edn-derive 0.4.0

Edn (De)Serialization derive macros
Documentation 
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use crate::enums::{generate_variant_deserialization, get_enum_variants};
use crate::structs::{generate_field_deserialization, get_struct_fields};
use proc_macro2::TokenStream as TokenStream2;
use quote::quote;
use syn::{Data, DataEnum, DataStruct, Ident};

pub fn expand(type_name: &Ident, data: &Data) -> TokenStream2 {
    match data {
        Data::Struct(ref data_struct) => expand_struct(type_name, data_struct),
        Data::Enum(ref data_enum) => expand_enum(type_name, data_enum),
        _ => unimplemented!(),
    }
}

fn expand_struct(struct_name: &Ident, data_struct: &DataStruct) -> TokenStream2 {
    let struct_fields = get_struct_fields(data_struct);

    let deserialized_fields = generate_field_deserialization(&struct_fields);

    quote! {
        impl edn_rs::Deserialize for #struct_name {
            fn deserialize(edn: &edn_rs::Edn) -> Result<Self, edn_rs::EdnError> {
                Ok(Self {
                    #deserialized_fields
                })
            }
        }
    }
}

fn expand_enum(enum_name: &Ident, data_enum: &DataEnum) -> TokenStream2 {
    let enum_variants = get_enum_variants(data_enum);

    let deserialized_variants = generate_variant_deserialization(enum_name, &enum_variants);

    quote! {
        impl edn_rs::Deserialize for #enum_name {
            fn deserialize(edn: &edn_rs::Edn) -> Result<Self, edn_rs::EdnError> {
                match edn {
                    edn_rs::Edn::Key(k) => match &k[..] {
                        #deserialized_variants
                        _ => Err(edn_rs::EdnError::Deserialize(format!(
                                "couldn't convert {} keyword into enum",
                                k
                        ))),
                    },
                    edn_rs::Edn::Str(s) => match &s[..] {
                        #deserialized_variants
                        _ => Err(edn_rs::EdnError::Deserialize(format!(
                                "couldn't convert {} string into enum",
                                s
                        ))),
                    },
                    _ => Err(edn_rs::EdnError::Deserialize(format!(
                                "couldn't convert {} into enum",
                                edn
                    ))),
                }
            }
        }
    }
}