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

extern crate proc_macro;

use proc_macro::TokenStream;
use quote::quote;

/// Marks a test function to be executed in a checkers environment.
#[proc_macro_attribute]
pub fn test(args: TokenStream, item: TokenStream) -> TokenStream {
    let input = syn::parse_macro_input!(item as syn::ItemFn);
    let args = syn::parse_macro_input!(args as syn::AttributeArgs);

    let ret = &input.sig.output;
    let name = &input.sig.ident;
    let body = &input.block;
    let attrs = &input.attrs;
    let vis = input.vis;

    for attr in attrs {
        if attr.path.is_ident("test") {
            let msg = "second test attribute is supplied";
            return syn::Error::new_spanned(&attr, msg)
                .to_compile_error()
                .into();
        }
    }

    if !input.sig.inputs.is_empty() {
        let msg = "the test function cannot accept arguments";
        return syn::Error::new_spanned(&input.sig.inputs, msg)
            .to_compile_error()
            .into();
    }

    for arg in args {
        if let syn::NestedMeta::Meta(syn::Meta::Path(path)) = arg {
            let ident = path.get_ident();
            if ident.is_none() {
                let msg = "Must have specified ident";
                return syn::Error::new_spanned(path, msg).to_compile_error().into();
            }
            match ident.unwrap().to_string().to_lowercase().as_str() {
                name => {
                    let msg = format!("Unknown attribute {} is specified", name);
                    return syn::Error::new_spanned(path, msg).to_compile_error().into();
                }
            }
        }
    }

    let result = quote! {
        #[test]
        #(#attrs)*
        #vis fn #name() #ret {
            checkers::STATE.with(|state| {
                state.with(|| {
                    #body
                });

                checkers::verify!(state);
            })
        }
    };

    result.into()
}