Update utils

utils/src/soroban_utils/mod.rs

@@ -2,11 +2,11 @@ extern crate rustc_lint;
 extern crate rustc_middle;
 extern crate rustc_span;
 
-use std::collections::HashSet;
-
+use crate::type_utils::match_type_to_str;
 use rustc_lint::LateContext;
-use rustc_middle::ty::{Ty, TyKind};
+use rustc_middle::ty::Ty;
 use rustc_span::def_id::DefId;
+use std::collections::HashSet;
 
 /// Constants defining the fully qualified names of Soroban types.
 const SOROBAN_ENV: &str = "soroban_sdk::Env";
@@ -58,28 +58,19 @@ pub fn is_soroban_function(
         .all(|pattern| checked_functions.contains(pattern))
 }
 
-// Private helper function to match soroban types
-fn is_soroban_type(cx: &LateContext<'_>, expr_type: Ty<'_>, type_str: &str) -> bool {
-    match expr_type.kind() {
-        TyKind::Adt(adt_def, _) => cx.tcx.def_path_str(adt_def.did()).contains(type_str),
-        TyKind::Ref(_, ty, _) => is_soroban_type(cx, *ty, type_str),
-        _ => false,
-    }
-}
-
 /// Checks if the provided type is a Soroban environment (`soroban_sdk::Env`).
 pub fn is_soroban_env(cx: &LateContext<'_>, expr_type: Ty<'_>) -> bool {
-    is_soroban_type(cx, expr_type, SOROBAN_ENV)
+    match_type_to_str(cx, expr_type, SOROBAN_ENV)
 }
 
 /// Checks if the provided type is a Soroban Address (`soroban_sdk::Address`).
 pub fn is_soroban_address(cx: &LateContext<'_>, expr_type: Ty<'_>) -> bool {
-    is_soroban_type(cx, expr_type, SOROBAN_ADDRESS)
+    match_type_to_str(cx, expr_type, SOROBAN_ADDRESS)
 }
 
 /// Checks if the provided type is a Soroban Map (`soroban_sdk::Map`).
 pub fn is_soroban_map(cx: &LateContext<'_>, expr_type: Ty<'_>) -> bool {
-    is_soroban_type(cx, expr_type, SOROBAN_MAP)
+    match_type_to_str(cx, expr_type, SOROBAN_MAP)
 }
 
 pub enum SorobanStorageType {
@@ -97,14 +88,16 @@ pub fn is_soroban_storage(
 ) -> bool {
     match storage_type {
         SorobanStorageType::Any => {
-            is_soroban_type(cx, expr_type, SOROBAN_INSTANCE_STORAGE)
-                || is_soroban_type(cx, expr_type, SOROBAN_TEMPORARY_STORAGE)
-                || is_soroban_type(cx, expr_type, SOROBAN_PERSISTENT_STORAGE)
+            match_type_to_str(cx, expr_type, SOROBAN_INSTANCE_STORAGE)
+                || match_type_to_str(cx, expr_type, SOROBAN_TEMPORARY_STORAGE)
+                || match_type_to_str(cx, expr_type, SOROBAN_PERSISTENT_STORAGE)
+        }
+        SorobanStorageType::Instance => match_type_to_str(cx, expr_type, SOROBAN_INSTANCE_STORAGE),
+        SorobanStorageType::Temporary => {
+            match_type_to_str(cx, expr_type, SOROBAN_TEMPORARY_STORAGE)
         }
-        SorobanStorageType::Instance => is_soroban_type(cx, expr_type, SOROBAN_INSTANCE_STORAGE),
-        SorobanStorageType::Temporary => is_soroban_type(cx, expr_type, SOROBAN_TEMPORARY_STORAGE),
         SorobanStorageType::Persistent => {
-            is_soroban_type(cx, expr_type, SOROBAN_PERSISTENT_STORAGE)
+            match_type_to_str(cx, expr_type, SOROBAN_PERSISTENT_STORAGE)
         }
     }
 }

utils/src/type_utils.rs

@@ -1,12 +1,35 @@
 extern crate rustc_hir;
 extern crate rustc_lint;
 extern crate rustc_middle;
+extern crate rustc_span;
 
-use rustc_hir::HirId;
+use rustc_hir::{FnDecl, FnRetTy, HirId, QPath};
 use rustc_lint::LateContext;
-use rustc_middle::ty::Ty;
+use rustc_middle::ty::{Ty, TyKind};
+use rustc_span::sym;
 
 /// Get the type of a node, if it exists.
 pub fn get_node_type_opt<'tcx>(cx: &LateContext<'tcx>, hir_id: &HirId) -> Option<Ty<'tcx>> {
     cx.typeck_results().node_type_opt(*hir_id)
 }
+
+/// Match the type of an expression to a string.
+pub fn match_type_to_str(cx: &LateContext<'_>, expr_type: Ty<'_>, type_str: &str) -> bool {
+    match expr_type.kind() {
+        TyKind::Adt(adt_def, _) => cx.tcx.def_path_str(adt_def.did()).contains(type_str),
+        TyKind::Ref(_, ty, _) => match_type_to_str(cx, *ty, type_str),
+        _ => false,
+    }
+}
+
+/// Check if a function returns a Result type.
+pub fn returns_result(decl: &FnDecl<'_>) -> bool {
+    if let FnRetTy::Return(ty) = decl.output {
+        matches!(ty.kind, rustc_hir::TyKind::Path(QPath::Resolved(_, path)) if path
+            .segments
+            .last()
+            .map_or(false, |seg| seg.ident.name == sym::Result))
+    } else {
+        false
+    }
+}