| // force-host |
| // no-prefer-dynamic |
| |
| // Proc macros commonly used by tests. |
| // `panic`/`print` -> `panic_bang`/`print_bang` to avoid conflicts with standard macros. |
| |
| #![crate_type = "proc-macro"] |
| |
| extern crate proc_macro; |
| use proc_macro::TokenStream; |
| |
| // Macro that return empty token stream. |
| |
| #[proc_macro] |
| pub fn empty(_: TokenStream) -> TokenStream { |
| TokenStream::new() |
| } |
| |
| #[proc_macro_attribute] |
| pub fn empty_attr(_: TokenStream, _: TokenStream) -> TokenStream { |
| TokenStream::new() |
| } |
| |
| #[proc_macro_derive(Empty, attributes(empty_helper))] |
| pub fn empty_derive(_: TokenStream) -> TokenStream { |
| TokenStream::new() |
| } |
| |
| // Macro that panics. |
| |
| #[proc_macro] |
| pub fn panic_bang(_: TokenStream) -> TokenStream { |
| panic!("panic-bang"); |
| } |
| |
| #[proc_macro_attribute] |
| pub fn panic_attr(_: TokenStream, _: TokenStream) -> TokenStream { |
| panic!("panic-attr"); |
| } |
| |
| #[proc_macro_derive(Panic, attributes(panic_helper))] |
| pub fn panic_derive(_: TokenStream) -> TokenStream { |
| panic!("panic-derive"); |
| } |
| |
| // Macros that return the input stream. |
| |
| #[proc_macro] |
| pub fn identity(input: TokenStream) -> TokenStream { |
| input |
| } |
| |
| #[proc_macro_attribute] |
| pub fn identity_attr(_: TokenStream, input: TokenStream) -> TokenStream { |
| input |
| } |
| |
| #[proc_macro_derive(Identity, attributes(identity_helper))] |
| pub fn identity_derive(input: TokenStream) -> TokenStream { |
| input |
| } |
| |
| // Macros that iterate and re-collect the input stream. |
| |
| #[proc_macro] |
| pub fn recollect(input: TokenStream) -> TokenStream { |
| input.into_iter().collect() |
| } |
| |
| #[proc_macro_attribute] |
| pub fn recollect_attr(_: TokenStream, input: TokenStream) -> TokenStream { |
| input.into_iter().collect() |
| } |
| |
| #[proc_macro_derive(Recollect, attributes(recollect_helper))] |
| pub fn recollect_derive(input: TokenStream) -> TokenStream { |
| input.into_iter().collect() |
| } |
| |
| // Macros that print their input in the original and re-collected forms (if they differ). |
| |
| fn print_helper(input: TokenStream, kind: &str) -> TokenStream { |
| let input_display = format!("{}", input); |
| let input_debug = format!("{:#?}", input); |
| let recollected = input.into_iter().collect(); |
| let recollected_display = format!("{}", recollected); |
| let recollected_debug = format!("{:#?}", recollected); |
| println!("PRINT-{} INPUT (DISPLAY): {}", kind, input_display); |
| if recollected_display != input_display { |
| println!("PRINT-{} RE-COLLECTED (DISPLAY): {}", kind, recollected_display); |
| } |
| println!("PRINT-{} INPUT (DEBUG): {}", kind, input_debug); |
| if recollected_debug != input_debug { |
| println!("PRINT-{} RE-COLLECTED (DEBUG): {}", kind, recollected_debug); |
| } |
| recollected |
| } |
| |
| #[proc_macro] |
| pub fn print_bang(input: TokenStream) -> TokenStream { |
| print_helper(input, "BANG") |
| } |
| |
| #[proc_macro_attribute] |
| pub fn print_attr(_: TokenStream, input: TokenStream) -> TokenStream { |
| print_helper(input, "ATTR") |
| } |
| |
| #[proc_macro_derive(Print, attributes(print_helper))] |
| pub fn print_derive(input: TokenStream) -> TokenStream { |
| print_helper(input, "DERIVE") |
| } |