Forbid custom Unpin/Drop impl if trait has Pin<&mut self> receiver

If a user creates their own Unpin or Drop implementation, trait implementations with `Pin<&mut self>` receiver can cause unsoundness. This was not a problem in #[auto_enum] attribute where enums are anonymized, but it becomes a problem when users have access to enums (i.e., when using #[enum_derive]). So, we ensure safety here by an Unpin implementation that implements Unpin only if all fields are Unpin (this also forbids custom Unpin implementation), and a hack that forbids custom Drop implementation. (Both are what pin-project does by default.) The repr(packed) check is not needed since repr(packed) is not available on enum.
taiki-e · Dec 10, 2022 · cf9d9fa · cf9d9fa
1 parent 36acf01
commit cf9d9fa
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Showing 31 changed files with 258 additions and 60 deletions.
diff --git a/src/derive/core/convert.rs b/src/derive/core/convert.rs
@@ -3,7 +3,7 @@ pub(crate) mod as_ref {
 
     pub(crate) const NAME: &[&str] = &["AsRef"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
         Ok(derive_trait(data, parse_quote!(::core::convert::AsRef), None, parse_quote! {
             trait AsRef<__T: ?Sized> {
                 #[inline]
@@ -18,7 +18,7 @@ pub(crate) mod as_mut {
 
     pub(crate) const NAME: &[&str] = &["AsMut"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
         Ok(derive_trait(data, parse_quote!(::core::convert::AsMut), None, parse_quote! {
             trait AsMut<__T: ?Sized> {
                 #[inline]

diff --git a/src/derive/core/fmt.rs b/src/derive/core/fmt.rs
@@ -5,7 +5,7 @@ macro_rules! derive_fmt {
 
             pub(crate) const NAME: &[&str] = &[$($name),*];
 
-            pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+            pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
                 Ok(derive_trait(data, parse_quote!(::core::fmt::$Trait), None, parse_quote! {
                     trait $Trait {
                         #[inline]
@@ -40,7 +40,7 @@ pub(crate) mod write {
 
     pub(crate) const NAME: &[&str] = &["fmt::Write"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
         Ok(derive_trait(data, parse_quote!(::core::fmt::Write), None, parse_quote! {
             trait Write {
                 #[inline]

diff --git a/src/derive/core/future.rs b/src/derive/core/future.rs
@@ -2,7 +2,8 @@ use crate::derive::*;
 
 pub(crate) const NAME: &[&str] = &["Future"];
 
-pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+pub(crate) fn derive(cx: &Context, data: &Data) -> Result<TokenStream> {
+    cx.needs_pin_projection();
     Ok(derive_trait(data, parse_quote!(::core::future::Future), None, parse_quote! {
         trait Future {
             type Output;

diff --git a/src/derive/core/iter.rs b/src/derive/core/iter.rs
@@ -3,7 +3,7 @@ pub(crate) mod iterator {
 
     pub(crate) const NAME: &[&str] = &["Iterator"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
         // TODO: When `try_trait` stabilized, add `try_fold` and remove `fold`, `find` etc. conditionally.
 
         // It is equally efficient if `try_fold` can be used.
@@ -47,7 +47,7 @@ pub(crate) mod double_ended_iterator {
 
     pub(crate) const NAME: &[&str] = &["DoubleEndedIterator"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
         // TODO: When `try_trait` stabilized, add `try_rfold` and remove `rfold` and `rfind` conditionally.
 
         // It is equally efficient if `try_rfold` can be used.
@@ -82,7 +82,7 @@ pub(crate) mod exact_size_iterator {
 
     pub(crate) const NAME: &[&str] = &["ExactSizeIterator"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
         // TODO: When `exact_size_is_empty` stabilized, add `is_empty` conditionally.
 
         Ok(derive_trait(
@@ -104,7 +104,7 @@ pub(crate) mod fused_iterator {
 
     pub(crate) const NAME: &[&str] = &["FusedIterator"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
         Ok(derive_trait(
             data,
             parse_quote!(::core::iter::FusedIterator),
@@ -122,7 +122,7 @@ pub(crate) mod trusted_len {
 
     pub(crate) const NAME: &[&str] = &["TrustedLen"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
         Ok(derive_trait(
             data,
             parse_quote!(::core::iter::TrustedLen),
@@ -139,7 +139,7 @@ pub(crate) mod extend {
 
     pub(crate) const NAME: &[&str] = &["Extend"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
         Ok(derive_trait(data, parse_quote!(::core::iter::Extend), None, parse_quote! {
             trait Extend<__A> {
                 #[inline]

diff --git a/src/derive/core/ops.rs b/src/derive/core/ops.rs
@@ -4,7 +4,7 @@ pub(crate) mod deref {
 
     pub(crate) const NAME: &[&str] = &["Deref"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
         Ok(derive_trait(data, parse_quote!(::core::ops::Deref), None, parse_quote! {
             trait Deref {
                 type Target;
@@ -21,7 +21,7 @@ pub(crate) mod deref_mut {
 
     pub(crate) const NAME: &[&str] = &["DerefMut"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
         Ok(derive_trait(
             data,
             parse_quote!(::core::ops::DerefMut),
@@ -42,7 +42,7 @@ pub(crate) mod index {
 
     pub(crate) const NAME: &[&str] = &["Index"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
         Ok(derive_trait(data, parse_quote!(::core::ops::Index), None, parse_quote! {
             trait Index<__Idx> {
                 type Output;
@@ -59,7 +59,7 @@ pub(crate) mod index_mut {
 
     pub(crate) const NAME: &[&str] = &["IndexMut"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
         Ok(derive_trait(
             data,
             parse_quote!(::core::ops::IndexMut),
@@ -80,7 +80,7 @@ pub(crate) mod range_bounds {
 
     pub(crate) const NAME: &[&str] = &["RangeBounds"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
         Ok(derive_trait(data, parse_quote!(::core::ops::RangeBounds), None, parse_quote! {
             trait RangeBounds<__T: ?Sized> {
                 #[inline]
@@ -98,7 +98,8 @@ pub(crate) mod generator {
 
     pub(crate) const NAME: &[&str] = &["Generator"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(cx: &Context, data: &Data) -> Result<TokenStream> {
+        cx.needs_pin_projection();
         Ok(derive_trait(data, parse_quote!(::core::ops::Generator), None, parse_quote! {
             trait Generator<R> {
                 type Yield;
@@ -122,7 +123,7 @@ pub(crate) mod fn_ {
 
     pub(crate) const NAME: &[&str] = &["Fn"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
         let trait_path = quote!(::core::ops::Fn);
         let trait_ = quote!(#trait_path(__T) -> __U);
         let fst = data.field_types().next();
@@ -155,7 +156,7 @@ pub(crate) mod fn_mut {
 
     pub(crate) const NAME: &[&str] = &["FnMut"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
         let trait_path = quote!(::core::ops::FnMut);
         let trait_ = quote!(#trait_path(__T) -> __U);
         let fst = data.field_types().next();
@@ -188,7 +189,7 @@ pub(crate) mod fn_once {
 
     pub(crate) const NAME: &[&str] = &["FnOnce"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
         let trait_path = quote!(::core::ops::FnOnce);
         let trait_ = quote!(#trait_path(__T) -> __U);
         let fst = data.field_types().next();

diff --git a/src/derive/external/futures01.rs b/src/derive/external/futures01.rs
@@ -3,7 +3,7 @@ pub(crate) mod future {
 
     pub(crate) const NAME: &[&str] = &["futures01::Future"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
         Ok(derive_trait(data, parse_quote!(::futures::future::Future), None, parse_quote! {
             trait Future {
                 type Item;
@@ -20,7 +20,7 @@ pub(crate) mod stream {
 
     pub(crate) const NAME: &[&str] = &["futures01::Stream"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
         Ok(derive_trait(data, parse_quote!(::futures::stream::Stream), None, parse_quote! {
             trait Stream {
                 type Item;
@@ -39,7 +39,7 @@ pub(crate) mod sink {
 
     pub(crate) const NAME: &[&str] = &["futures01::Sink"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
         Ok(derive_trait(data, parse_quote!(::futures::sink::Sink), None, parse_quote! {
             trait Sink {
                 type SinkItem;

diff --git a/src/derive/external/futures03.rs b/src/derive/external/futures03.rs
@@ -3,7 +3,8 @@ pub(crate) mod async_buf_read {
 
     pub(crate) const NAME: &[&str] = &["futures03::AsyncBufRead"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(cx: &Context, data: &Data) -> Result<TokenStream> {
+        cx.needs_pin_projection();
         Ok(derive_trait(data, parse_quote!(::futures::io::AsyncBufRead), None, parse_quote! {
             trait AsyncBufRead {
                 #[inline]
@@ -23,7 +24,8 @@ pub(crate) mod async_read {
 
     pub(crate) const NAME: &[&str] = &["futures03::AsyncRead"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(cx: &Context, data: &Data) -> Result<TokenStream> {
+        cx.needs_pin_projection();
         Ok(derive_trait(data, parse_quote!(::futures::io::AsyncRead), None, parse_quote! {
             trait AsyncRead {
                 #[inline]
@@ -48,7 +50,8 @@ pub(crate) mod async_seek {
 
     pub(crate) const NAME: &[&str] = &["futures03::AsyncSeek"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(cx: &Context, data: &Data) -> Result<TokenStream> {
+        cx.needs_pin_projection();
         Ok(derive_trait(data, parse_quote!(::futures::io::AsyncSeek), None, parse_quote! {
             trait AsyncSeek {
                 #[inline]
@@ -67,7 +70,8 @@ pub(crate) mod async_write {
 
     pub(crate) const NAME: &[&str] = &["futures03::AsyncWrite"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(cx: &Context, data: &Data) -> Result<TokenStream> {
+        cx.needs_pin_projection();
         Ok(derive_trait(data, parse_quote!(::futures::io::AsyncWrite), None, parse_quote! {
             trait AsyncWrite {
                 #[inline]
@@ -102,7 +106,8 @@ pub(crate) mod sink {
 
     pub(crate) const NAME: &[&str] = &["futures03::Sink"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(cx: &Context, data: &Data) -> Result<TokenStream> {
+        cx.needs_pin_projection();
         Ok(derive_trait(data, parse_quote!(::futures::sink::Sink), None, parse_quote! {
             trait Sink<Item> {
                 type Error;
@@ -136,7 +141,8 @@ pub(crate) mod stream {
 
     pub(crate) const NAME: &[&str] = &["futures03::Stream"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(cx: &Context, data: &Data) -> Result<TokenStream> {
+        cx.needs_pin_projection();
         Ok(derive_trait(data, parse_quote!(::futures::stream::Stream), None, parse_quote! {
             trait Stream {
                 type Item;

diff --git a/src/derive/external/rayon.rs b/src/derive/external/rayon.rs
@@ -3,7 +3,7 @@ pub(crate) mod par_iter {
 
     pub(crate) const NAME: &[&str] = &["rayon::ParallelIterator"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
         Ok(derive_trait(data, parse_quote!(::rayon::iter::ParallelIterator), None, parse_quote! {
             trait ParallelIterator {
                 type Item;
@@ -23,7 +23,7 @@ pub(crate) mod indexed_par_iter {
 
     pub(crate) const NAME: &[&str] = &["rayon::IndexedParallelIterator"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
         Ok(derive_trait(
             data,
             parse_quote!(::rayon::iter::IndexedParallelIterator),
@@ -51,7 +51,7 @@ pub(crate) mod par_extend {
 
     pub(crate) const NAME: &[&str] = &["rayon::ParallelExtend"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
         Ok(derive_trait(data, parse_quote!(::rayon::iter::ParallelExtend), None, parse_quote! {
             trait ParallelExtend<__T: Send> {
                 #[inline]

diff --git a/src/derive/external/serde.rs b/src/derive/external/serde.rs
@@ -3,7 +3,7 @@ pub(crate) mod serialize {
 
     pub(crate) const NAME: &[&str] = &["serde::Serialize"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
         Ok(derive_trait(data, parse_quote!(::serde::ser::Serialize), None, parse_quote! {
             trait Serialize {
                 #[inline]

diff --git a/src/derive/external/tokio01.rs b/src/derive/external/tokio01.rs
@@ -3,7 +3,7 @@ pub(crate) mod async_read {
 
     pub(crate) const NAME: &[&str] = &["tokio01::AsyncRead"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
         Ok(derive_trait(data, parse_quote!(::tokio::io::AsyncRead), None, parse_quote! {
             trait AsyncRead: ::std::io::Read {
                 unsafe fn prepare_uninitialized_buffer(&self, buf: &mut [u8]) -> bool;
@@ -29,7 +29,7 @@ pub(crate) mod async_write {
 
     pub(crate) const NAME: &[&str] = &["tokio01::AsyncWrite"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(_cx: &Context, data: &Data) -> Result<TokenStream> {
         Ok(derive_trait(data, parse_quote!(::tokio::io::AsyncWrite), None, parse_quote! {
             trait AsyncWrite: ::std::io::Write {
                 fn poll_write(

diff --git a/src/derive/external/tokio02.rs b/src/derive/external/tokio02.rs
@@ -3,7 +3,8 @@ pub(crate) mod async_buf_read {
 
     pub(crate) const NAME: &[&str] = &["tokio02::AsyncBufRead"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(cx: &Context, data: &Data) -> Result<TokenStream> {
+        cx.needs_pin_projection();
         Ok(derive_trait(data, parse_quote!(::tokio::io::AsyncBufRead), None, parse_quote! {
             trait AsyncBufRead {
                 fn poll_fill_buf<'__a>(
@@ -21,7 +22,8 @@ pub(crate) mod async_read {
 
     pub(crate) const NAME: &[&str] = &["tokio02::AsyncRead"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(cx: &Context, data: &Data) -> Result<TokenStream> {
+        cx.needs_pin_projection();
         Ok(derive_trait(data, parse_quote!(::tokio::io::AsyncRead), None, parse_quote! {
             trait AsyncRead {
                 unsafe fn prepare_uninitialized_buffer(
@@ -51,7 +53,8 @@ pub(crate) mod async_seek {
 
     pub(crate) const NAME: &[&str] = &["tokio02::AsyncSeek"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(cx: &Context, data: &Data) -> Result<TokenStream> {
+        cx.needs_pin_projection();
         Ok(derive_trait(data, parse_quote!(::tokio::io::AsyncSeek), None, parse_quote! {
             trait AsyncSeek {
                 fn start_seek(
@@ -73,7 +76,8 @@ pub(crate) mod async_write {
 
     pub(crate) const NAME: &[&str] = &["tokio02::AsyncWrite"];
 
-    pub(crate) fn derive(data: &Data) -> Result<TokenStream> {
+    pub(crate) fn derive(cx: &Context, data: &Data) -> Result<TokenStream> {
+        cx.needs_pin_projection();
         Ok(derive_trait(data, parse_quote!(::tokio::io::AsyncWrite), None, parse_quote! {
             trait AsyncWrite {
                 fn poll_write(