strum_macros/macros/
enum_variant_names.rs

1use proc_macro2::TokenStream;
2use quote::quote;
3use syn::{Data, DeriveInput, LitStr};
4
5use crate::helpers::{non_enum_error, HasStrumVariantProperties, HasTypeProperties};
6
7pub fn enum_variant_names_inner(ast: &DeriveInput) -> syn::Result<TokenStream> {
8    let name = &ast.ident;
9    let gen = &ast.generics;
10    let (impl_generics, ty_generics, where_clause) = gen.split_for_impl();
11
12    let variants = match &ast.data {
13        Data::Enum(v) => &v.variants,
14        _ => return Err(non_enum_error()),
15    };
16
17    // Derives for the generated enum
18    let type_properties = ast.get_type_properties()?;
19    let strum_module_path = type_properties.crate_module_path();
20
21    let names = variants
22        .iter()
23        .map(|v| {
24            let props = v.get_variant_properties()?;
25            Ok(props
26                .get_preferred_name(type_properties.case_style, type_properties.prefix.as_ref()))
27        })
28        .collect::<syn::Result<Vec<LitStr>>>()?;
29
30    Ok(quote! {
31        impl #impl_generics #strum_module_path::VariantNames for #name #ty_generics #where_clause {
32            const VARIANTS: &'static [&'static str] = &[ #(#names),* ];
33        }
34    })
35}
strum_macros/macros/enum_variant_names.rs

strum_macros/macros/
enum_variant_names.rs
