Merge pull request #618 from serde-rs/up

Ask proc_macro_derive to ignore serde attributes
This commit is contained in:
David Tolnay 2016-11-19 14:19:15 -05:00 committed by GitHub
commit 5bd0386b8e
4 changed files with 26 additions and 88 deletions

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@ -22,7 +22,6 @@ with-syn = []
[dependencies]
clippy = { version = "^0.*", optional = true }
post-expansion = "0.2"
quote = "0.3"
serde_codegen_internals = { version = "=0.10.0", default-features = false, path = "../serde_codegen_internals" }
syn = { version = "0.10", features = ["aster", "visit"] }

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@ -27,9 +27,6 @@ extern crate syn;
#[macro_use]
extern crate quote;
#[cfg(feature = "with-syn")]
extern crate post_expansion;
#[cfg(feature = "with-syntex")]
use std::path::Path;
@ -73,8 +70,8 @@ fn syntex_registry() -> syntex::Registry {
reg.add_attr("feature(custom_derive)");
reg.add_attr("feature(custom_attribute)");
reg.add_decorator("derive_Serialize", expand_derive_serialize);
reg.add_decorator("derive_Deserialize", expand_derive_deserialize);
reg.add_decorator("derive_Serialize", shim::expand_derive_serialize);
reg.add_decorator("derive_Deserialize", shim::expand_derive_deserialize);
reg.add_post_expansion_pass(strip_attributes);
@ -112,19 +109,19 @@ pub fn register(reg: &mut rustc_plugin::Registry) {
reg.register_syntax_extension(
syntax::parse::token::intern("derive_Serialize"),
syntax::ext::base::MultiDecorator(
Box::new(expand_derive_serialize)));
Box::new(shim::expand_derive_serialize)));
reg.register_syntax_extension(
syntax::parse::token::intern("derive_Deserialize"),
syntax::ext::base::MultiDecorator(
Box::new(expand_derive_deserialize)));
Box::new(shim::expand_derive_deserialize)));
reg.register_attribute("serde".to_owned(), AttributeType::Normal);
}
macro_rules! shim {
($name:ident $pkg:ident :: $func:ident) => {
fn $func(
pub fn $func(
cx: &mut ::syntax::ext::base::ExtCtxt,
span: ::syntax::codemap::Span,
meta_item: &::syntax::ast::MetaItem,
@ -160,6 +157,7 @@ macro_rules! shim {
use syntax::print::pprust;
let s = pprust::item_to_string(item);
use {syn, $pkg};
let syn_item = syn::parse_macro_input(&s).unwrap();
let expanded = match $pkg::$func(&syn_item) {
Ok(expanded) => expanded.to_string(),
@ -178,72 +176,23 @@ macro_rules! shim {
};
}
shim!(Serialize ser::expand_derive_serialize);
shim!(Deserialize de::expand_derive_deserialize);
mod shim {
shim!(Serialize ser::expand_derive_serialize);
shim!(Deserialize de::expand_derive_deserialize);
}
#[cfg(feature = "with-syn")]
pub fn expand_single_item(item: &str) -> Result<String, String> {
#[doc(hidden)]
/// Not public API. Use the serde_derive crate.
pub fn expand_derive_serialize(item: &str) -> Result<String, String> {
let syn_item = syn::parse_macro_input(item).unwrap();
let (ser, de, syn_item) = strip_serde_derives(syn_item);
let expanded_ser = if ser {
Some(try!(ser::expand_derive_serialize(&syn_item)))
} else {
None
};
let expanded_de = if de {
Some(try!(de::expand_derive_deserialize(&syn_item)))
} else {
None
};
let syn_item = post_expansion::strip_attrs_later(syn_item, &["serde"], "serde");
return Ok(quote!(#expanded_ser #expanded_de #syn_item).to_string());
fn strip_serde_derives(item: syn::MacroInput) -> (bool, bool, syn::MacroInput) {
let mut ser = false;
let mut de = false;
let item = syn::MacroInput {
attrs: item.attrs.into_iter().flat_map(|attr| {
if attr.is_sugared_doc || attr.style != syn::AttrStyle::Outer {
return Some(attr);
}
let (name, nested) = match attr.value {
syn::MetaItem::List(name, nested) => (name, nested),
_ => return Some(attr)
};
if name != "derive" {
return Some(syn::Attribute {
style: syn::AttrStyle::Outer,
value: syn::MetaItem::List(name, nested),
is_sugared_doc: false,
});
}
let rest: Vec<_> = nested.into_iter().filter(|nested| {
use syn::MetaItem::Word;
use syn::NestedMetaItem::MetaItem;
match *nested {
MetaItem(Word(ref word)) if word == "Serialize" => {
ser = true;
false
}
MetaItem(Word(ref word)) if word == "Deserialize" => {
de = true;
false
}
_ => true,
}
}).collect();
if rest.is_empty() {
None
} else {
Some(syn::Attribute {
style: syn::AttrStyle::Outer,
value: syn::MetaItem::List(name, rest),
is_sugared_doc: false,
})
}
}).collect(),
..item
};
(ser, de, item)
}
ser::expand_derive_serialize(&syn_item).map(|derive| derive.to_string())
}
#[cfg(feature = "with-syn")]
#[doc(hidden)]
/// Not public API. Use the serde_derive crate.
pub fn expand_derive_deserialize(item: &str) -> Result<String, String> {
let syn_item = syn::parse_macro_input(item).unwrap();
de::expand_derive_deserialize(&syn_item).map(|derive| derive.to_string())
}

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@ -14,9 +14,6 @@ include = ["Cargo.toml", "src/**/*.rs"]
name = "serde_derive"
proc-macro = true
[dependencies]
post-expansion = "0.2.0"
[dependencies.serde_codegen]
version = "=0.8.17"
path = "../serde_codegen"

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@ -4,27 +4,20 @@
extern crate proc_macro;
extern crate serde_codegen;
#[macro_use]
extern crate post_expansion;
use proc_macro::TokenStream;
#[proc_macro_derive(Serialize)]
#[proc_macro_derive(Serialize, attributes(serde))]
pub fn derive_serialize(input: TokenStream) -> TokenStream {
let item = format!("#[derive(Serialize)]\n{}", input);
match serde_codegen::expand_single_item(&item) {
match serde_codegen::expand_derive_serialize(&input.to_string()) {
Ok(expanded) => expanded.parse().unwrap(),
Err(msg) => panic!(msg),
}
}
#[proc_macro_derive(Deserialize)]
#[proc_macro_derive(Deserialize, attributes(serde))]
pub fn derive_deserialize(input: TokenStream) -> TokenStream {
let item = format!("#[derive(Deserialize)]\n{}", input);
match serde_codegen::expand_single_item(&item) {
match serde_codegen::expand_derive_deserialize(&input.to_string()) {
Ok(expanded) => expanded.parse().unwrap(),
Err(msg) => panic!(msg),
}
}
register_post_expansion!(PostExpansion_serde);