From: Miguel Ojeda Date: Fri, 2 May 2025 21:51:26 +0000 (+0200) Subject: rust: kunit: support KUnit-mapped `assert!` macros in `#[test]`s X-Git-Tag: v6.16-rc1~45^2~11 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=36174d16f3ec072f9e07b6c6d59ba91b2d52f9e2;p=thirdparty%2Fkernel%2Fstable.git rust: kunit: support KUnit-mapped `assert!` macros in `#[test]`s The KUnit `#[test]` support that landed recently is very basic and does not map the `assert*!` macros into KUnit like the doctests do, so they panic at the moment. Thus implement the custom mapping in a similar way to doctests, reusing the infrastructure there. In Rust 1.88.0, the `file()` method in `Span` may be stable [1]. However, it was changed recently (from `SourceFile`), so we need to do something different in previous versions. Thus create a helper for it and use it to get the path. With this, a failing test suite like: #[kunit_tests(my_test_suite)] mod tests { use super::*; #[test] fn my_first_test() { assert_eq!(42, 43); } #[test] fn my_second_test() { assert!(42 >= 43); } } will properly map back to KUnit, printing something like: [ 1.924325] KTAP version 1 [ 1.924421] # Subtest: my_test_suite [ 1.924506] # speed: normal [ 1.924525] 1..2 [ 1.926385] # my_first_test: ASSERTION FAILED at rust/kernel/lib.rs:251 [ 1.926385] Expected 42 == 43 to be true, but is false [ 1.928026] # my_first_test.speed: normal [ 1.928075] not ok 1 my_first_test [ 1.928723] # my_second_test: ASSERTION FAILED at rust/kernel/lib.rs:256 [ 1.928723] Expected 42 >= 43 to be true, but is false [ 1.929834] # my_second_test.speed: normal [ 1.929868] not ok 2 my_second_test [ 1.930032] # my_test_suite: pass:0 fail:2 skip:0 total:2 [ 1.930153] # Totals: pass:0 fail:2 skip:0 total Link: https://github.com/rust-lang/rust/pull/140514 [1] Reviewed-by: David Gow Acked-by: Danilo Krummrich Link: https://lore.kernel.org/r/20250502215133.1923676-2-ojeda@kernel.org [ Required `KUNIT=y` like for doctests. Used the `cfg_attr` from the TODO comment and clarified its comment now that the stabilization is in beta and thus quite likely stable in Rust 1.88.0. Simplified the `new_body` code by introducing a new variable. Added `#[allow(clippy::incompatible_msrv)]`. - Miguel ] Signed-off-by: Miguel Ojeda --- diff --git a/init/Kconfig b/init/Kconfig index 4cdd1049283c1..fb90cc5c44a75 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -140,6 +140,9 @@ config LD_CAN_USE_KEEP_IN_OVERLAY config RUSTC_HAS_COERCE_POINTEE def_bool RUSTC_VERSION >= 108400 +config RUSTC_HAS_SPAN_FILE + def_bool RUSTC_VERSION >= 108800 + config RUSTC_HAS_UNNECESSARY_TRANSMUTES def_bool RUSTC_VERSION >= 108800 diff --git a/rust/Makefile b/rust/Makefile index d62b58d0a55cc..63f3fb2658835 100644 --- a/rust/Makefile +++ b/rust/Makefile @@ -404,7 +404,8 @@ quiet_cmd_rustc_procmacro = $(RUSTC_OR_CLIPPY_QUIET) P $@ -Clink-args='$(call escsq,$(KBUILD_PROCMACROLDFLAGS))' \ --emit=dep-info=$(depfile) --emit=link=$@ --extern proc_macro \ --crate-type proc-macro \ - --crate-name $(patsubst lib%.$(libmacros_extension),%,$(notdir $@)) $< + --crate-name $(patsubst lib%.$(libmacros_extension),%,$(notdir $@)) \ + @$(objtree)/include/generated/rustc_cfg $< # Procedural macros can only be used with the `rustc` that compiled it. $(obj)/$(libmacros_name): $(src)/macros/lib.rs FORCE diff --git a/rust/kernel/kunit.rs b/rust/kernel/kunit.rs index 81833a687b755..78b4acb6595fd 100644 --- a/rust/kernel/kunit.rs +++ b/rust/kernel/kunit.rs @@ -323,7 +323,6 @@ mod tests { #[test] fn rust_test_kunit_example_test() { - #![expect(clippy::eq_op)] assert_eq!(1 + 1, 2); } diff --git a/rust/macros/helpers.rs b/rust/macros/helpers.rs index a3ee27e29a6fe..e2602be402c10 100644 --- a/rust/macros/helpers.rs +++ b/rust/macros/helpers.rs @@ -86,3 +86,20 @@ pub(crate) fn function_name(input: TokenStream) -> Option { } None } + +pub(crate) fn file() -> String { + #[cfg(not(CONFIG_RUSTC_HAS_SPAN_FILE))] + { + proc_macro::Span::call_site() + .source_file() + .path() + .to_string_lossy() + .into_owned() + } + + #[cfg(CONFIG_RUSTC_HAS_SPAN_FILE)] + #[allow(clippy::incompatible_msrv)] + { + proc_macro::Span::call_site().file() + } +} diff --git a/rust/macros/kunit.rs b/rust/macros/kunit.rs index b146c5894e929..971c2c3d849a4 100644 --- a/rust/macros/kunit.rs +++ b/rust/macros/kunit.rs @@ -57,8 +57,8 @@ pub(crate) fn kunit_tests(attr: TokenStream, ts: TokenStream) -> TokenStream { } } - // Add `#[cfg(CONFIG_KUNIT)]` before the module declaration. - let config_kunit = "#[cfg(CONFIG_KUNIT)]".to_owned().parse().unwrap(); + // Add `#[cfg(CONFIG_KUNIT="y")]` before the module declaration. + let config_kunit = "#[cfg(CONFIG_KUNIT=\"y\")]".to_owned().parse().unwrap(); tokens.insert( 0, TokenTree::Group(Group::new(Delimiter::None, config_kunit)), @@ -98,6 +98,8 @@ pub(crate) fn kunit_tests(attr: TokenStream, ts: TokenStream) -> TokenStream { // ``` let mut kunit_macros = "".to_owned(); let mut test_cases = "".to_owned(); + let mut assert_macros = "".to_owned(); + let path = crate::helpers::file(); for test in &tests { let kunit_wrapper_fn_name = format!("kunit_rust_wrapper_{test}"); let kunit_wrapper = format!( @@ -109,6 +111,27 @@ pub(crate) fn kunit_tests(attr: TokenStream, ts: TokenStream) -> TokenStream { " ::kernel::kunit::kunit_case(::kernel::c_str!(\"{test}\"), {kunit_wrapper_fn_name})," ) .unwrap(); + writeln!( + assert_macros, + r#" +/// Overrides the usual [`assert!`] macro with one that calls KUnit instead. +#[allow(unused)] +macro_rules! assert {{ + ($cond:expr $(,)?) => {{{{ + kernel::kunit_assert!("{test}", "{path}", 0, $cond); + }}}} +}} + +/// Overrides the usual [`assert_eq!`] macro with one that calls KUnit instead. +#[allow(unused)] +macro_rules! assert_eq {{ + ($left:expr, $right:expr $(,)?) => {{{{ + kernel::kunit_assert_eq!("{test}", "{path}", 0, $left, $right); + }}}} +}} + "# + ) + .unwrap(); } writeln!(kunit_macros).unwrap(); @@ -147,10 +170,12 @@ pub(crate) fn kunit_tests(attr: TokenStream, ts: TokenStream) -> TokenStream { } } - let mut new_body = TokenStream::from_iter(new_body); - new_body.extend::(kunit_macros.parse().unwrap()); + let mut final_body = TokenStream::new(); + final_body.extend::(assert_macros.parse().unwrap()); + final_body.extend(new_body); + final_body.extend::(kunit_macros.parse().unwrap()); - tokens.push(TokenTree::Group(Group::new(Delimiter::Brace, new_body))); + tokens.push(TokenTree::Group(Group::new(Delimiter::Brace, final_body))); tokens.into_iter().collect() } diff --git a/rust/macros/lib.rs b/rust/macros/lib.rs index b0b86fb9bfab0..bb5df3b730fc2 100644 --- a/rust/macros/lib.rs +++ b/rust/macros/lib.rs @@ -6,6 +6,11 @@ // and thus add a dependency on `include/config/RUSTC_VERSION_TEXT`, which is // touched by Kconfig when the version string from the compiler changes. +// Stable since Rust 1.88.0 under a different name, `proc_macro_span_file`, +// which was added in Rust 1.88.0. This is why `cfg_attr` is used here, i.e. +// to avoid depending on the full `proc_macro_span` on Rust >= 1.88.0. +#![cfg_attr(not(CONFIG_RUSTC_HAS_SPAN_FILE), feature(proc_macro_span))] + #[macro_use] mod quote; mod concat_idents;