From 9917bebb9986c506ae9b0901e030afead54d939a Mon Sep 17 00:00:00 2001
From: Adam Kelly <adam@cthulahoops.org>
Date: Wed, 15 Aug 2018 12:40:52 +0100
Subject: [PATCH] Remove unnecessary mutability in DictProtocol.

---
 vm/src/builtins.rs  | 2 +-
 vm/src/pyobject.rs  | 8 ++++----
 vm/src/sysmodule.rs | 4 ++--
 3 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/vm/src/builtins.rs b/vm/src/builtins.rs
index 2dd9c4a60..132e51c0d 100644
--- a/vm/src/builtins.rs
+++ b/vm/src/builtins.rs
@@ -11,7 +11,7 @@ use super::pyobject::{
 use super::vm::VirtualMachine;
 
 fn get_locals(vm: &mut VirtualMachine) -> PyObjectRef {
-    let mut d = vm.new_dict();
+    let d = vm.new_dict();
     // TODO: implement dict_iter_items?
     let locals = vm.get_locals();
     match locals.borrow().kind {
diff --git a/vm/src/pyobject.rs b/vm/src/pyobject.rs
index 19dd36792..9e0f18b5c 100644
--- a/vm/src/pyobject.rs
+++ b/vm/src/pyobject.rs
@@ -270,8 +270,8 @@ impl AttributeProtocol for PyObjectRef {
     }
 
     fn set_attr(&self, attr_name: &String, value: PyObjectRef) {
-        match self.borrow_mut().kind {
-            PyObjectKind::Instance { ref mut dict } => dict.set_item(attr_name, value),
+        match self.borrow().kind {
+            PyObjectKind::Instance { ref dict } => dict.set_item(attr_name, value),
             ref kind => unimplemented!("load_attr unimplemented for: {:?}", kind),
         };
     }
@@ -280,7 +280,7 @@ impl AttributeProtocol for PyObjectRef {
 pub trait DictProtocol {
     fn contains_key(&self, k: &String) -> bool;
     fn get_item(&self, k: &String) -> PyObjectRef;
-    fn set_item(&mut self, k: &String, v: PyObjectRef);
+    fn set_item(&self, k: &String, v: PyObjectRef);
 }
 
 impl DictProtocol for PyObjectRef {
@@ -302,7 +302,7 @@ impl DictProtocol for PyObjectRef {
         }
     }
 
-    fn set_item(&mut self, k: &String, v: PyObjectRef) {
+    fn set_item(&self, k: &String, v: PyObjectRef) {
         match self.borrow_mut().kind {
             PyObjectKind::Dict {
                 elements: ref mut el,
diff --git a/vm/src/sysmodule.rs b/vm/src/sysmodule.rs
index da454aca5..5886cb0e4 100644
--- a/vm/src/sysmodule.rs
+++ b/vm/src/sysmodule.rs
@@ -8,9 +8,9 @@ use super::pyobject::{DictProtocol, PyContext, PyObjectRef};
 
 pub fn mk_module(ctx: &PyContext) -> PyObjectRef {
     let path = ctx.new_list(None);
-    let mut modules = ctx.new_dict();
+    let modules = ctx.new_dict();
     let sys_name = "sys".to_string();
-    let mut sys_mod = ctx.new_module(&sys_name, ctx.new_scope(None));
+    let sys_mod = ctx.new_module(&sys_name, ctx.new_scope(None));
     modules.set_item(&sys_name, sys_mod.clone());
     sys_mod.set_item(&"modules".to_string(), modules);
     sys_mod.set_item(&"path".to_string(), path);