feat: support intrusive_adapter! access nested field

.github/workflows/ci.yml

@@ -8,7 +8,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        rust: [1.56.1, stable, beta, nightly]
+        rust: [1.82.0, stable, beta, nightly]
     steps:
     - name: Checkout
       uses: actions/checkout@v2

src/adapter.rs

@@ -98,10 +98,10 @@ pub unsafe trait Adapter {
 /// pointer to the specified field of some container type.
 #[macro_export]
 macro_rules! container_of {
-    ($ptr:expr, $container:path, $field:ident) => {
+    ($ptr:expr, $container:path, $($fields:expr)+) => {
         #[allow(clippy::cast_ptr_alignment)]
         {
-            ($ptr as *const _ as *const u8).sub($crate::offset_of!($container, $field))
+            ($ptr as *const _ as *const u8).sub($crate::offset_of!($container, $($fields)+))
                 as *const $container
         }
     };
@@ -114,7 +114,7 @@ macro_rules! container_of {
 /// The basic syntax to create an adapter is:
 ///
 /// ```rust,ignore
-/// intrusive_adapter!(Adapter = Pointer: Value { link_field: LinkType });
+/// intrusive_adapter!(Adapter = Pointer: Value { link_field => LinkType });
 /// ```
 ///
 /// You can create a new instance of an adapter using the `new` method or the
@@ -128,7 +128,7 @@ macro_rules! container_of {
 /// intrusive_adapter!(
 ///     Adapter<'lifetime, Type, Type2> =
 ///         Pointer: Value {
-///             link_field: LinkType
+///             link_field => LinkType
 ///         }
 ///         where
 ///             Type: Copy,
@@ -150,23 +150,23 @@ macro_rules! container_of {
 ///     link: LinkedListLink,
 ///     link2: RBTreeLink,
 /// }
-/// intrusive_adapter!(MyAdapter = Box<Test>: Test { link: LinkedListLink });
-/// intrusive_adapter!(pub MyAdapter2 = Box<Test>: Test { link2: RBTreeLink });
-/// intrusive_adapter!(pub(crate) MyAdapter3 = Box<Test>: Test { link2: RBTreeLink });
+/// intrusive_adapter!(MyAdapter = Box<Test>: Test { link => LinkedListLink });
+/// intrusive_adapter!(pub MyAdapter2 = Box<Test>: Test { link2 => RBTreeLink });
+/// intrusive_adapter!(pub(crate) MyAdapter3 = Box<Test>: Test { link2 => RBTreeLink });
 ///
 /// pub struct Test2<T>
 ///     where T: Clone + ?Sized
 /// {
 ///     link: LinkedListLink,
 ///     val: T,
 /// }
-/// intrusive_adapter!(MyAdapter4<'a, T> = &'a Test2<T>: Test2<T> { link: LinkedListLink } where T: ?Sized + Clone + 'a);
+/// intrusive_adapter!(MyAdapter4<'a, T> = &'a Test2<T>: Test2<T> { link => LinkedListLink } where T: ?Sized + Clone + 'a);
 /// ```
 #[macro_export]
 macro_rules! intrusive_adapter {
     (@impl
         $(#[$attr:meta])* $vis:vis $name:ident ($($args:tt),*)
-        = $pointer:ty: $value:path { $field:ident: $link:ty } $($where_:tt)*
+        = $pointer:ty: $value:path { $($fields:expr)+ => $link:ty } $($where_:tt)*
     ) => {
         #[allow(explicit_outlives_requirements)]
         $(#[$attr])*
@@ -207,13 +207,13 @@ macro_rules! intrusive_adapter {
 
             #[inline]
             unsafe fn get_value(&self, link: <Self::LinkOps as $crate::LinkOps>::LinkPtr) -> *const <Self::PointerOps as $crate::PointerOps>::Value {
-                $crate::container_of!(link.as_ptr(), $value, $field)
+                $crate::container_of!(link.as_ptr(), $value, $($fields)+)
             }
             #[inline]
             unsafe fn get_link(&self, value: *const <Self::PointerOps as $crate::PointerOps>::Value) -> <Self::LinkOps as $crate::LinkOps>::LinkPtr {
                 // We need to do this instead of just accessing the field directly
                 // to strictly follow the stack borrow rules.
-                let ptr = (value as *const u8).add($crate::offset_of!($value, $field));
+                let ptr = (value as *const u8).add($crate::offset_of!($value, $($fields)+));
                 core::ptr::NonNull::new_unchecked(ptr as *mut _)
             }
             #[inline]
@@ -274,8 +274,17 @@ mod tests {
         link: LinkedListLink,
     }
 
+    struct Wrapper {
+        obj: Obj,
+    }
+
+    intrusive_adapter! {
+        /// Test doc comment
+        ObjAdapter1 = Rc<Obj>: Obj { link => LinkedListLink }
+    }
+
     intrusive_adapter! {
         /// Test doc comment
-        ObjAdapter1 = Rc<Obj>: Obj { link: LinkedListLink }
+        WrapperAdapter1 = Rc<Wrapper>: Wrapper { obj.link => LinkedListLink }
     }
 }

src/key_adapter.rs

@@ -29,14 +29,14 @@ use crate::pointer_ops::PointerOps;
 /// }
 ///
 /// // Adapter which returns a key by value
-/// intrusive_adapter!(MyAdapter = Box<S>: S { link : RBTreeLink });
+/// intrusive_adapter!(MyAdapter = Box<S>: S { link => RBTreeLink });
 /// impl<'a> KeyAdapter<'a> for MyAdapter {
 ///     type Key = u32;
 ///     fn get_key(&self, s: &'a S) -> u32 { s.key }
 /// }
 ///
 /// // Adapter which returns a key by reference
-/// intrusive_adapter!(MyAdapter2 = Box<S>: S { link : RBTreeLink });
+/// intrusive_adapter!(MyAdapter2 = Box<S>: S { link => RBTreeLink });
 /// impl<'a> KeyAdapter<'a> for MyAdapter2 {
 ///     type Key = &'a u32;
 ///     fn get_key(&self, s: &'a S) -> &'a u32 { &s.key }
@@ -51,7 +51,7 @@ use crate::pointer_ops::PointerOps;
 ///
 /// // Adapter which returns a tuple as a key. When used in a RBTree, this will
 /// // keep all elements sorted by `key1` first, then `key2` and finally `key3`.
-/// intrusive_adapter!(MyAdapter3 = Box<U>: U { link : RBTreeLink });
+/// intrusive_adapter!(MyAdapter3 = Box<U>: U { link => RBTreeLink });
 /// impl<'a> KeyAdapter<'a> for MyAdapter3 {
 ///     type Key = (i32, &'a str, f64);
 ///     fn get_key(&self, u: &'a U) -> Self::Key { (u.key1, &u.key2, u.key3) }

src/lib.rs

@@ -33,7 +33,7 @@
 //!
 //! // The adapter describes how an object can be inserted into an intrusive
 //! // collection. This is automatically generated using a macro.
-//! intrusive_adapter!(TestAdapter = Box<Test>: Test { link: LinkedListLink });
+//! intrusive_adapter!(TestAdapter = Box<Test>: Test { link => LinkedListLink });
 //!
 //! // Create a list and some objects
 //! let mut list = LinkedList::new(TestAdapter::new());
@@ -106,10 +106,10 @@
 //!     value: i32,
 //! }
 //!
-//! intrusive_adapter!(MyAdapter = Rc<Test>: Test { link: LinkedListLink });
-//! intrusive_adapter!(MyAdapter2 = Rc<Test>: Test { link2: SinglyLinkedListLink });
-//! intrusive_adapter!(MyAdapter3 = Rc<Test>: Test { link3: XorLinkedListLink });
-//! intrusive_adapter!(MyAdapter4 = Rc<Test>: Test { link4: RBTreeLink });
+//! intrusive_adapter!(MyAdapter = Rc<Test>: Test { link => LinkedListLink });
+//! intrusive_adapter!(MyAdapter2 = Rc<Test>: Test { link2 => SinglyLinkedListLink });
+//! intrusive_adapter!(MyAdapter3 = Rc<Test>: Test { link3 => XorLinkedListLink });
+//! intrusive_adapter!(MyAdapter4 = Rc<Test>: Test { link4 => RBTreeLink });
 //! impl<'a> KeyAdapter<'a> for MyAdapter4 {
 //!     type Key = i32;
 //!     fn get_key(&self, x: &'a Test) -> i32 { x.value }
@@ -158,7 +158,7 @@
 //!     value: i32,
 //! }
 //!
-//! intrusive_adapter!(ElementAdapter = Box<Element>: Element { link: RBTreeLink });
+//! intrusive_adapter!(ElementAdapter = Box<Element>: Element { link => RBTreeLink });
 //! impl<'a> KeyAdapter<'a> for ElementAdapter {
 //!     type Key = i32;
 //!     fn get_key(&self, e: &'a Element) -> i32 { e.value }
@@ -197,7 +197,7 @@
 //! }
 //!
 //! // Note that we use a plain reference as the pointer type for the collection.
-//! intrusive_adapter!(ValueAdapter<'a> = &'a Value: Value { link: LinkedListLink });
+//! intrusive_adapter!(ValueAdapter<'a> = &'a Value: Value { link => LinkedListLink });
 //!
 //! // Create an arena and a list. Note that since stack objects are dropped in
 //! // reverse order, the Arena must be created before the LinkedList. This
@@ -267,7 +267,7 @@
 #![warn(missing_docs)]
 #![warn(rust_2018_idioms)]
 #![no_std]
 #![cfg_attr(feature = "nightly", feature(const_fn_trait_bound))]
 #![allow(
     clippy::declare_interior_mutable_const,
     clippy::collapsible_if,

src/linked_list.rs

@@ -1607,9 +1607,9 @@ mod tests {
             write!(f, "{}", self.value)
         }
     }
-    intrusive_adapter!(ObjAdapter1 = Rc<Obj>: Obj { link1: Link });
-    intrusive_adapter!(ObjAdapter2 = Rc<Obj>: Obj { link2: Link });
-    intrusive_adapter!(UnsafeRefObjAdapter1 = UnsafeRef<Obj>: Obj { link1: Link });
+    intrusive_adapter!(ObjAdapter1 = Rc<Obj>: Obj { link1 => Link });
+    intrusive_adapter!(ObjAdapter2 = Rc<Obj>: Obj { link2 => Link });
+    intrusive_adapter!(UnsafeRefObjAdapter1 = UnsafeRef<Obj>: Obj { link1 => Link });
 
     fn make_rc_obj(value: u32) -> Rc<Obj> {
         Rc::new(make_obj(value))
@@ -2009,7 +2009,7 @@ mod tests {
             link: Link,
             value: &'a T,
         }
-        intrusive_adapter!(ObjAdapter<'a, T> = &'a Obj<'a, T>: Obj<'a, T> {link: Link} where T: 'a);
+        intrusive_adapter!(ObjAdapter<'a, T> = &'a Obj<'a, T>: Obj<'a, T> {link => Link} where T: 'a);
 
         let v = 5;
         let a = Obj {
@@ -2033,7 +2033,7 @@ mod tests {
                 link: Link,
                 value: usize,
             }
-            intrusive_adapter!(ObjAdapter = $ptr<Obj>: Obj { link: Link });
+            intrusive_adapter!(ObjAdapter = $ptr<Obj>: Obj { link => Link });
 
             let a = $ptr::new(Obj {
                 link: Link::new(),

src/rbtree.rs

@@ -2043,7 +2043,7 @@
     /// Panics if the new element is already linked to a different intrusive
     /// collection.
     #[inline]
     pub fn insert<'a>(&'a mut self, val: <A::PointerOps as PointerOps>::Pointer) -> CursorMut<'_, A>
     where
         <A as KeyAdapter<'a>>::Key: Ord,
     {
@@ -2550,7 +2550,7 @@
             write!(f, "{}", self.value)
         }
     }
-    intrusive_adapter!(RcObjAdapter = Rc<Obj>: Obj { link: Link });
+    intrusive_adapter!(RcObjAdapter = Rc<Obj>: Obj { link => Link });
 
     impl<'a> KeyAdapter<'a> for RcObjAdapter {
         type Key = i32;
@@ -2559,7 +2559,7 @@
         }
     }
 
-    intrusive_adapter!(UnsafeRefObjAdapter = UnsafeRef<Obj>: Obj { link: Link });
+    intrusive_adapter!(UnsafeRefObjAdapter = UnsafeRef<Obj>: Obj { link => Link });
 
     impl<'a> KeyAdapter<'a> for UnsafeRefObjAdapter {
         type Key = i32;
@@ -3291,7 +3291,7 @@
             link: Link,
             value: &'a T,
         }
-        intrusive_adapter!(RcObjAdapter<'a, T> = &'a Obj<'a, T>: Obj<'a, T> {link: Link} where T: 'a);
+        intrusive_adapter!(RcObjAdapter<'a, T> = &'a Obj<'a, T>: Obj<'a, T> {link => Link} where T: 'a);
         impl<'a, 'b, T: 'a + 'b> KeyAdapter<'a> for RcObjAdapter<'b, T> {
             type Key = &'a T;
             fn get_key(&self, value: &'a Obj<'b, T>) -> &'a T {
@@ -3321,7 +3321,7 @@
                 link: Link,
                 value: usize,
             }
-            intrusive_adapter!(RcObjAdapter = $ptr<Obj>: Obj { link: Link });
+            intrusive_adapter!(RcObjAdapter = $ptr<Obj>: Obj { link => Link });
             impl<'a> KeyAdapter<'a> for RcObjAdapter {
                 type Key = usize;
                 fn get_key(&self, value: &'a Obj) -> usize {

src/singly_linked_list.rs

@@ -1299,9 +1299,9 @@ mod tests {
             write!(f, "{}", self.value)
         }
     }
-    intrusive_adapter!(RcObjAdapter1 = Rc<Obj>: Obj { link1: Link });
-    intrusive_adapter!(RcObjAdapter2 = Rc<Obj>: Obj { link2: Link });
-    intrusive_adapter!(UnsafeRefObjAdapter1 = UnsafeRef<Obj>: Obj { link1: Link });
+    intrusive_adapter!(RcObjAdapter1 = Rc<Obj>: Obj { link1 => Link });
+    intrusive_adapter!(RcObjAdapter2 = Rc<Obj>: Obj { link2 => Link });
+    intrusive_adapter!(UnsafeRefObjAdapter1 = UnsafeRef<Obj>: Obj { link1 => Link });
 
     fn make_rc_obj(value: u32) -> Rc<Obj> {
         Rc::new(make_obj(value))
@@ -1653,7 +1653,7 @@ mod tests {
             link: Link,
             value: &'a T,
         }
-        intrusive_adapter!(ObjAdapter<'a, T> = &'a Obj<'a, T>: Obj<'a, T> {link: Link} where T: 'a);
+        intrusive_adapter!(ObjAdapter<'a, T> = &'a Obj<'a, T>: Obj<'a, T> {link => Link} where T: 'a);
 
         let v = 5;
         let a = Obj {
@@ -1677,7 +1677,7 @@ mod tests {
                 link: Link,
                 value: usize,
             }
-            intrusive_adapter!(ObjAdapter = $ptr<Obj>: Obj { link: Link });
+            intrusive_adapter!(ObjAdapter = $ptr<Obj>: Obj { link => Link });
 
             let a = $ptr::new(Obj {
                 link: Link::new(),

src/xor_linked_list.rs

@@ -1790,9 +1790,9 @@ mod tests {
             write!(f, "{}", self.value)
         }
     }
-    intrusive_adapter!(RcObjAdapter1 = Rc<Obj>: Obj { link1: Link });
-    intrusive_adapter!(RcObjAdapter2 = Rc<Obj>: Obj { link2: Link });
-    intrusive_adapter!(UnsafeRefObjAdapter1 = UnsafeRef<Obj>: Obj { link1: Link });
+    intrusive_adapter!(RcObjAdapter1 = Rc<Obj>: Obj { link1 => Link });
+    intrusive_adapter!(RcObjAdapter2 = Rc<Obj>: Obj { link2 => Link });
+    intrusive_adapter!(UnsafeRefObjAdapter1 = UnsafeRef<Obj>: Obj { link1 => Link });
 
     fn make_rc_obj(value: u32) -> Rc<Obj> {
         Rc::new(make_obj(value))
@@ -2253,7 +2253,7 @@ mod tests {
             link: Link,
             value: &'a T,
         }
-        intrusive_adapter!(ObjAdapter<'a, T> = &'a Obj<'a, T>: Obj<'a, T> {link: Link} where T: 'a);
+        intrusive_adapter!(ObjAdapter<'a, T> = &'a Obj<'a, T>: Obj<'a, T> {link => Link} where T: 'a);
 
         let v = 5;
         let a = Obj {
@@ -2281,7 +2281,7 @@ mod tests {
                 self.value.set(val + 1);
             }
         }
-        intrusive_adapter!(ObjAdapter<'a> = Box<Obj<'a>>: Obj<'a> {link: Link});
+        intrusive_adapter!(ObjAdapter<'a> = Box<Obj<'a>>: Obj<'a> {link => Link});
 
         let v = Cell::new(0);
         let obj = Obj {
@@ -2314,7 +2314,7 @@ mod tests {
                 link: Link,
                 value: usize,
             }
-            intrusive_adapter!(ObjAdapter = $ptr<Obj>: Obj { link: Link });
+            intrusive_adapter!(ObjAdapter = $ptr<Obj>: Obj { link => Link });
 
             let a = $ptr::new(Obj {
                 link: Link::new(),