Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Implemented Decodable/Encodable for Cell and RefCell. Fixes #15395. #15411

Merged
merged 1 commit into from
Jul 7, 2014
Merged
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
30 changes: 30 additions & 0 deletions src/libserialize/serialize.rs
Original file line number Diff line number Diff line change
Expand Up @@ -17,6 +17,7 @@ Core encoding and decoding interfaces.
use std::path;
use std::rc::Rc;
use std::gc::{Gc, GC};
use std::cell::{Cell, RefCell};

pub trait Encoder<E> {
// Primitive types:
Expand Down Expand Up @@ -536,6 +537,35 @@ impl<E, D: Decoder<E>> Decodable<D, E> for path::windows::Path {
}
}

impl<E, S: Encoder<E>, T: Encodable<S, E> + Copy> Encodable<S, E> for Cell<T> {
fn encode(&self, s: &mut S) -> Result<(), E> {
self.get().encode(s)
}
}

impl<E, D: Decoder<E>, T: Decodable<D, E> + Copy> Decodable<D, E> for Cell<T> {
fn decode(d: &mut D) -> Result<Cell<T>, E> {
Ok(Cell::new(try!(Decodable::decode(d))))
}
}

// FIXME: #15036
// Should use `try_borrow`, returning a
// `encoder.error("attempting to Encode borrowed RefCell")`
// from `encode` when `try_borrow` returns `None`.

impl<E, S: Encoder<E>, T: Encodable<S, E>> Encodable<S, E> for RefCell<T> {
fn encode(&self, s: &mut S) -> Result<(), E> {
self.borrow().encode(s)
}
}

impl<E, D: Decoder<E>, T: Decodable<D, E>> Decodable<D, E> for RefCell<T> {
fn decode(d: &mut D) -> Result<RefCell<T>, E> {
Ok(RefCell::new(try!(Decodable::decode(d))))
}
}

// ___________________________________________________________________________
// Helper routines
//
Expand Down
55 changes: 55 additions & 0 deletions src/test/run-pass/deriving-encodable-decodable-cell-refcell.rs
Original file line number Diff line number Diff line change
@@ -0,0 +1,55 @@
// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

// This briefuly tests the capability of `Cell` and `RefCell` to implement the
// `Encodable` and `Decodable` traits via `#[deriving(Encodable, Decodable)]`

extern crate serialize;

use std::cell::{Cell, RefCell};
use std::io::MemWriter;
use serialize::{Encodable, Decodable};
use serialize::ebml;
use serialize::ebml::writer::Encoder;
use serialize::ebml::reader::Decoder;

#[deriving(Encodable, Decodable)]
struct A {
baz: int
}

#[deriving(Encodable, Decodable)]
struct B {
foo: Cell<bool>,
bar: RefCell<A>,
}

fn main() {
let obj = B {
foo: Cell::new(true),
bar: RefCell::new( A { baz: 2 } )
};
let mut w = MemWriter::new();
{
let mut e = Encoder::new(&mut w);
match obj.encode(&mut e) {
Ok(()) => (),
Err(e) => fail!("Failed to encode: {}", e)
};
}
let doc = ebml::Doc::new(w.get_ref());
let mut dec = Decoder::new(doc);
let obj2: B = match Decodable::decode(&mut dec) {
Ok(v) => v,
Err(e) => fail!("Failed to decode: {}", e)
};
assert!(obj.foo.get() == obj2.foo.get());
assert!(obj.bar.borrow().baz == obj2.bar.borrow().baz);
}