Add a public API to get all body locals

This is particularly helpful for the ui tests, but also could be helpful
for Stable MIR users who just want all the locals without needing to
concatenate responses

Author: klinvill

compiler/stable_mir/src/mir/body.rs

@@ -48,6 +48,14 @@ impl Body {
     pub fn internal_locals(&self) -> &[LocalDecl] {
         &self.locals[self.arg_count + 1..]
     }
+
+    /// Convenience function to get all the locals in this function.
+    ///
+    /// Locals are typically accessed via the more specific methods `ret_local`,
+    /// `arg_locals`, and `internal_locals`.
+    pub fn locals(&self) -> &[LocalDecl] {
+        &self.locals
+    }
 }
 
 type LocalDecls = Vec<LocalDecl>;

tests/ui-fulldeps/stable-mir/check_instance.rs

@@ -59,7 +59,7 @@ fn test_body(body: mir::Body) {
     for term in body.blocks.iter().map(|bb| &bb.terminator) {
         match &term.kind {
             Call { func, .. } => {
-                let TyKind::RigidTy(ty) = func.ty(&body.locals).kind() else { unreachable!() };
+                let TyKind::RigidTy(ty) = func.ty(&body.locals()).kind() else { unreachable!() };
                 let RigidTy::FnDef(def, args) = ty else { unreachable!() };
                 let result = Instance::resolve(def, &args);
                 assert!(result.is_ok());