autocxx_parser/
subclass_attrs.rs

1// Copyright 2021 Google LLC
2//
3// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
4// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license
5// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your
6// option. This file may not be copied, modified, or distributed
7// except according to those terms.
8
9use proc_macro2::Ident;
10use quote::ToTokens;
11use syn::Result as ParseResult;
12use syn::{
13    parse::{Parse, ParseStream},
14    token::Comma,
15};
16
17#[derive(Default)]
18pub struct SubclassAttrs {
19    pub self_owned: bool,
20    pub superclass: Option<String>,
21}
22
23impl Parse for SubclassAttrs {
24    fn parse(input: ParseStream) -> ParseResult<Self> {
25        let mut me = Self::default();
26        let mut id = input.parse::<Option<Ident>>()?;
27        while id.is_some() {
28            match id {
29                Some(id) if id == "self_owned" => me.self_owned = true,
30                Some(id) if id == "superclass" => {
31                    let args;
32                    syn::parenthesized!(args in input);
33                    let superclass: syn::LitStr = args.parse()?;
34                    if me.superclass.is_some() {
35                        return Err(syn::Error::new_spanned(
36                            id.into_token_stream(),
37                            "Expected single superclass specification",
38                        ));
39                    }
40                    me.superclass = Some(superclass.value());
41                }
42                Some(id) => {
43                    return Err(syn::Error::new_spanned(
44                        id.into_token_stream(),
45                        "Expected self_owned or superclass",
46                    ))
47                }
48                None => {}
49            };
50            let comma = input.parse::<Option<Comma>>()?;
51            if comma.is_none() {
52                break;
53            }
54            id = input.parse::<Option<Ident>>()?;
55        }
56        Ok(me)
57    }
58}
autocxx_parser/subclass_attrs.rs

autocxx_parser/
subclass_attrs.rs
