lovelace(10000),
+//           datum: InlineDatum(sample_datum),
+//           reference_script: None,
+//         },
+//       ],
+//       fee: value.zero(),
+//       mint: value.from_asset(#"000000", #"00", -1),
+//       certificates: [],
+//       withdrawals: dict.new(),
+//       validity_range: Interval {
+//         lower_bound: IntervalBound {
+//           bound_type: PositiveInfinity,
+//           is_inclusive: True,
+//         },
+//         upper_bound: IntervalBound {
+//           bound_type: PositiveInfinity,
+//           is_inclusive: True,
+//         },
+//       },
+//       extra_signatories: [keyhash],
+//       redeemers: dict.new(),
+//       datums: dict.new(),
+//       id: TransactionId { hash: #"" },
+//     }
+//   tx
+// }
+
+// test some_test2() {
+//   tx_1() == tx_1()
+// }
+
+test some_test1() {
+  InlineDatum(Void) == InlineDatum(Void)
+}