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