freya_router_macro/
hash.rs

1use proc_macro2::TokenStream as TokenStream2;
2use quote::quote;
3use syn::{
4    Ident,
5    Type,
6};
7
8#[derive(Debug)]
9pub struct HashFragment {
10    pub ident: Ident,
11    pub ty: Type,
12}
13
14impl HashFragment {
15    pub fn contains_ident(&self, ident: &Ident) -> bool {
16        self.ident == *ident
17    }
18
19    pub fn parse(&self) -> TokenStream2 {
20        let ident = &self.ident;
21        let ty = &self.ty;
22        quote! {
23            let #ident = <#ty as freya_router::routable::FromHashFragment>::from_hash_fragment(&*hash);
24        }
25    }
26
27    pub fn write(&self) -> TokenStream2 {
28        let ident = &self.ident;
29        quote! {
30            {
31                let __hash = #ident.to_string();
32                if !__hash.is_empty() {
33                    write!(f, "#{}", __hash)?;
34                }
35            }
36        }
37    }
38
39    pub fn parse_from_str<'a>(
40        route_span: proc_macro2::Span,
41        mut fields: impl Iterator<Item = (&'a Ident, &'a Type)>,
42        hash: &str,
43    ) -> syn::Result<Self> {
44        // check if the route has a hash string
45        let Some(hash) = hash.strip_prefix(':') else {
46            return Err(syn::Error::new(
47                route_span,
48                "Failed to parse `:`. Hash fragments must be in the format '#:<field>'",
49            ));
50        };
51
52        let hash_ident = Ident::new(hash, proc_macro2::Span::call_site());
53        let field = fields.find(|(name, _)| *name == &hash_ident);
54
55        let ty = if let Some((_, ty)) = field {
56            ty.clone()
57        } else {
58            return Err(syn::Error::new(
59                route_span,
60                format!("Could not find a field with the name '{hash_ident}'",),
61            ));
62        };
63
64        Ok(Self {
65            ident: hash_ident,
66            ty,
67        })
68    }
69}
freya_router_macro/hash.rs

freya_router_macro/
hash.rs
