init: allow nonstandard_style for generated accessor/value

CHANGELOG.md

@@ -38,6 +38,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Corrected `T: Sized` bounds to `T: ?Sized` in the generated `PinnedDrop`
   check by `#[pin_data]`.
+- `#[pin_data]` no longer produces additional `non_snake_case` warnings if field names
+  are not of snake case. Standard field definition warnings are unaffected.
+- `init!` and `pin_init!` no longer produce `non_snake_case` warnings if field names
+  are not of snake case. Warnings on the struct definition are unaffected.
 
 ## [0.0.10] - 2025-08-19
 

internal/src/init.rs

@@ -240,13 +240,25 @@ fn init_fields(
         };
         let init = match kind {
             InitializerKind::Value { ident, value } => {
-                let mut value_ident = ident.clone();
-                let value_prep = value.as_ref().map(|value| &value.1).map(|value| {
-                    // Setting the span of `value_ident` to `value`'s span improves error messages
-                    // when the type of `value` is wrong.
-                    value_ident.set_span(value.span());
-                    quote!(let #value_ident = #value;)
-                });
+                let (value_ident, value_prep) = match value.as_ref() {
+                    None => {
+                        // This is of short-hand syntax, so just use the identifier directly.
+                        (ident.clone(), None)
+                    }
+                    Some((_, value)) => {
+                        // We have an expression. Evaluate it to a local variable first, outside
+                        // `unsafe {}` block.
+                        //
+                        // Setting the span of `value_ident` to `value`'s span improves error messages
+                        // when the type of `value` is wrong.
+                        (
+                            format_ident!("value", span = value.span()),
+                            Some(quote! {
+                                let value = #value;
+                            }),
+                        )
+                    }
+                };
                 // Again span for better diagnostics
                 let write = quote_spanned!(ident.span()=> ::core::ptr::write);
                 // NOTE: the field accessor ensures that the initialized field is properly aligned.
@@ -273,7 +285,9 @@ fn init_fields(
                         unsafe { #write(&raw mut (*#slot).#ident, #value_ident) };
                     }
                     #(#cfgs)*
-                    #[allow(unused_variables)]
+                    // Allow `non_snake_case` since the same warning is going to be reported for
+                    // the struct field.
+                    #[allow(unused_variables, non_snake_case)]
                     let #ident = #accessor;
                 }
             }
@@ -325,7 +339,9 @@ fn init_fields(
                         #value_init
                     }
                     #(#cfgs)*
-                    #[allow(unused_variables)]
+                    // Allow `non_snake_case` since the same warning is going to be reported for
+                    // the struct field.
+                    #[allow(unused_variables, non_snake_case)]
                     let #ident = #accessor;
                 }
             }

internal/src/pin_data.rs

@@ -164,7 +164,10 @@ fn generate_unpin_impl(
     quote! {
         // This struct will be used for the unpin analysis. It is needed, because only structurally
         // pinned fields are relevant whether the struct should implement `Unpin`.
-        #[allow(dead_code)] // The fields below are never used.
+        #[allow(
+            dead_code, // The fields below are never used.
+            non_snake_case // The warning will be emitted on the struct definition.
+        )]
         struct __Unpin #generics_with_pin_lt
         #where_token
             #predicates
@@ -302,7 +305,9 @@ fn generate_projections(
     let docs = format!(" Pin-projections of [`{ident}`]");
     quote! {
         #[doc = #docs]
-        #[allow(dead_code)]
+        // Allow `non_snake_case` since the same warning will be emitted on
+        // the struct definition.
+        #[allow(dead_code, non_snake_case)]
         #[doc(hidden)]
         #vis struct #projection #generics_with_pin_lt {
             #(#fields_decl)*
@@ -395,6 +400,9 @@ fn generate_the_pin_data(
             ///   to deallocate.
             #pin_safety
             #(#attrs)*
+            // Allow `non_snake_case` since the same warning will be emitted on
+            // the struct definition.
+            #[allow(non_snake_case)]
             #vis unsafe fn #ident<E>(
                 self,
                 slot: *mut #ty,

tests/nonstandard_style.rs

@@ -0,0 +1,62 @@
+//! Tests that no extra warnings are emitted for non-snake-case fields when using
+//! `#[pin_data]`, `init!` or `pin_init!`.
+//!
+//! See: https://github.com/Rust-for-Linux/pin-init/issues/125
+
+#![deny(nonstandard_style)]
+#![allow(dead_code)]
+#![cfg_attr(USE_RUSTC_FEATURES, feature(lint_reasons))]
+#![cfg_attr(USE_RUSTC_FEATURES, feature(raw_ref_op))]
+
+use pin_init::*;
+
+#[allow(non_snake_case)]
+struct Foo {
+    NON_STANDARD_A: usize,
+    nonStandardB: Bar,
+}
+
+#[allow(non_snake_case)]
+struct Bar {
+    Non_Standard_C: usize,
+}
+
+impl Foo {
+    fn new() -> impl Init<Self> {
+        init!(Self {
+            NON_STANDARD_A: {
+                #[expect(
+                    nonstandard_style,
+                    reason = "User code warnings should not be suppressed"
+                )]
+                (0..2).map(|NonStandardInUserCode| NonStandardInUserCode + 1).sum()
+            },
+            nonStandardB <- init!(Bar { Non_Standard_C: 42 }),
+        })
+    }
+}
+
+// Non-camel-case struct name should not produce warnings.
+#[allow(nonstandard_style)]
+#[pin_data]
+struct non_standard_baz {
+    NON_STANDARD: usize,
+    #[pin]
+    nonStandardPin: usize,
+}
+
+impl non_standard_baz {
+    fn new(a: impl PinInit<usize>) -> impl PinInit<Self> {
+        pin_init!(Self {
+            NON_STANDARD: {
+                #[expect(
+                    nonstandard_style,
+                    reason = "User code warnings should not be suppressed"
+                )]
+                let NON_STANDARD_IN_USER_CODE = 41;
+                NON_STANDARD_IN_USER_CODE + 1
+            },
+            nonStandardPin <- a,
+        })
+    }
+}

tests/ui/expand/many_generics.expanded.rs

@@ -13,7 +13,7 @@ where
     _pin: PhantomPinned,
 }
 /// Pin-projections of [`Foo`]
-#[allow(dead_code)]
+#[allow(dead_code, non_snake_case)]
 #[doc(hidden)]
 struct FooProjection<
     '__pin,
@@ -92,6 +92,7 @@ const _: () = {
         /// - `slot` is a valid pointer to uninitialized memory.
         /// - the caller does not touch `slot` when `Err` is returned, they are only permitted
         ///   to deallocate.
+        #[allow(non_snake_case)]
         unsafe fn array<E>(
             self,
             slot: *mut [u8; 1024 * 1024],
@@ -113,6 +114,7 @@ const _: () = {
         /// - `slot` is a valid pointer to uninitialized memory.
         /// - the caller does not touch `slot` when `Err` is returned, they are only permitted
         ///   to deallocate.
+        #[allow(non_snake_case)]
         unsafe fn r<E>(
             self,
             slot: *mut &'b mut [&'a mut T; SIZE],
@@ -135,6 +137,7 @@ const _: () = {
         /// - the caller does not touch `slot` when `Err` is returned, they are only permitted
         ///   to deallocate.
         /// - `slot` will not move until it is dropped, i.e. it will be pinned.
+        #[allow(non_snake_case)]
         unsafe fn _pin<E>(
             self,
             slot: *mut PhantomPinned,
@@ -179,7 +182,7 @@ const _: () = {
     {
         type Datee = Foo<'a, 'b, T, SIZE>;
     }
-    #[allow(dead_code)]
+    #[allow(dead_code, non_snake_case)]
     struct __Unpin<'__pin, 'a, 'b: 'a, T: Bar<'b> + ?Sized + 'a, const SIZE: usize = 0>
     where
         T: Bar<'a, 1>,

tests/ui/expand/pin-data.expanded.rs

@@ -5,7 +5,7 @@ struct Foo {
     _pin: PhantomPinned,
 }
 /// Pin-projections of [`Foo`]
-#[allow(dead_code)]
+#[allow(dead_code, non_snake_case)]
 #[doc(hidden)]
 struct FooProjection<'__pin> {
     array: &'__pin mut [u8; 1024 * 1024],
@@ -51,6 +51,7 @@ const _: () = {
         /// - `slot` is a valid pointer to uninitialized memory.
         /// - the caller does not touch `slot` when `Err` is returned, they are only permitted
         ///   to deallocate.
+        #[allow(non_snake_case)]
         unsafe fn array<E>(
             self,
             slot: *mut [u8; 1024 * 1024],
@@ -73,6 +74,7 @@ const _: () = {
         /// - the caller does not touch `slot` when `Err` is returned, they are only permitted
         ///   to deallocate.
         /// - `slot` will not move until it is dropped, i.e. it will be pinned.
+        #[allow(non_snake_case)]
         unsafe fn _pin<E>(
             self,
             slot: *mut PhantomPinned,
@@ -101,7 +103,7 @@ const _: () = {
     unsafe impl ::pin_init::__internal::PinData for __ThePinData {
         type Datee = Foo;
     }
-    #[allow(dead_code)]
+    #[allow(dead_code, non_snake_case)]
     struct __Unpin<'__pin> {
         __phantom_pin: ::core::marker::PhantomData<fn(&'__pin ()) -> &'__pin ()>,
         __phantom: ::core::marker::PhantomData<fn(Foo) -> Foo>,

tests/ui/expand/pinned_drop.expanded.rs

@@ -5,7 +5,7 @@ struct Foo {
     _pin: PhantomPinned,
 }
 /// Pin-projections of [`Foo`]
-#[allow(dead_code)]
+#[allow(dead_code, non_snake_case)]
 #[doc(hidden)]
 struct FooProjection<'__pin> {
     array: &'__pin mut [u8; 1024 * 1024],
@@ -51,6 +51,7 @@ const _: () = {
         /// - `slot` is a valid pointer to uninitialized memory.
         /// - the caller does not touch `slot` when `Err` is returned, they are only permitted
         ///   to deallocate.
+        #[allow(non_snake_case)]
         unsafe fn array<E>(
             self,
             slot: *mut [u8; 1024 * 1024],
@@ -73,6 +74,7 @@ const _: () = {
         /// - the caller does not touch `slot` when `Err` is returned, they are only permitted
         ///   to deallocate.
         /// - `slot` will not move until it is dropped, i.e. it will be pinned.
+        #[allow(non_snake_case)]
         unsafe fn _pin<E>(
             self,
             slot: *mut PhantomPinned,
@@ -101,7 +103,7 @@ const _: () = {
     unsafe impl ::pin_init::__internal::PinData for __ThePinData {
         type Datee = Foo;
     }
-    #[allow(dead_code)]
+    #[allow(dead_code, non_snake_case)]
     struct __Unpin<'__pin> {
         __phantom_pin: ::core::marker::PhantomData<fn(&'__pin ()) -> &'__pin ()>,
         __phantom: ::core::marker::PhantomData<fn(Foo) -> Foo>,