[PATCH 5/8] rust: pin-init: move `InitClosure` out from `__internal`

From: Gary Guo

Date: Wed May 27 2026 - 13:26:11 EST


The `__internal` module is for exposing internal items publicly to
procedural macros (pin-init-internal). Types that are crate-local only can
just have proper visibility and does not need to be in `__internal`.

The type name of `InitClosure` can often shows up in symbol names, this
reduces the length slightly.

Signed-off-by: Gary Guo <gary@xxxxxxxxxxx>
---
rust/pin-init/src/__internal.rs | 30 ------------------------------
rust/pin-init/src/lib.rs | 34 ++++++++++++++++++++++++++++++++--
2 files changed, 32 insertions(+), 32 deletions(-)

diff --git a/rust/pin-init/src/__internal.rs b/rust/pin-init/src/__internal.rs
index 540add6cee8a..56dc655e323e 100644
--- a/rust/pin-init/src/__internal.rs
+++ b/rust/pin-init/src/__internal.rs
@@ -58,36 +58,6 @@ pub const fn new() -> Self {
}
}

-/// Module-internal type implementing `PinInit` and `Init`.
-///
-/// It is unsafe to create this type, since the closure needs to fulfill the same safety
-/// requirement as the `__pinned_init`/`__init` functions.
-pub(crate) struct InitClosure<F, T: ?Sized, E>(pub(crate) F, pub(crate) PhantomInvariant<(E, T)>);
-
-// SAFETY: While constructing the `InitClosure`, the user promised that it upholds the
-// `__init` invariants.
-unsafe impl<T: ?Sized, F, E> Init<T, E> for InitClosure<F, T, E>
-where
- F: FnOnce(*mut T) -> Result<(), E>,
-{
- #[inline]
- unsafe fn __init(self, slot: *mut T) -> Result<(), E> {
- (self.0)(slot)
- }
-}
-
-// SAFETY: While constructing the `InitClosure`, the user promised that it upholds the
-// `__pinned_init` invariants.
-unsafe impl<T: ?Sized, F, E> PinInit<T, E> for InitClosure<F, T, E>
-where
- F: FnOnce(*mut T) -> Result<(), E>,
-{
- #[inline]
- unsafe fn __pinned_init(self, slot: *mut T) -> Result<(), E> {
- (self.0)(slot)
- }
-}
-
/// Token type to signify successful initialization.
///
/// Can only be constructed via the unsafe [`Self::new`] function. The initializer macros use this
diff --git a/rust/pin-init/src/lib.rs b/rust/pin-init/src/lib.rs
index 84099474324e..9732af32795c 100644
--- a/rust/pin-init/src/lib.rs
+++ b/rust/pin-init/src/lib.rs
@@ -1092,6 +1092,36 @@ unsafe fn __pinned_init(self, slot: *mut T) -> Result<(), E> {
}
}

+/// Implement `PinInit` and `Init` for closures.
+///
+/// It is unsafe to create this type, since the closure needs to fulfill the same safety
+/// requirement as the `__pinned_init`/`__init` functions.
+struct InitClosure<F, T: ?Sized, E>(F, __internal::PhantomInvariant<(E, T)>);
+
+// SAFETY: While constructing the `InitClosure`, the user promised that it upholds the
+// `__init` invariants.
+unsafe impl<T: ?Sized, F, E> Init<T, E> for InitClosure<F, T, E>
+where
+ F: FnOnce(*mut T) -> Result<(), E>,
+{
+ #[inline]
+ unsafe fn __init(self, slot: *mut T) -> Result<(), E> {
+ (self.0)(slot)
+ }
+}
+
+// SAFETY: While constructing the `InitClosure`, the user promised that it upholds the
+// `__pinned_init` invariants.
+unsafe impl<T: ?Sized, F, E> PinInit<T, E> for InitClosure<F, T, E>
+where
+ F: FnOnce(*mut T) -> Result<(), E>,
+{
+ #[inline]
+ unsafe fn __pinned_init(self, slot: *mut T) -> Result<(), E> {
+ (self.0)(slot)
+ }
+}
+
/// Creates a new [`PinInit<T, E>`] from the given closure.
///
/// # Safety
@@ -1108,7 +1138,7 @@ unsafe fn __pinned_init(self, slot: *mut T) -> Result<(), E> {
pub const unsafe fn pin_init_from_closure<T: ?Sized, E>(
f: impl FnOnce(*mut T) -> Result<(), E>,
) -> impl PinInit<T, E> {
- __internal::InitClosure(f, __internal::PhantomInvariant::new())
+ InitClosure(f, __internal::PhantomInvariant::new())
}

/// Creates a new [`Init<T, E>`] from the given closure.
@@ -1127,7 +1157,7 @@ unsafe fn __pinned_init(self, slot: *mut T) -> Result<(), E> {
pub const unsafe fn init_from_closure<T: ?Sized, E>(
f: impl FnOnce(*mut T) -> Result<(), E>,
) -> impl Init<T, E> {
- __internal::InitClosure(f, __internal::PhantomInvariant::new())
+ InitClosure(f, __internal::PhantomInvariant::new())
}

/// Changes the to be initialized type.

--
2.54.0