| //@ proc-macro:macro_helpers.rs |
| //@ compile-flags: --crate-type=lib |
| |
| /* There are 5 preludes and 3 namespaces. Test the order in which they are resolved. |
| * See https://doc.rust-lang.org/nightly/reference/names/preludes.html. |
| * |
| * Macros cannot be in the type or value namespace. |
| * Tools and extern crates cannot be in the macro or value namespace. |
| * |
| * Test the following truth tables: |
| |
| Type: |
| | ...... | tool | extern | macro | lang | libs | |
| | tool | N/A | mirror |
| | extern | extern | N/A | universe |
| | macro | N/A | N/A | N/A | |
| | lang | tool | extern | N/A | N/A | |
| | libs | tool | extern | N/A | X | N/A | |
| |
| Macro: |
| | ...... | tool | extern | macro | lang | libs | |
| | tool | N/A | mirror |
| | extern | N/A | N/A | universe |
| | macro | N/A | N/A | N/A | |
| | lang | N/A | N/A | macro | N/A | |
| | libs | N/A | N/A | macro | X | N/A | |
| |
| Value: N/A. Only libs has items in the value namespace. |
| |
| † ambiguous |
| X don't care (controlled namespace with no overlap) |
| |
| * Types are tested with `#[name::inner]`. Macros are tested with `#[name]`. |
| * WARNING: I have found in testing that attribute macros give ambiguity errors in some contexts |
| * instead of choosing a prelude. Have not been able to replicate. |
| * |
| * There should be 7 total tests. |
| * See `rustc_resolve::ident::visit_scopes` for more information, |
| * and for a definition of "controlled namespace". |
| */ |
| |
| #![feature(register_tool)] |
| |
| /* tool prelude */ |
| #![register_tool(type_ns)] // extern prelude. type. |
| #![register_tool(i8)] // lang prelude. type. |
| #![register_tool(Sync)] // libs prelude. type. |
| |
| /* extern prelude */ |
| extern crate macro_helpers as type_ns; // tool prelude. type. |
| extern crate macro_helpers as usize; // lang prelude. type. |
| extern crate macro_helpers as Option; // libs prelude. type. |
| |
| /* macro_use prelude */ |
| #[macro_use] |
| extern crate macro_helpers as _; |
| |
| /* lang and libs implicitly in scope */ |
| |
| // tool/extern -> extern |
| #[type_ns::inner] //~ ERROR could not find `inner` in `type_ns` |
| fn t1() {} |
| |
| // tool/lang -> tool |
| #[i8::inner] // ok |
| fn t2() {} |
| |
| // tool/libs -> tool |
| #[Sync::not_real] // ok |
| fn t3() {} |
| |
| // extern/lang -> extern |
| #[usize::inner] //~ ERROR could not find `inner` in `usize` |
| fn e1() {} // NOTE: testing with `-> usize` isn't valid, crates aren't considered in that scope |
| // (unless they have generic arguments, for some reason.) |
| |
| // extern/libs -> extern |
| // https://github.com/rust-lang/rust/issues/139095 |
| fn e2() -> Option<i32> { None } //~ ERROR: expected type, found crate |
| |
| // macro/libs -> macro |
| #[test] //~ ERROR mismatched types |
| fn m1() {} |
| |
| // macro/lang -> macro |
| #[global_allocator] //~ ERROR mismatched types |
| fn m2() {} |
| |
| // lang/libs: no items that currently overlap, in either macro or type ns. |
