Test no_std MSRV in CI

.github/workflows/main.yml

@@ -540,13 +540,22 @@ jobs:
   msrv-lib:
     name: Check MSRV for libraries
     runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        target:
+          - x86_64-unknown-linux-gnu
+          - wasm32-unknown-unknown
+        features:
+          - --no-default-features
+          - ""
     defaults:
       run:
         working-directory: crates/msrv/lib
     steps:
     - uses: actions/checkout@v4
-    - run: rustup update --no-self-update 1.57 && rustup default 1.57
-    - run: cargo build
+    - run: rustup update --no-self-update 1.57 && rustup default 1.57 && rustup target add ${{ matrix.target }}
+    - run: cargo build --target ${{ matrix.target }} ${{ matrix.features }}
 
   msrv-cli:
     name: Check MSRV for CLI tools

crates/msrv/cli/Cargo.toml

@@ -6,9 +6,3 @@ version = "0.0.0"
 
 [dependencies]
 wasm-bindgen-cli = { path = "../../cli" }
-wasm-bindgen-cli-support = { path = "../../cli-support" }
-wasm-bindgen-externref-xform = { path = "../../externref-xform" }
-wasm-bindgen-multi-value-xform = { path = "../../multi-value-xform" }
-wasm-bindgen-threads-xform = { path = "../../threads-xform" }
-wasm-bindgen-wasm-conventions = { path = "../../wasm-conventions" }
-wasm-bindgen-wasm-interpreter = { path = "../../wasm-interpreter" }

crates/msrv/lib/Cargo.toml

@@ -4,21 +4,24 @@ name = "msrv-library-test"
 publish = false
 version = "0.0.0"
 
+[features]
+default = ["std"]
+std = [
+  "wasm-bindgen/std",
+  "js-sys/std",
+  "wasm-bindgen-futures/std",
+  "web-sys/std",
+  "wasm-bindgen-test/std",
+]
+
 [dependencies]
-js-sys = { path = "../../js-sys" }
-wasm-bindgen = { path = "../../../" }
-wasm-bindgen-backend = { path = "../../backend" }
-wasm-bindgen-futures = { path = "../../futures" }
-wasm-bindgen-macro = { path = "../../macro" }
-wasm-bindgen-macro-support = { path = "../../macro-support" }
-wasm-bindgen-shared = { path = "../../shared" }
-wasm-bindgen-test = { path = "../../test" }
-wasm-bindgen-test-macro = { path = "../../test-macro" }
-web-sys = { path = "../../web-sys" }
+js-sys = { path = "../../js-sys", default-features = false }
+wasm-bindgen = { path = "../../../", default-features = false }
+wasm-bindgen-futures = { path = "../../futures", default-features = false }
+wasm-bindgen-test = { path = "../../test", default-features = false }
+web-sys = { path = "../../web-sys", default-features = false }
 
+# Pinned sub-dependencies for MSRV
 bumpalo = "=3.12.0"
 log = "=0.4.18"
-scoped-tls = "=1.0.0"
-
-[patch.crates-io]
-wasm-bindgen = { path = "../../../" }
+scoped-tls = { version = "=1.0.0", optional = false }

crates/test/src/rt/scoped_tls.rs

@@ -37,7 +37,7 @@ impl<T> ScopedKey<T> {
     #[doc(hidden)]
     /// # Safety
     /// `inner` must only be accessed through `ScopedKey`'s API
-    pub const unsafe fn new(inner: &'static Wrapper<Cell<*const ()>>) -> Self {
+    pub(super) const unsafe fn new(inner: &'static Wrapper<Cell<*const ()>>) -> Self {
         Self {
             inner,
             _marker: PhantomData,

src/lib.rs

@@ -1595,20 +1595,23 @@ pub mod __rt {
     /// Wrapper around [`::once_cell::unsync::Lazy`] adding some compatibility methods with
     /// [`std::thread::LocalKey`] and adding `Send + Sync` when `atomics` is not enabled.
     #[cfg(not(feature = "std"))]
-    pub struct LazyCell<T>(::once_cell::unsync::Lazy<T>);
+    pub struct LazyCell<T, F = fn() -> T>(::once_cell::unsync::Lazy<T, F>);
 
     #[cfg(all(not(target_feature = "atomics"), not(feature = "std")))]
-    unsafe impl<T> Sync for LazyCell<T> {}
+    unsafe impl<T, F> Sync for LazyCell<T, F> {}
 
     #[cfg(all(not(target_feature = "atomics"), not(feature = "std")))]
-    unsafe impl<T> Send for LazyCell<T> {}
+    unsafe impl<T, F> Send for LazyCell<T, F> {}
 
     #[cfg(not(feature = "std"))]
-    impl<T> LazyCell<T> {
-        pub const fn new(init: fn() -> T) -> LazyCell<T> {
+    impl<T, F> LazyCell<T, F> {
+        pub const fn new(init: F) -> LazyCell<T, F> {
             Self(::once_cell::unsync::Lazy::new(init))
         }
+    }
 
+    #[cfg(not(feature = "std"))]
+    impl<T, F: FnOnce() -> T> LazyCell<T, F> {
         pub(crate) fn try_with<R>(
             &self,
             f: impl FnOnce(&T) -> R,