Print type tags in Debug::print

language/move-stdlib/src/natives/debug.rs

@@ -6,6 +6,8 @@ use move_binary_format::errors::PartialVMResult;
 use move_core_types::gas_schedule::ONE_GAS_UNIT;
 use move_vm_runtime::native_functions::NativeContext;
 #[allow(unused_imports)]
+use move_vm_types::values::debug::print_reference_with_type;
+#[allow(unused_imports)]
 use move_vm_types::values::{values_impl::debug::print_reference, Reference};
 #[allow(unused_imports)]
 use move_vm_types::{
@@ -30,8 +32,9 @@ pub fn native_print(
         let ty = ty_args.pop().unwrap();
         let r = pop_arg!(args, Reference);
 
+        let type_tag = context.type_to_type_tag(&ty)?;
         let mut buf = String::new();
-        print_reference(&mut buf, &r)?;
+        print_reference_with_type(&mut buf, &type_tag, &r)?;
         println!("[debug] {}", buf);
     }
 

language/move-vm/types/src/values/values_impl.rs

@@ -2180,6 +2180,8 @@ impl Display for Locals {
 
 #[allow(dead_code)]
 pub mod debug {
+    use move_core_types::language_storage::TypeTag;
+
     use super::*;
     use std::fmt::Write;
 
@@ -2305,6 +2307,22 @@ pub mod debug {
         }
     }
 
+    /// Prints a [Reference] with the given [TypeTag].
+    pub fn print_reference_with_type<B: Write>(
+        buf: &mut B,
+        type_tag: &TypeTag,
+        r: &Reference,
+    ) -> PartialVMResult<()> {
+        write!(buf, "[{}] ", &type_tag).map_err(|_| {
+            PartialVMError::new(StatusCode::UNKNOWN_INVARIANT_VIOLATION_ERROR)
+                .with_message("debug print - could not print type tag".to_string())
+        })?;
+        match &r.0 {
+            ReferenceImpl::ContainerRef(r) => print_container_ref(buf, r),
+            ReferenceImpl::IndexedRef(r) => print_indexed_ref(buf, r),
+        }
+    }
+
     pub fn print_reference<B: Write>(buf: &mut B, r: &Reference) -> PartialVMResult<()> {
         match &r.0 {
             ReferenceImpl::ContainerRef(r) => print_container_ref(buf, r),