1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115

extern crate proc_macro;
extern crate proc_macro2;

extern crate syn;

#[macro_use]
extern crate quote;

use proc_macro2::TokenStream;
use syn::{DataStruct, DeriveInput};

#[proc_macro_derive(Insertable)]
pub fn insertable_derive(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
    // Parse the input tokens into a syntax tree
    let input: DeriveInput = syn::parse(input).unwrap();

    let extended = impl_insertable(&input);

    extended.into()
}

fn impl_insertable(ast: &DeriveInput) -> TokenStream {
    let name = &ast.ident;
    let funs;

    match ast.data {
        syn::Data::Struct(ref d) => funs = gen_funs(d),
        _ => panic!("Not as struct"),
    }

    quote!{
        impl Insertable for #name {
            #funs
        }
    }
}

fn gen_funs(data: &DataStruct) -> TokenStream {
    match data.fields {
        syn::Fields::Named(ref fnames) => {
            let mut fields: Vec<String> = Vec::new();

            for n in &fnames.named {
                let b = &n.ident;

                match b {
                    Some(x) => fields.push(x.to_string()),
                    _ => panic!("cannot unwrap()"),
                }
            }

            let fields = fields.iter();

            let fields2 = fnames.named.iter().map(|f| &f.ident);
            quote!{

                    fn fields()->Vec<String>{
                        //#fields
                        vec![#(#fields.to_string()),*]
                    }

                    fn values(&self)-> Vec<Dypes>{
                        vec![#(Dypes::from(self.#fields2.clone())),*]
                    }

            }
        }
        _ => panic!("Not named fields"),
    }
}

#[proc_macro_derive(Queryable)]
pub fn queryable_derive(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
    // Parse the input tokens into a syntax tree
    let input: DeriveInput = syn::parse(input).unwrap();

    let extended = impl_queryable(&input);

    extended.into()
}

fn impl_queryable(ast: &DeriveInput) -> TokenStream {
    let name = &ast.ident;
    let funs;

    match ast.data {
        syn::Data::Struct(ref d) => funs = gen_queryable_funs(d),
        _ => panic!("Not as struct"),
    }

    quote!{
        impl Queryable for #name {
            #funs
        }
    }
}

fn gen_queryable_funs(data: &DataStruct) -> TokenStream {
    match data.fields {
        syn::Fields::Named(ref fnames) => {
            let fields1 = fnames.named.iter().map(|f| &f.ident);
            let fields2 = fnames.named.iter().map(|f| &f.ident);
            let fields3 = fnames.named.iter().map(|f| &f.ident);
            quote!{

                fn new(row: Row) -> Self {
                    Self {
                        #(#fields1: row.get(stringify!(#fields2)).expect(stringify!(#fields3))),*
                    }
                }
            }
        }
        _ => panic!("Not named fields"),
    }
}