Check upstream for changes in CI

.github/upstream-sources.json

@@ -0,0 +1,18 @@
+[
+	{ "owner": "rust-lang", "repo": "libm", "tag": "libm-v0.2.11", "path": "src/math/trunc.rs" },
+	{ "owner": "rust-lang", "repo": "libm", "tag": "libm-v0.2.11", "path": "src/math/copysign.rs" },
+	{ "owner": "rust-lang", "repo": "libm", "tag": "libm-v0.2.11", "path": "src/math/round.rs" },
+	{ "owner": "rust-lang", "repo": "rust", "tag": "1.83.0", "path": "library/core/src/time.rs" },
+	{
+		"owner": "rust-lang",
+		"repo": "rust",
+		"tag": "1.82.0",
+		"path": "library/std/src/sys/alloc/wasm.rs"
+	},
+	{
+		"owner": "serde-rs",
+		"repo": "serde",
+		"tag": "v1.0.215",
+		"path": "serde/src/de/impls.rs"
+	}
+]

.github/workflows/upstream.yaml

@@ -0,0 +1,57 @@
+name: Upstream check
+
+on:
+  push:
+    branches: ["main"]
+  pull_request:
+  schedule:
+    - cron: "0 7 * * *"
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref_name }}
+  cancel-in-progress: true
+
+jobs:
+  check:
+    name: Check upstream for changes
+
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: Test
+        uses: actions/github-script@v7
+        with:
+          script: |
+            const upstreamSources = require('./.github/upstream-sources.json')
+            for (const source of upstreamSources) {
+              Promise.all([
+                github.rest.repos.getContent({
+                  owner: source.owner,
+                  repo: source.repo,
+                  path: source.path,
+                  ref: source.tag,
+                }),
+                github.rest.repos
+                  .getLatestRelease({
+                    owner: source.owner,
+                    repo: source.repo,
+                  })
+                  .then((tags) => {
+                    return github.rest.repos.getContent({
+                      owner: source.owner,
+                      repo: source.repo,
+                      path: source.path,
+                      ref: tags.data.tag_name,
+                    })
+                  }),
+              ]).then(([current, latest]) => {
+                if (current.data.sha != latest.data.sha) {
+                  core.setFailed(`
+                    <${current.data.html_url}> has been updated to <${latest.data.html_url}>.
+                    Check if the relevant code needs to be updated and then update the entry in \`.github/upstream-sources.json\`.
+                  `)
+                }
+              })
+            }

benches/benchmark.rs

@@ -103,14 +103,26 @@ pub fn main() {
 		Duration::from_secs_f64(time_stamp) / 1000
 	});
 	benchmark("`Duration::from_secs_f64()` with rounding", |time_stamp| {
-		// See <https://doc.rust-lang.org/1.73.0/src/core/time.rs.html#657-668>.
+		// Inspired by <https://github.com/rust-lang/rust/blob/1.83.0/library/core/src/time.rs#L822-L833>.
+		/// Number of nanoseconds in a second.
+		const NANOS_PER_SEC: u64 = 1_000_000_000;
+		let rhs: u32 = 1000;
 		let time_stamp = Duration::from_secs_f64(time_stamp);
-		let secs = time_stamp.as_secs() / 1000;
-		let carry = time_stamp.as_secs() - secs * 1000;
-		let extra_nanos = (carry * 1_000_000_000 / 1000) as u32;
-		let nanos = time_stamp.subsec_micros()
-			+ u32::from(time_stamp.subsec_nanos() % 1000 > 499)
-			+ extra_nanos;
+		let (secs, extra_secs) = (
+			time_stamp.as_secs() / u64::from(rhs),
+			time_stamp.as_secs() % u64::from(rhs),
+		);
+		let (mut nanos, extra_nanos) = (
+			time_stamp.subsec_nanos() / rhs,
+			time_stamp.subsec_nanos() % rhs,
+		);
+		// CHANGED: Extracted part of the calculation into variable.
+		let extra = extra_secs * NANOS_PER_SEC + u64::from(extra_nanos);
+		nanos += u32::try_from(extra / u64::from(rhs)).unwrap();
+		// CHANGED: Added rounding.
+		nanos += u32::from(extra % u64::from(rhs) >= u64::from(rhs / 2));
+		// CHANGED: Removed check that would fail because of the additional time added
+		// by rounding.
 		Duration::new(secs, nanos)
 	});
 }
@@ -186,19 +198,17 @@ impl F64 {
 }
 
 /// Adjusted [`Duration::from_secs_f64()`].
-///
-/// See <https://doc.rust-lang.org/1.73.0/src/core/time.rs.html#1262-1340>.
 #[expect(warnings, reason = "code is copied")]
 fn adjusted_std(time_stamp: f64) -> Duration {
 	// CHANGED: 1G to 1M.
 	const NANOS_PER_MILLI: u32 = 1_000_000;
 
-	// See <https://doc.rust-lang.org/1.73.0/src/core/time.rs.html#1477-1484>.
+	// See <https://github.com/rust-lang/rust/blob/1.83.0/library/core/src/time.rs#L1694-L1703>.
 	const MANT_BITS: i16 = 52;
 	const EXP_BITS: i16 = 11;
 	const OFFSET: i16 = 44;
 
-	// See <https://doc.rust-lang.org/1.73.0/src/core/time.rs.html#1262-1340>.
+	// See <https://github.com/rust-lang/rust/blob/1.83.0/library/core/src/time.rs#L1480-L1558>.
 	const MIN_EXP: i16 = 1 - (1_i16 << EXP_BITS) / 2;
 	const MANT_MASK: u64 = (1 << MANT_BITS) - 1;
 	const EXP_MASK: u64 = (1 << 1_i16 << EXP_BITS) - 1;
@@ -277,13 +287,17 @@ fn adjusted_std(time_stamp: f64) -> Duration {
 		panic!("can not convert float seconds to Duration: value is either too big or NaN")
 	};
 
-	let secs = millis / 1000;
-	let carry = millis - secs * 1000;
-	let extra_nanos = carry * u64::from(NANOS_PER_MILLI);
-	nanos += extra_nanos as u32;
+	// Inspired by <https://github.com/rust-lang/rust/blob/1.83.0/library/core/src/time.rs#L822-L833>.
+	/// Number of nanoseconds in a second.
+	const NANOS_PER_SEC: u64 = 1_000_000_000;
+	let rhs: u32 = 1000;
+
+	let (secs, extra_secs) = (millis / u64::from(rhs), millis % u64::from(rhs));
+	// CHANGED: Nanos were already calculated during the conversion.
+	nanos += u32::try_from((extra_secs * NANOS_PER_SEC) / u64::from(rhs)).unwrap();
 
 	debug_assert!(
-		nanos < 1_000_000_000,
+		u64::from(nanos) < NANOS_PER_SEC,
 		"impossible amount of nanoseconds found"
 	);
 

src/time/instant.rs

@@ -282,19 +282,27 @@ mod test {
 	struct ControlDuration(Duration);
 
 	impl ControlDuration {
-		/// Implements conversion from `DOMHighResTimeStamp` to [`Duration`] by
-		/// using [`Duration::checked_div()`].
+		/// Implements perfect but expensive conversion from
+		/// `DOMHighResTimeStamp` to [`Duration`].
 		fn new(time_stamp: f64) -> Self {
-			// See <https://doc.rust-lang.org/1.73.0/src/core/time.rs.html#657-668>.
+			// Inspired by <https://github.com/rust-lang/rust/blob/1.83.0/library/core/src/time.rs#L822-L833>.
+			/// Number of nanoseconds in a second.
+			const NANOS_PER_SEC: u64 = 1_000_000_000;
+			let rhs: u32 = 1000;
 			let time_stamp = Duration::from_secs_f64(time_stamp);
-			let secs = time_stamp.as_secs() / 1000;
-			let carry = time_stamp.as_secs() - secs * 1000;
-			#[allow(clippy::as_conversions, clippy::cast_possible_truncation)]
-			let extra_nanos = (carry * 1_000_000_000 / 1000) as u32;
+			let (secs, extra_secs) = (
+				time_stamp.as_secs() / u64::from(rhs),
+				time_stamp.as_secs() % u64::from(rhs),
+			);
+			let (mut nanos, extra_nanos) = (
+				time_stamp.subsec_nanos() / rhs,
+				time_stamp.subsec_nanos() % rhs,
+			);
+			// CHANGED: Extracted part of the calculation into variable.
+			let extra = extra_secs * NANOS_PER_SEC + u64::from(extra_nanos);
+			nanos += u32::try_from(extra / u64::from(rhs)).unwrap();
 			// CHANGED: Added rounding.
-			let nanos = time_stamp.subsec_micros()
-				+ u32::from(time_stamp.subsec_nanos() % 1000 > 499)
-				+ extra_nanos;
+			nanos += u32::from(extra % u64::from(rhs) >= u64::from(rhs / 2));
 			// CHANGED: Removed check that would fail because of the additional time added
 			// by rounding.
 			Self(Duration::new(secs, nanos))

src/time/serde.rs

@@ -2,9 +2,9 @@
 //! compatible with Serde's implementation for [`std::time::SystemTime`].
 //!
 //! This implementation was copied from Serde's
-//! [`Deserialize`](https://github.com/serde-rs/serde/blob/5fa711d75d91173aafc6019e03cf8af6ac9ba7b2/serde/src/de/impls.rs#L2168-L2314),
+//! [`Deserialize`](https://github.com/serde-rs/serde/blob/v1.0.215/serde/src/de/impls.rs#L2282-L2426),
 //! and
-//! [`Serialize`](https://github.com/serde-rs/serde/blob/5fa711d75d91173aafc6019e03cf8af6ac9ba7b2/serde/src/ser/impls.rs#L730-L747)
+//! [`Serialize`](https://github.com/serde-rs/serde/blob/v1.0.215/serde/src/ser/impls.rs#L753-L768)
 //! implementation.
 
 #![allow(warnings)]

tests-web/src/lib.rs

@@ -20,12 +20,11 @@ mod allocator {
 	//! See <https://github.com/rust-lang/rust/blob/1.82.0/library/std/src/sys/alloc/wasm.rs>.
 
 	use core::alloc::{GlobalAlloc, Layout};
-	use core::sync::atomic::{AtomicBool, Ordering};
+
+	use dlmalloc::Dlmalloc;
 
 	/// The allocator.
-	static mut DLMALLOC: dlmalloc::Dlmalloc = dlmalloc::Dlmalloc::new();
-	/// The lock flag.
-	static LOCKED: AtomicBool = AtomicBool::new(false);
+	static mut DLMALLOC: Dlmalloc = Dlmalloc::new();
 	/// Global allocator.
 	#[global_allocator]
 	static ALLOC: System = System;
@@ -37,7 +36,7 @@ mod allocator {
 	unsafe impl GlobalAlloc for System {
 		#[inline]
 		unsafe fn alloc(&self, layout: Layout) -> *mut u8 {
-			let _lock = lock();
+			let _lock = lock::lock();
 			// SAFETY: `DLMALLOC` access is guaranteed to be safe because the lock gives us
 			// unique and non-reentrant access. Calling `malloc()` is safe because
 			// preconditions on this function match the trait method preconditions.
@@ -46,7 +45,7 @@ mod allocator {
 
 		#[inline]
 		unsafe fn alloc_zeroed(&self, layout: Layout) -> *mut u8 {
-			let _lock = lock();
+			let _lock = lock::lock();
 			// SAFETY: `DLMALLOC` access is guaranteed to be safe because the lock gives us
 			// unique and non-reentrant access. Calling `calloc()` is safe because
 			// preconditions on this function match the trait method preconditions.
@@ -55,7 +54,7 @@ mod allocator {
 
 		#[inline]
 		unsafe fn dealloc(&self, ptr: *mut u8, layout: Layout) {
-			let _lock = lock();
+			let _lock = lock::lock();
 			// SAFETY: `DLMALLOC` access is guaranteed to be safe because the lock gives us
 			// unique and non-reentrant access. Calling `free()` is safe because
 			// preconditions on this function match the trait method preconditions.
@@ -64,7 +63,7 @@ mod allocator {
 
 		#[inline]
 		unsafe fn realloc(&self, ptr: *mut u8, layout: Layout, new_size: usize) -> *mut u8 {
-			let _lock = lock();
+			let _lock = lock::lock();
 			// SAFETY: `DLMALLOC` access is guaranteed to be safe because the lock gives us
 			// unique and non-reentrant access. Calling `realloc()` is safe because
 			// preconditions on this function match the trait method preconditions.
@@ -79,22 +78,37 @@ mod allocator {
 		}
 	}
 
-	/// The lock guard.
-	struct DropLock;
+	/// Lock implementation.
+	#[cfg(target_feature = "atomics")]
+	mod lock {
+		use core::sync::atomic::{AtomicBool, Ordering};
 
-	/// Create a [`DropLock`].
-	fn lock() -> DropLock {
-		while LOCKED
-			.compare_exchange_weak(false, true, Ordering::Acquire, Ordering::Relaxed)
-			.is_err()
-		{}
+		/// The lock flag.
+		// CHANGED: using an `AtomicBool` instead of an `AtomicU32`.
+		static LOCKED: AtomicBool = AtomicBool::new(false);
 
-		DropLock
-	}
+		/// The lock guard.
+		pub(super) struct DropLock;
+
+		/// Create a [`DropLock`].
+		pub(super) fn lock() -> DropLock {
+			loop {
+				if !LOCKED.swap(true, Ordering::Acquire) {
+					return DropLock;
+				}
+			}
+		}
 
-	impl Drop for DropLock {
-		fn drop(&mut self) {
-			LOCKED.swap(false, Ordering::Release);
+		impl Drop for DropLock {
+			fn drop(&mut self) {
+				LOCKED.swap(false, Ordering::Release);
+			}
 		}
 	}
+
+	/// Empty lock implementation when threads are not available.
+	#[cfg(not(target_feature = "atomics"))]
+	mod lock {
+		pub(super) fn lock() {}
+	}
 }