Rollup merge of #136642 - bjorn3:separate_alloctest_crate, r=cuviper

Put the alloc unit tests in a separate alloctests package

Same rationale as https://github.com/rust-lang/rust/pull/135937. This PR has some extra complexity though as a decent amount of tests are testing internal implementation details rather than the public api. As such I opted to include the modules containing the types under test using `#[path]` into the alloctests package. This means that those modules still need `#[cfg(test)]`, but the rest of liballoc no longer need it.

1 files changed, 93 insertions, 0 deletions

diff --git a/library/alloctests/lib.rs b/library/alloctests/lib.rs
new file mode 100644
index 00000000000..6ce8a6d9ca1
--- /dev/null
+++ b/library/alloctests/lib.rs
@@ -0,0 +1,93 @@
+#![cfg(test)]
+#![allow(unused_attributes)]
+#![unstable(feature = "alloctests", issue = "none")]
+#![no_std]
+// Lints:
+#![deny(unsafe_op_in_unsafe_fn)]
+#![warn(deprecated_in_future)]
+#![warn(missing_debug_implementations)]
+#![allow(explicit_outlives_requirements)]
+#![allow(internal_features)]
+#![allow(rustdoc::redundant_explicit_links)]
+#![warn(rustdoc::unescaped_backticks)]
+#![deny(ffi_unwind_calls)]
+//
+// Library features:
+// tidy-alphabetical-start
+#![feature(alloc_layout_extra)]
+#![feature(allocator_api)]
+#![feature(array_into_iter_constructors)]
+#![feature(assert_matches)]
+#![feature(core_intrinsics)]
+#![feature(exact_size_is_empty)]
+#![feature(extend_one)]
+#![feature(extend_one_unchecked)]
+#![feature(hasher_prefixfree_extras)]
+#![feature(inplace_iteration)]
+#![feature(iter_advance_by)]
+#![feature(iter_next_chunk)]
+#![feature(maybe_uninit_slice)]
+#![feature(maybe_uninit_uninit_array_transpose)]
+#![feature(ptr_internals)]
+#![feature(sized_type_properties)]
+#![feature(slice_iter_mut_as_mut_slice)]
+#![feature(slice_ptr_get)]
+#![feature(slice_range)]
+#![feature(std_internals)]
+#![feature(temporary_niche_types)]
+#![feature(trusted_fused)]
+#![feature(trusted_len)]
+#![feature(trusted_random_access)]
+#![feature(try_reserve_kind)]
+#![feature(try_trait_v2)]
+// tidy-alphabetical-end
+//
+// Language features:
+// tidy-alphabetical-start
+#![feature(cfg_sanitize)]
+#![feature(dropck_eyepatch)]
+#![feature(lang_items)]
+#![feature(min_specialization)]
+#![feature(negative_impls)]
+#![feature(never_type)]
+#![feature(optimize_attribute)]
+#![feature(rustc_allow_const_fn_unstable)]
+#![feature(rustc_attrs)]
+#![feature(staged_api)]
+#![feature(test)]
+#![rustc_preserve_ub_checks]
+// tidy-alphabetical-end
+
+// Allow testing this library
+extern crate alloc as realalloc;
+#[macro_use]
+extern crate std;
+#[cfg(test)]
+extern crate test;
+mod testing;
+use realalloc::*;
+
+// We are directly including collections and raw_vec here as both use non-public
+// methods and fields in tests and as such need to have the types to test in the
+// same crate as the tests themself.
+#[path = "../alloc/src/collections/mod.rs"]
+mod collections;
+
+#[path = "../alloc/src/raw_vec/mod.rs"]
+mod raw_vec;
+
+#[allow(dead_code)] // Not used in all configurations
+pub(crate) mod test_helpers {
+    /// Copied from `std::test_helpers::test_rng`, since these tests rely on the
+    /// seed not being the same for every RNG invocation too.
+    pub(crate) fn test_rng() -> rand_xorshift::XorShiftRng {
+        use std::hash::{BuildHasher, Hash, Hasher};
+        let mut hasher = std::hash::RandomState::new().build_hasher();
+        std::panic::Location::caller().hash(&mut hasher);
+        let hc64 = hasher.finish();
+        let seed_vec =
+            hc64.to_le_bytes().into_iter().chain(0u8..8).collect::<crate::vec::Vec<u8>>();
+        let seed: [u8; 16] = seed_vec.as_slice().try_into().unwrap();
+        rand::SeedableRng::from_seed(seed)
+    }
+}