feat(cordyceps): add core::iter trait impls for List

cordyceps/src/list.rs

@@ -6,7 +6,7 @@ use super::Linked;
 use crate::util::FmtOption;
 use core::{
     cell::UnsafeCell,
-    fmt,
+    fmt, iter,
     marker::PhantomPinned,
     mem,
     pin::Pin,
@@ -746,6 +746,31 @@ impl<T: Linked<Links<T>> + ?Sized> List<T> {
     }
 }
 
+impl<T> iter::Extend<T::Handle> for List<T>
+where
+    T: Linked<Links<T>> + ?Sized,
+{
+    fn extend<I: IntoIterator<Item = T::Handle>>(&mut self, iter: I) {
+        for item in iter {
+            self.push_back(item);
+        }
+    }
+
+    // TODO(eliza): when `Extend::extend_one` becomes stable, implement that
+    // as well, so that we can just call `push_back` without looping.
+}
+
+impl<T> iter::FromIterator<T::Handle> for List<T>
+where
+    T: Linked<Links<T>> + ?Sized,
+{
+    fn from_iter<I: IntoIterator<Item = T::Handle>>(iter: I) -> Self {
+        let mut list = Self::new();
+        list.extend(iter);
+        list
+    }
+}
+
 unsafe impl<T: Linked<Links<T>> + ?Sized> Send for List<T> where T: Send {}
 unsafe impl<T: Linked<Links<T>> + ?Sized> Sync for List<T> where T: Sync {}
 

cordyceps/src/list/tests.rs

@@ -70,9 +70,15 @@ fn push_all<'a>(
     list: &mut List<Entry<'a>>,
     entries: impl IntoIterator<Item = &'a Pin<Box<Entry<'a>>>>,
 ) {
-    for entry in entries.into_iter() {
-        list.push_back(entry.as_ref());
-    }
+    list.extend(entries.into_iter().map(Pin::as_ref))
+}
+
+fn list_from_iter<'a>(
+    entries: impl IntoIterator<Item = &'a Pin<Box<Entry<'a>>>>,
+) -> List<Entry<'a>> {
+    let mut list = List::new();
+    push_all(&mut list, entries);
+    list
 }
 
 macro_rules! assert_clean {
@@ -230,10 +236,7 @@ fn push_pop_push_pop() {
 #[test]
 fn double_ended_iter() {
     let entries = [entry(1), entry(2), entry(3)];
-
-    let mut list = List::new();
-
-    push_all(&mut list, &entries);
+    let list = list_from_iter(&entries);
 
     let head_to_tail = list.iter().map(|entry| entry.val).collect::<Vec<_>>();
     assert_eq!(&head_to_tail, &[1, 2, 3]);
@@ -250,9 +253,7 @@ fn double_ended_iter() {
 fn double_ended_iter_empties() {
     let entries = [entry(1), entry(2), entry(3), entry(4)];
 
-    let mut list = List::new();
-
-    push_all(&mut list, &entries);
+    let list = list_from_iter(&entries);
 
     let mut iter = list.iter();
 
@@ -269,10 +270,7 @@ fn double_ended_iter_empties() {
 #[test]
 fn drain_filter() {
     let entries = [entry(1), entry(2), entry(3), entry(4)];
-
-    let mut list = List::new();
-
-    push_all(&mut list, &entries);
+    let mut list = list_from_iter(&entries);
 
     {
         // Create a scope so that the mutable borrow on the list is released

cordyceps/src/list/tests/cursor.rs

@@ -8,9 +8,8 @@ fn move_peek() {
     let _ = super::trace_init();
 
     let entries = [entry(1), entry(2), entry(3), entry(4), entry(5), entry(6)];
+    let mut list = list_from_iter(&entries);
 
-    let mut list = List::new();
-    push_all(&mut list, &entries);
     let mut cursor = list.cursor_front_mut();
     assert_eq!(val(cursor.current()), Some(1));
     assert_eq!(val(cursor.peek_next()), Some(2));
@@ -111,8 +110,7 @@ fn cursor_mut_insert() {
     let nine = entry(9);
     let ten = entry(10);
 
-    let mut list = List::<Entry<'_>>::new();
-    push_all(&mut list, &entries);
+    let mut list = list_from_iter(&entries);
 
     let mut cursor = list.cursor_front_mut();
     cursor.insert_before(seven.as_ref());

cordyceps/src/list/tests/remove_by_addr.rs

@@ -9,9 +9,10 @@ fn first() {
 
     unsafe {
         // Remove first
-        let mut list = List::new();
+        let mut list = [a.as_ref(), b.as_ref(), c.as_ref()]
+            .into_iter()
+            .collect::<List<_>>();
 
-        push_all(&mut list, vec![&a, &b, &c]);
         assert!(list.remove(ptr(&a)).is_some());
         assert_clean!(a);
         list.assert_valid();
@@ -41,9 +42,7 @@ fn first() {
 
     unsafe {
         // Remove first of two
-        let mut list = List::new();
-
-        push_all(&mut list, vec![&a, &b]);
+        let mut list = [a.as_ref(), b.as_ref()].into_iter().collect::<List<_>>();
 
         assert!(list.remove(ptr(&a)).is_some());
         assert_clean!(a);
@@ -73,9 +72,9 @@ fn middle() {
     let c = entry(31);
 
     unsafe {
-        let mut list = List::new();
-
-        push_all(&mut list, vec![&a, &b, &c]);
+        let mut list = [a.as_ref(), b.as_ref(), c.as_ref()]
+            .into_iter()
+            .collect::<List<_>>();
 
         assert!(list.remove(ptr(&a)).is_some());
         assert_clean!(a);
@@ -91,9 +90,9 @@ fn middle() {
     }
 
     unsafe {
-        let mut list = List::new();
-
-        push_all(&mut list, vec![&a, &b, &c]);
+        let mut list = [a.as_ref(), b.as_ref(), c.as_ref()]
+            .into_iter()
+            .collect::<List<_>>();
 
         assert!(list.remove(ptr(&b)).is_some());
         assert_clean!(b);
@@ -118,9 +117,9 @@ fn last_middle() {
     unsafe {
         // Remove last
         // Remove middle
-        let mut list = List::new();
-
-        push_all(&mut list, vec![&a, &b, &c]);
+        let mut list = [a.as_ref(), b.as_ref(), c.as_ref()]
+            .into_iter()
+            .collect::<List<_>>();
 
         assert!(list.remove(ptr(&c)).is_some());
         assert_clean!(c);
@@ -143,9 +142,7 @@ fn last() {
 
     unsafe {
         // Remove last item
-        let mut list = List::new();
-
-        push_all(&mut list, Some(&a));
+        let mut list = [a.as_ref()].into_iter().collect::<List<_>>();
 
         assert!(list.remove(ptr(&a)).is_some());
         assert_clean!(a);
@@ -159,9 +156,7 @@ fn last() {
 
     unsafe {
         // Remove last of two
-        let mut list = List::new();
-
-        push_all(&mut list, vec![&a, &b]);
+        let mut list = [a.as_ref(), b.as_ref()].into_iter().collect::<List<_>>();
 
         assert!(list.remove(ptr(&b)).is_some());
         assert_clean!(b);