From 43b7a7bdbe1064fd6c59f9df41d7daf90ee8a626 Mon Sep 17 00:00:00 2001
From: Noah <33094578+coolreader18@users.noreply.github.com>
Date: Sun, 30 Aug 2020 14:55:16 -0500
Subject: [PATCH] Make into_struct_sequence not clone fields

---
 derive/src/pystructseq.rs | 39 ++++++++++-----------------------------
 vm/src/pyobject.rs        |  8 ++++----
 2 files changed, 14 insertions(+), 33 deletions(-)

diff --git a/derive/src/pystructseq.rs b/derive/src/pystructseq.rs
index d5286ffd9..5c8da6510 100644
--- a/derive/src/pystructseq.rs
+++ b/derive/src/pystructseq.rs
@@ -1,7 +1,7 @@
 use super::Diagnostic;
 use proc_macro2::TokenStream;
 use quote::quote;
-use syn::{DeriveInput, Index};
+use syn::DeriveInput;
 
 pub(crate) fn impl_pystruct_sequence(
     input: DeriveInput,
@@ -15,44 +15,25 @@ pub(crate) fn impl_pystruct_sequence(
         )
     };
 
-    let mut properties = Vec::new();
-    let mut field_names = Vec::new();
-    match fields {
-        syn::Fields::Named(fields) => {
-            for (i, field) in fields.named.iter().enumerate() {
-                let idx = Index::from(i);
-                let field_name = field.ident.as_ref().unwrap();
-                let field_name_str = field_name.to_string();
-                // TODO add doc to the generated property
-                let property = quote! {
-                    class.set_str_attr(
-                        #field_name_str,
-                        ctx.new_readonly_getset(
-                            #field_name_str,
-                            |zelf: &::rustpython_vm::obj::objtuple::PyTuple,
-                             _vm: &::rustpython_vm::VirtualMachine| {
-                                zelf.fast_getitem(#idx)
-                            }
-                       ),
-                    );
-                };
-                properties.push(property);
-                field_names.push(quote!(#field_name));
-            }
-        }
+    let field_names: Vec<_> = match fields {
+        syn::Fields::Named(fields) => fields
+            .named
+            .iter()
+            .map(|field| field.ident.as_ref().unwrap())
+            .collect(),
         _ => bail_span!(
             input,
             "#[pystruct_sequence] can only be on a struct with named fields"
         ),
-    }
+    };
 
     let ty = &input.ident;
     let ret = quote! {
         impl ::rustpython_vm::pyobject::PyStructSequence for #ty {
             const FIELD_NAMES: &'static [&'static str] = &[#(stringify!(#field_names)),*];
-            fn to_tuple(&self, vm: &::rustpython_vm::VirtualMachine,) -> ::rustpython_vm::obj::objtuple::PyTuple {
+            fn into_tuple(self, vm: &::rustpython_vm::VirtualMachine) -> ::rustpython_vm::obj::objtuple::PyTuple {
                 let items = vec![#(::rustpython_vm::pyobject::IntoPyObject::into_pyobject(
-                    ::std::clone::Clone::clone(&self.#field_names),
+                    self.#field_names,
                     vm,
                 )),*];
                 items.into()
diff --git a/vm/src/pyobject.rs b/vm/src/pyobject.rs
index 753b1c496..62fbed9c3 100644
--- a/vm/src/pyobject.rs
+++ b/vm/src/pyobject.rs
@@ -1336,13 +1336,13 @@ pub trait PyClassImpl: PyClassDef {
 }
 
 #[pyimpl]
-pub trait PyStructSequence: PyClassImpl + 'static {
+pub trait PyStructSequence: PyClassImpl + Sized + 'static {
     const FIELD_NAMES: &'static [&'static str];
 
-    fn to_tuple(&self, vm: &VirtualMachine) -> PyTuple;
+    fn into_tuple(self, vm: &VirtualMachine) -> PyTuple;
 
-    fn into_struct_sequence(&self, vm: &VirtualMachine, cls: PyClassRef) -> PyResult<PyTupleRef> {
-        self.to_tuple(vm).into_ref_with_type(vm, cls)
+    fn into_struct_sequence(self, vm: &VirtualMachine, cls: PyClassRef) -> PyResult<PyTupleRef> {
+        self.into_tuple(vm).into_ref_with_type(vm, cls)
     }
 
     #[pymethod(magic)]