1 files changed, 361 insertions, 0 deletions
diff --git a/vendor/rowan/src/green/node.rs b/vendor/rowan/src/green/node.rs
new file mode 100644
index 000000000..e94dc01cf
--- /dev/null
+++ b/vendor/rowan/src/green/node.rs
@@ -0,0 +1,361 @@
+use std::{
+    borrow::{Borrow, Cow},
+    fmt,
+    iter::{self, FusedIterator},
+    mem::{self, ManuallyDrop},
+    ops, ptr, slice,
+};
+
+use countme::Count;
+
+use crate::{
+    arc::{Arc, HeaderSlice, ThinArc},
+    green::{GreenElement, GreenElementRef, SyntaxKind},
+    utility_types::static_assert,
+    GreenToken, NodeOrToken, TextRange, TextSize,
+};
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub(super) struct GreenNodeHead {
+    kind: SyntaxKind,
+    text_len: TextSize,
+    _c: Count<GreenNode>,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub(crate) enum GreenChild {
+    Node { rel_offset: TextSize, node: GreenNode },
+    Token { rel_offset: TextSize, token: GreenToken },
+}
+#[cfg(target_pointer_width = "64")]
+static_assert!(mem::size_of::<GreenChild>() == mem::size_of::<usize>() * 2);
+
+type Repr = HeaderSlice<GreenNodeHead, [GreenChild]>;
+type ReprThin = HeaderSlice<GreenNodeHead, [GreenChild; 0]>;
+#[repr(transparent)]
+pub struct GreenNodeData {
+    data: ReprThin,
+}
+
+impl PartialEq for GreenNodeData {
+    fn eq(&self, other: &Self) -> bool {
+        self.header() == other.header() && self.slice() == other.slice()
+    }
+}
+
+/// Internal node in the immutable tree.
+/// It has other nodes and tokens as children.
+#[derive(Clone, PartialEq, Eq, Hash)]
+#[repr(transparent)]
+pub struct GreenNode {
+    ptr: ThinArc<GreenNodeHead, GreenChild>,
+}
+
+impl ToOwned for GreenNodeData {
+    type Owned = GreenNode;
+
+    #[inline]
+    fn to_owned(&self) -> GreenNode {
+        unsafe {
+            let green = GreenNode::from_raw(ptr::NonNull::from(self));
+            let green = ManuallyDrop::new(green);
+            GreenNode::clone(&green)
+        }
+    }
+}
+
+impl Borrow<GreenNodeData> for GreenNode {
+    #[inline]
+    fn borrow(&self) -> &GreenNodeData {
+        &*self
+    }
+}
+
+impl From<Cow<'_, GreenNodeData>> for GreenNode {
+    #[inline]
+    fn from(cow: Cow<'_, GreenNodeData>) -> Self {
+        cow.into_owned()
+    }
+}
+
+impl fmt::Debug for GreenNodeData {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_struct("GreenNode")
+            .field("kind", &self.kind())
+            .field("text_len", &self.text_len())
+            .field("n_children", &self.children().len())
+            .finish()
+    }
+}
+
+impl fmt::Debug for GreenNode {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let data: &GreenNodeData = &*self;
+        fmt::Debug::fmt(data, f)
+    }
+}
+
+impl fmt::Display for GreenNode {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let data: &GreenNodeData = &*self;
+        fmt::Display::fmt(data, f)
+    }
+}
+
+impl fmt::Display for GreenNodeData {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        for child in self.children() {
+            write!(f, "{}", child)?;
+        }
+        Ok(())
+    }
+}
+
+impl GreenNodeData {
+    #[inline]
+    fn header(&self) -> &GreenNodeHead {
+        &self.data.header
+    }
+
+    #[inline]
+    fn slice(&self) -> &[GreenChild] {
+        self.data.slice()
+    }
+
+    /// Kind of this node.
+    #[inline]
+    pub fn kind(&self) -> SyntaxKind {
+        self.header().kind
+    }
+
+    /// Returns the length of the text covered by this node.
+    #[inline]
+    pub fn text_len(&self) -> TextSize {
+        self.header().text_len
+    }
+
+    /// Children of this node.
+    #[inline]
+    pub fn children(&self) -> Children<'_> {
+        Children { raw: self.slice().iter() }
+    }
+
+    pub(crate) fn child_at_range(
+        &self,
+        rel_range: TextRange,
+    ) -> Option<(usize, TextSize, GreenElementRef<'_>)> {
+        let idx = self
+            .slice()
+            .binary_search_by(|it| {
+                let child_range = it.rel_range();
+                TextRange::ordering(child_range, rel_range)
+            })
+            // XXX: this handles empty ranges
+            .unwrap_or_else(|it| it.saturating_sub(1));
+        let child = &self.slice().get(idx).filter(|it| it.rel_range().contains_range(rel_range))?;
+        Some((idx, child.rel_offset(), child.as_ref()))
+    }
+
+    #[must_use]
+    pub fn replace_child(&self, index: usize, new_child: GreenElement) -> GreenNode {
+        let mut replacement = Some(new_child);
+        let children = self.children().enumerate().map(|(i, child)| {
+            if i == index {
+                replacement.take().unwrap()
+            } else {
+                child.to_owned()
+            }
+        });
+        GreenNode::new(self.kind(), children)
+    }
+    #[must_use]
+    pub fn insert_child(&self, index: usize, new_child: GreenElement) -> GreenNode {
+        // https://github.com/rust-lang/rust/issues/34433
+        self.splice_children(index..index, iter::once(new_child))
+    }
+    #[must_use]
+    pub fn remove_child(&self, index: usize) -> GreenNode {
+        self.splice_children(index..=index, iter::empty())
+    }
+    #[must_use]
+    pub fn splice_children<R, I>(&self, range: R, replace_with: I) -> GreenNode
+    where
+        R: ops::RangeBounds<usize>,
+        I: IntoIterator<Item = GreenElement>,
+    {
+        let mut children: Vec<_> = self.children().map(|it| it.to_owned()).collect();
+        children.splice(range, replace_with);
+        GreenNode::new(self.kind(), children)
+    }
+}
+
+impl ops::Deref for GreenNode {
+    type Target = GreenNodeData;
+
+    #[inline]
+    fn deref(&self) -> &GreenNodeData {
+        unsafe {
+            let repr: &Repr = &self.ptr;
+            let repr: &ReprThin = &*(repr as *const Repr as *const ReprThin);
+            mem::transmute::<&ReprThin, &GreenNodeData>(repr)
+        }
+    }
+}
+
+impl GreenNode {
+    /// Creates new Node.
+    #[inline]
+    pub fn new<I>(kind: SyntaxKind, children: I) -> GreenNode
+    where
+        I: IntoIterator<Item = GreenElement>,
+        I::IntoIter: ExactSizeIterator,
+    {
+        let mut text_len: TextSize = 0.into();
+        let children = children.into_iter().map(|el| {
+            let rel_offset = text_len;
+            text_len += el.text_len();
+            match el {
+                NodeOrToken::Node(node) => GreenChild::Node { rel_offset, node },
+                NodeOrToken::Token(token) => GreenChild::Token { rel_offset, token },
+            }
+        });
+
+        let data = ThinArc::from_header_and_iter(
+            GreenNodeHead { kind, text_len: 0.into(), _c: Count::new() },
+            children,
+        );
+
+        // XXX: fixup `text_len` after construction, because we can't iterate
+        // `children` twice.
+        let data = {
+            let mut data = Arc::from_thin(data);
+            Arc::get_mut(&mut data).unwrap().header.text_len = text_len;
+            Arc::into_thin(data)
+        };
+
+        GreenNode { ptr: data }
+    }
+
+    #[inline]
+    pub(crate) fn into_raw(this: GreenNode) -> ptr::NonNull<GreenNodeData> {
+        let green = ManuallyDrop::new(this);
+        let green: &GreenNodeData = &*green;
+        ptr::NonNull::from(&*green)
+    }
+
+    #[inline]
+    pub(crate) unsafe fn from_raw(ptr: ptr::NonNull<GreenNodeData>) -> GreenNode {
+        let arc = Arc::from_raw(&ptr.as_ref().data as *const ReprThin);
+        let arc = mem::transmute::<Arc<ReprThin>, ThinArc<GreenNodeHead, GreenChild>>(arc);
+        GreenNode { ptr: arc }
+    }
+}
+
+impl GreenChild {
+    #[inline]
+    pub(crate) fn as_ref(&self) -> GreenElementRef {
+        match self {
+            GreenChild::Node { node, .. } => NodeOrToken::Node(node),
+            GreenChild::Token { token, .. } => NodeOrToken::Token(token),
+        }
+    }
+    #[inline]
+    pub(crate) fn rel_offset(&self) -> TextSize {
+        match self {
+            GreenChild::Node { rel_offset, .. } | GreenChild::Token { rel_offset, .. } => {
+                *rel_offset
+            }
+        }
+    }
+    #[inline]
+    fn rel_range(&self) -> TextRange {
+        let len = self.as_ref().text_len();
+        TextRange::at(self.rel_offset(), len)
+    }
+}
+
+#[derive(Debug, Clone)]
+pub struct Children<'a> {
+    pub(crate) raw: slice::Iter<'a, GreenChild>,
+}
+
+// NB: forward everything stable that iter::Slice specializes as of Rust 1.39.0
+impl ExactSizeIterator for Children<'_> {
+    #[inline(always)]
+    fn len(&self) -> usize {
+        self.raw.len()
+    }
+}
+
+impl<'a> Iterator for Children<'a> {
+    type Item = GreenElementRef<'a>;
+
+    #[inline]
+    fn next(&mut self) -> Option<GreenElementRef<'a>> {
+        self.raw.next().map(GreenChild::as_ref)
+    }
+
+    #[inline]
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        self.raw.size_hint()
+    }
+
+    #[inline]
+    fn count(self) -> usize
+    where
+        Self: Sized,
+    {
+        self.raw.count()
+    }
+
+    #[inline]
+    fn nth(&mut self, n: usize) -> Option<Self::Item> {
+        self.raw.nth(n).map(GreenChild::as_ref)
+    }
+
+    #[inline]
+    fn last(mut self) -> Option<Self::Item>
+    where
+        Self: Sized,
+    {
+        self.next_back()
+    }
+
+    #[inline]
+    fn fold<Acc, Fold>(mut self, init: Acc, mut f: Fold) -> Acc
+    where
+        Fold: FnMut(Acc, Self::Item) -> Acc,
+    {
+        let mut accum = init;
+        while let Some(x) = self.next() {
+            accum = f(accum, x);
+        }
+        accum
+    }
+}
+
+impl<'a> DoubleEndedIterator for Children<'a> {
+    #[inline]
+    fn next_back(&mut self) -> Option<Self::Item> {
+        self.raw.next_back().map(GreenChild::as_ref)
+    }
+
+    #[inline]
+    fn nth_back(&mut self, n: usize) -> Option<Self::Item> {
+        self.raw.nth_back(n).map(GreenChild::as_ref)
+    }
+
+    #[inline]
+    fn rfold<Acc, Fold>(mut self, init: Acc, mut f: Fold) -> Acc
+    where
+        Fold: FnMut(Acc, Self::Item) -> Acc,
+    {
+        let mut accum = init;
+        while let Some(x) = self.next_back() {
+            accum = f(accum, x);
+        }
+        accum
+    }
+}
+
+impl FusedIterator for Children<'_> {}