blob: 86750e177e2c0ad5795ba17d0820cb7cb585642e (
plain)
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
|
#![feature(proc_macro_span)]
extern crate proc_macro;
use std::fs;
use proc_macro::TokenStream;
use quote::quote;
#[proc_macro_derive(Model, attributes(model))]
pub fn model_derive(input: TokenStream) -> TokenStream {
// Construct a representation of Rust code as a syntax tree
// that we can manipulate
let ast = syn::parse(input).unwrap();
// Build the trait implementation
impl_model(&ast)
}
fn impl_model(ast: &syn::DeriveInput) -> TokenStream {
let name = &ast.ident;
let gen = quote! {
use tosin::db::models::ModelMeta;
impl #name {
pub const META: ModelMeta = ModelMeta {
name: stringify!(#name),
fields: &[],
};
}
};
gen.into()
}
#[proc_macro]
pub fn gather_migrations(_input: TokenStream) -> TokenStream {
let call_site = proc_macro::Span::call_site();
let call_site_file = call_site.source_file();
let call_site_path = call_site_file.path();
if !call_site_file.is_real() {
panic!("call site does not have a real path");
}
let migrations_dir = call_site_path.parent().unwrap();
let migrations: Vec<syn::Ident> = migrations_dir.read_dir()
.unwrap()
.map(Result::unwrap)
.map(|x| x.path().file_stem().unwrap().to_string_lossy().into_owned())
.filter(|x| x != "mod")
.map(|x| syn::parse_str(&x).unwrap())
.collect();
let gen = quote! {
#( mod #migrations; )*
pub const ALL: &[Migration] = &[
#(#migrations::MIGRATION),*
];
};
gen.into()
}
#[proc_macro]
pub fn gather_models(_input: TokenStream) -> TokenStream {
let call_site = proc_macro::Span::call_site();
let call_site_file = call_site.source_file();
let call_site_path = call_site_file.path();
if !call_site_file.is_real() {
panic!("call site does not have a real path");
}
let call_site_ast = syn::parse_file(&fs::read_to_string(call_site_path).unwrap()).unwrap();
let models = call_site_ast.items.iter()
.filter_map(|item| if let syn::Item::Struct(item) = item { Some(item) } else { None })
.filter(|item| item.attrs.iter().any(|attr| {
let attr = if let Ok(syn::Meta::List(attr)) = attr.parse_meta() { attr } else { return false; };
if attr.path.get_ident().map_or(false, |hopefully_derive| hopefully_derive == "derive") {
let mut derived = attr.nested.iter()
.filter_map(|derived| if let syn::NestedMeta::Meta(derived) = derived { Some(derived) } else { None });
derived.any(|derived| derived.path().get_ident().map_or(false, |hopefully_model| hopefully_model == "Model"))
} else {
false
}
}))
.map(|item| &item.ident);
let gen = quote! {
pub const ALL: &[tosin::db::models::ModelMeta] = &[
#(#models::META),*
];
};
gen.into()
}
|