Auto merge of rust-lang#135937 - bjorn3:separate_coretests_crate, r=jieyouxu,tgross35

Put the core unit tests in a separate coretests package

Having standard library tests in the same package as a standard library crate has bad side effects. It causes the test to have a dependency on a locally built standard library crate, while also indirectly depending on it through libtest. Currently this works out fine in the context of rust's build system as both copies are identical, but for example in cg_clif's tests I've found it basically impossible to compile both copies with the exact same compiler flags and thus the two copies would cause lang item conflicts.

This PR moves the tests of libcore to a separate package which doesn't depend on libcore, thus preventing the duplicate crates even when compiler flags don't exactly match between building the sysroot (for libtest) and building the test itself. The rest of the standard library crates do still have this issue however.

Author: bors

Cargo.lock

@@ -3,6 +3,7 @@ resolver = "1"
 members = [
   "std",
   "sysroot",
+  "coretests",
 ]
 
 exclude = [

Cargo.toml

@@ -15,19 +15,6 @@ edition = "2021"
 test = false
 bench = false
 
-[[test]]
-name = "coretests"
-path = "tests/lib.rs"
-
-[[bench]]
-name = "corebenches"
-path = "benches/lib.rs"
-test = true
-
-[dev-dependencies]
-rand = { version = "0.8.5", default-features = false }
-rand_xorshift = { version = "0.3.0", default-features = false }
-
 [features]
 # Make panics and failed asserts immediately abort without formatting any message
 panic_immediate_abort = []

core/Cargo.toml

@@ -44,7 +44,7 @@
 //!    called. The `lang` attribute is called `eh_personality`.
 
 // Since core defines many fundamental lang items, all tests live in a
-// separate crate, libcoretest (library/core/tests), to avoid bizarre issues.
+// separate crate, coretests (library/coretests), to avoid bizarre issues.
 //
 // Here we explicitly #[cfg]-out this whole crate when testing. If we don't do
 // this, both the generated test artifact and the linked libtest (which

core/src/lib.rs

@@ -0,0 +1,27 @@
+[package]
+name = "coretests"
+version = "0.0.0"
+license = "MIT OR Apache-2.0"
+repository = "https://github.com/rust-lang/rust.git"
+description = "Tests for the Rust Core Library"
+autotests = false
+autobenches = false
+edition = "2021"
+
+[lib]
+path = "lib.rs"
+test = false
+bench = false
+
+[[test]]
+name = "coretests"
+path = "tests/lib.rs"
+
+[[bench]]
+name = "corebenches"
+path = "benches/lib.rs"
+test = true
+
+[dev-dependencies]
+rand = { version = "0.8.5", default-features = false }
+rand_xorshift = { version = "0.3.0", default-features = false }

coretests/Cargo.toml

@@ -0,0 +1 @@
+// Intentionally left empty.

core/benches/any.rs renamed to coretests/benches/any.rs

@@ -1,6 +1,4 @@
-#![feature(bstr)]
-
-use core::ByteStr;
+use core::bstr::ByteStr;
 
 #[test]
 fn test_debug() {

core/benches/array.rs renamed to coretests/benches/array.rs

@@ -11,6 +11,7 @@
 #![feature(async_iter_from_iter)]
 #![feature(async_iterator)]
 #![feature(bigint_helper_methods)]
+#![feature(bstr)]
 #![feature(cell_update)]
 #![feature(clone_to_uninit)]
 #![feature(const_black_box)]
@@ -139,6 +140,7 @@ mod asserting;
 mod async_iter;
 mod atomic;
 mod bool;
+mod bstr;
 mod cell;
 mod char;
 mod clone;