minnow-derive 0.1.0

A derive macro for the Minnow library.
Documentation 
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use darling::FromField;
use proc_macro2::TokenStream;
use quote::quote;

use super::{parse_attributes, Model};

pub struct Field {
    pub ident: Option<syn::Ident>,
    pub ty: syn::Type,
    pub model: Option<Model>,
}

impl Field {
    pub fn model(&self) -> TokenStream {
        match self.model {
            Some(Model::Float {
                min,
                max,
                precision,
            }) => quote! { minnow::FloatModel::new( #min ..= #max, #precision ) },
            Some(Model::String { max_length }) => {
                quote! { minnow::StringModel::new( #max_length ) }
            }
            None => quote! {()},
        }
    }
}

impl FromField for Field {
    fn from_field(field: &syn::Field) -> darling::Result<Self> {
        let model = parse_attributes(&field.attrs)?;

        // Final assembly; none of these operations should be fallible.
        Ok(Self {
            ident: field.ident.clone(),
            ty: field.ty.clone(),
            model,
        })
    }
}