From 41fdd280ff1089d1618487d59ed49f83160d2513 Mon Sep 17 00:00:00 2001 From: jyn Date: Sat, 22 Mar 2025 16:09:37 -0400 Subject: [PATCH] rustc_resolve: Test the order that preludes are resolved --- tests/ui/resolve/auxiliary/macro_helpers.rs | 16 ++++ tests/ui/resolve/prelude-order.rs | 89 +++++++++++++++++++++ tests/ui/resolve/prelude-order.stderr | 47 +++++++++++ 3 files changed, 152 insertions(+) create mode 100644 tests/ui/resolve/auxiliary/macro_helpers.rs create mode 100644 tests/ui/resolve/prelude-order.rs create mode 100644 tests/ui/resolve/prelude-order.stderr diff --git a/tests/ui/resolve/auxiliary/macro_helpers.rs b/tests/ui/resolve/auxiliary/macro_helpers.rs new file mode 100644 index 0000000000000..43aa336457de7 --- /dev/null +++ b/tests/ui/resolve/auxiliary/macro_helpers.rs @@ -0,0 +1,16 @@ +/* macro namespace. */ + +extern crate proc_macro; +use proc_macro::*; +use std::str::FromStr; + +const ERROR: &str = "fn helper() { \"helper\" }"; +// https://doc.rust-lang.org/nightly/std/prelude/v1/index.html#attributes +// NOTE: all the bang macros in std are currently unstable. +#[proc_macro_attribute] pub fn test // lang. + (_: TokenStream, _: TokenStream) -> TokenStream { + TokenStream::from_str("fn test_macro() { \"\" }").unwrap() } +// https://doc.rust-lang.org/nightly/reference/attributes.html#built-in-attributes-index +#[proc_macro_attribute] pub fn global_allocator // lang. + (_: TokenStream, _: TokenStream) -> TokenStream { + TokenStream::from_str("fn global_allocator_macro() { \"\" }").unwrap() } diff --git a/tests/ui/resolve/prelude-order.rs b/tests/ui/resolve/prelude-order.rs new file mode 100644 index 0000000000000..a3f194270d483 --- /dev/null +++ b/tests/ui/resolve/prelude-order.rs @@ -0,0 +1,89 @@ +//@ 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 { 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. diff --git a/tests/ui/resolve/prelude-order.stderr b/tests/ui/resolve/prelude-order.stderr new file mode 100644 index 0000000000000..1b9cc94285aa5 --- /dev/null +++ b/tests/ui/resolve/prelude-order.stderr @@ -0,0 +1,47 @@ +error[E0433]: failed to resolve: could not find `inner` in `type_ns` + --> $DIR/prelude-order.rs:61:12 + | +LL | #[type_ns::inner] + | ^^^^^ could not find `inner` in `type_ns` + +error[E0433]: failed to resolve: could not find `inner` in `usize` + --> $DIR/prelude-order.rs:73:10 + | +LL | #[usize::inner] + | ^^^^^ could not find `inner` in `usize` + +error[E0573]: expected type, found crate `Option` + --> $DIR/prelude-order.rs:79:12 + | +LL | fn e2() -> Option { None } + | ^^^^^^^^^^^ not a type + | +help: consider importing this enum instead + | +LL + use std::option::Option; + | + +error[E0308]: mismatched types + --> $DIR/prelude-order.rs:82:1 + | +LL | #[test] + | ^^^^^^^- help: try adding a return type: `-> &'static str` + | | + | expected `()`, found `&str` + | + = note: this error originates in the attribute macro `test` (in Nightly builds, run with -Z macro-backtrace for more info) + +error[E0308]: mismatched types + --> $DIR/prelude-order.rs:86:1 + | +LL | #[global_allocator] + | ^^^^^^^^^^^^^^^^^^^- help: try adding a return type: `-> &'static str` + | | + | expected `()`, found `&str` + | + = note: this error originates in the attribute macro `global_allocator` (in Nightly builds, run with -Z macro-backtrace for more info) + +error: aborting due to 5 previous errors + +Some errors have detailed explanations: E0308, E0433, E0573. +For more information about an error, try `rustc --explain E0308`.