Add #[heapsize]/#[derive(HeapSizeOf)] plugin to auto-derive HeapSizeOf impls

(fixes #5914)
This commit is contained in:
Manish Goregaokar 2015-03-31 08:32:11 +05:30
parent 05212b702d
commit f4bc92526a
3 changed files with 87 additions and 2 deletions

View file

@ -0,0 +1,54 @@
use syntax::ext::base::{Annotatable, ExtCtxt};
use syntax::codemap::Span;
use syntax::ptr::P;
use syntax::ast::*;
use syntax::attr::AttrMetaMethods;
use syntax::ext::build::AstBuilder;
use syntax::ext::deriving::generic::*;
pub fn expand_heapsize(cx: &mut ExtCtxt, span: Span, mitem: &MetaItem, item: Annotatable, push: &mut FnMut(Annotatable)) {
let trait_def = TraitDef {
span: span,
attributes: Vec::new(),
path: ty::Path::new(vec!("util", "mem", "HeapSizeOf")),
additional_bounds: Vec::new(),
generics: ty::LifetimeBounds::empty(),
methods: vec![
MethodDef {
name: "heap_size_of_children",
generics: ty::LifetimeBounds::empty(),
explicit_self: ty::borrowed_explicit_self(),
args: vec!(),
ret_ty: ty::Literal(ty::Path::new_local("usize")),
attributes: vec!(),
is_unsafe: false,
combine_substructure: combine_substructure(Box::new(heapsize_substructure))
}
],
associated_types: vec![],
};
trait_def.expand(cx, mitem, &item, push)
}
fn heapsize_substructure(cx: &mut ExtCtxt, trait_span: Span, substr: &Substructure) -> P<Expr> {
let fields = match *substr.fields {
Struct(ref fs) | EnumMatching(_, _, ref fs) => fs,
_ => cx.span_bug(trait_span, "impossible substructure in `heapsize`")
};
fields.iter().fold(cx.expr_usize(trait_span, 0),
|acc, ref item| {
if item.attrs.iter()
.find(|ref a| a.check_name("ignore_heapsize"))
.is_some() {
acc
} else {
cx.expr_binary(item.span, BiAdd, acc,
cx.expr_method_call(item.span,
item.self_.clone(),
substr.method_ident,
Vec::new()))
}
})
}

View file

@ -8,8 +8,7 @@
//!
//! - `#[privatize]` : Forces all fields in a struct/enum to be private
//! - `#[jstraceable]` : Auto-derives an implementation of `JSTraceable` for a struct in the script crate
//! - `#[must_root]` : Prevents data of the marked type from being used on the stack. See the lints module for more
//! details
//! - `#[must_root]` : Prevents data of the marked type from being used on the stack. See the lints module for more details
//! - `#[dom_struct]` : Implies `#[privatize]`,`#[jstraceable]`, and `#[must_root]`.
//! Use this for structs that correspond to a DOM type
@ -31,6 +30,8 @@ use syntax::parse::token::intern;
// Public for documentation to show up
/// Handles the auto-deriving for `#[jstraceable]`
pub mod jstraceable;
/// Handles the auto-deriving for `#[heapsize]`
pub mod heapsize;
/// Autogenerates implementations of Reflectable on DOM structs
pub mod reflector;
pub mod lints;
@ -43,6 +44,8 @@ pub fn plugin_registrar(reg: &mut Registry) {
reg.register_syntax_extension(intern("dom_struct"), MultiModifier(box jstraceable::expand_dom_struct));
reg.register_syntax_extension(intern("jstraceable"), MultiDecorator(box jstraceable::expand_jstraceable));
reg.register_syntax_extension(intern("_generate_reflector"), MultiDecorator(box reflector::expand_reflector));
reg.register_syntax_extension(intern("derive_HeapSizeOf"), MultiDecorator(box heapsize::expand_heapsize));
reg.register_syntax_extension(intern("heapsize"), MultiDecorator(box heapsize::expand_heapsize));
reg.register_macro("to_lower", casing::expand_lower);
reg.register_macro("to_upper", casing::expand_upper);
reg.register_lint_pass(box lints::transmute_type::TransmutePass as LintPassObject);