From da2490f1431abebf4bf851ef6e6581645272269c Mon Sep 17 00:00:00 2001
From: Stan Bondi <sdbondi@users.noreply.github.com>
Date: Tue, 24 Dec 2024 09:04:59 +0200
Subject: [PATCH] fix(template): add full typename to invalid argument error

---
 dan_layer/engine/tests/test.rs                |  3 ++-
 dan_layer/template_abi/src/rust.rs            | 22 +++++++++++++++++--
 .../template_lib/src/template_dependencies.rs |  2 +-
 .../src/template/dispatcher.rs                |  2 +-
 4 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/dan_layer/engine/tests/test.rs b/dan_layer/engine/tests/test.rs
index 0c2bfdffd..3a24c0515 100644
--- a/dan_layer/engine/tests/test.rs
+++ b/dan_layer/engine/tests/test.rs
@@ -384,7 +384,8 @@ mod errors {
         match result.finalize.result.full_reject().unwrap() {
             RejectReason::ExecutionFailure(message) => {
                 assert!(message.starts_with(
-                    "Panic! failed to decode argument at position 0 for function 'please_pass_invalid_args':"
+                    "Panic! failed to decode argument at position 0 (tari_template_lib::models::amount::Amount) for \
+                     function 'please_pass_invalid_args':"
                 ),);
             },
             reason => panic!("Unexpected failure reason: {}", reason),
diff --git a/dan_layer/template_abi/src/rust.rs b/dan_layer/template_abi/src/rust.rs
index 50c914225..f6a865c52 100644
--- a/dan_layer/template_abi/src/rust.rs
+++ b/dan_layer/template_abi/src/rust.rs
@@ -25,7 +25,7 @@ mod no_std {
     extern crate alloc;
 
     pub use alloc::{boxed, format, str, string, vec};
-    pub use core::{cmp, fmt, iter, mem, num, ops, ptr, slice, write, writeln};
+    pub use core::{any, cmp, fmt, iter, mem, num, ops, ptr, slice, write, writeln};
 
     pub mod collections {
         extern crate alloc;
@@ -41,7 +41,25 @@ pub use no_std::*;
 
 #[cfg(feature = "std")]
 mod rust_std {
-    pub use ::std::{boxed, cmp, fmt, format, io, iter, mem, num, ops, ptr, slice, str, string, vec, write, writeln};
+    pub use ::std::{
+        any,
+        boxed,
+        cmp,
+        fmt,
+        format,
+        io,
+        iter,
+        mem,
+        num,
+        ops,
+        ptr,
+        slice,
+        str,
+        string,
+        vec,
+        write,
+        writeln,
+    };
 
     pub mod collections {
         pub use ::std::collections::{BTreeMap, BTreeSet, HashMap, HashSet};
diff --git a/dan_layer/template_lib/src/template_dependencies.rs b/dan_layer/template_lib/src/template_dependencies.rs
index bc0500686..55ac4eae0 100644
--- a/dan_layer/template_lib/src/template_dependencies.rs
+++ b/dan_layer/template_lib/src/template_dependencies.rs
@@ -23,6 +23,6 @@
 //! Public types that are available to internal template code.
 
 pub use tari_bor::{decode, decode_exact, encode_with_len, from_value, serde};
-pub use tari_template_abi::{wrap_ptr, CallInfo};
+pub use tari_template_abi::{rust, wrap_ptr, CallInfo};
 
 pub use crate::{args::LogLevel, debug, engine, get_context as context, init_context, panic_hook::register_panic_hook};
diff --git a/dan_layer/template_macros/src/template/dispatcher.rs b/dan_layer/template_macros/src/template/dispatcher.rs
index ee4b70a40..cbaaee98e 100644
--- a/dan_layer/template_macros/src/template/dispatcher.rs
+++ b/dan_layer/template_macros/src/template/dispatcher.rs
@@ -128,7 +128,7 @@ fn get_function_block(template_ident: &Ident, ast: FunctionAst) -> Expr {
                 args.push(parse_quote! { #arg_ident });
                 stmts.push(parse_quote! {
                     let #arg_ident = from_value::<#type_path>(&call_info.args[#i])
-                        .unwrap_or_else(|e| panic!("failed to decode argument at position {} for function '{}': {}", #i, #func_name, e));
+                        .unwrap_or_else(|e| panic!("failed to decode argument at position {} ({}) for function '{}': {}", #i, rust::any::type_name::<#type_path>(), #func_name, e));
                 })
             },
             TypeAst::Tuple { type_tuple, .. } => {