[move-cm][closures] Refactor: Move type conversions out of Loader i…

…nto a trait

Type conversions from runtime types to `MoveTypeLayout` and `TypeTag` currently are associated with the `Loader` type. However, they are needed for the `FunctionValueExtension` trait which needs to be constructed in contexts where no loader but only `ModuleStorage` exists.

This PR moves the conversion functions into a new trait `TypeConverter`. The trait is then implemented two times based on `ModuleStorage` only and based on the existing `Loader`, for downwards compatibility.

third_party/move/move-core/types/src/value.rs

@@ -9,8 +9,9 @@
 
 use crate::{
     account_address::AccountAddress,
-    identifier::Identifier,
-    language_storage::{StructTag, TypeTag},
+    ident_str,
+    identifier::{IdentStr, Identifier},
+    language_storage::{ModuleId, StructTag, TypeTag},
     u256,
 };
 use anyhow::{anyhow, bail, Result as AResult};
@@ -182,6 +183,30 @@ pub enum IdentifierMappingKind {
     DerivedString,
 }
 
+impl IdentifierMappingKind {
+    /// If the struct identifier has a special mapping, return it.
+    pub fn from_ident(
+        module_id: &ModuleId,
+        struct_id: &Identifier,
+    ) -> Option<IdentifierMappingKind> {
+        let ident_str_to_kind = |ident_str: &IdentStr| -> Option<IdentifierMappingKind> {
+            if ident_str.eq(ident_str!("Aggregator")) {
+                Some(IdentifierMappingKind::Aggregator)
+            } else if ident_str.eq(ident_str!("AggregatorSnapshot")) {
+                Some(IdentifierMappingKind::Snapshot)
+            } else if ident_str.eq(ident_str!("DerivedStringSnapshot")) {
+                Some(IdentifierMappingKind::DerivedString)
+            } else {
+                None
+            }
+        };
+        (module_id.address().eq(&AccountAddress::ONE)
+            && module_id.name().eq(ident_str!("aggregator_v2")))
+        .then(|| ident_str_to_kind(struct_id.as_ident_str()))
+        .flatten()
+    }
+}
+
 #[derive(Debug, Clone, Hash, Serialize, Deserialize, PartialEq, Eq)]
 #[cfg_attr(
     any(test, feature = "fuzzing"),
@@ -822,7 +847,7 @@ impl fmt::Display for MoveTypeLayout {
             U256 => write!(f, "u256"),
             Address => write!(f, "address"),
             Vector(typ) => write!(f, "vector<{}>", typ),
-            Struct(s) => write!(f, "{}", s),
+            Struct(s) => fmt::Display::fmt(s, f),
             Signer => write!(f, "signer"),
             // TODO[agg_v2](cleanup): consider printing the tag as well.
             Native(_, typ) => write!(f, "native<{}>", typ),

third_party/move/move-vm/runtime/src/lib.rs

@@ -48,4 +48,5 @@ pub use storage::{
     },
     module_storage::{ambassador_impl_ModuleStorage, AsFunctionValueExtension, ModuleStorage},
     publishing::{StagingModuleStorage, VerifiedModuleBundle},
+    type_converter::{ModuleStorageTypeConverter, TypeConverter},
 };