1 files changed, 223 insertions, 0 deletions

diff --git a/crates/ra_syntax/src/syntax_node.rs b/crates/ra_syntax/src/syntax_node.rs
new file mode 100644
index 000000000..ed48739f8
--- /dev/null
+++ b/crates/ra_syntax/src/syntax_node.rs
@@ -0,0 +1,223 @@
+mod builder;
+pub mod syntax_error;
+mod syntax_text;
+
+use std::{fmt, borrow::Borrow};
+
+use self::syntax_text::SyntaxText;
+use crate::{SmolStr, SyntaxKind, TextRange};
+use rowan::{Types, TransparentNewType};
+
+pub(crate) use self::builder::GreenBuilder;
+pub use self::syntax_error::{SyntaxError, SyntaxErrorKind, Location};
+pub use rowan::WalkEvent;
+
+#[derive(Debug, Clone, Copy)]
+pub enum RaTypes {}
+impl Types for RaTypes {
+    type Kind = SyntaxKind;
+    type RootData = Vec<SyntaxError>;
+}
+
+pub type GreenNode = rowan::GreenNode<RaTypes>;
+
+#[derive(PartialEq, Eq, Hash)]
+pub struct TreeArc<T: TransparentNewType<Repr = rowan::SyntaxNode<RaTypes>>>(
+    pub(crate) rowan::TreeArc<RaTypes, T>,
+);
+
+impl<T: TransparentNewType<Repr = rowan::SyntaxNode<RaTypes>>> Borrow<T> for TreeArc<T> {
+    fn borrow(&self) -> &T {
+        &*self
+    }
+}
+
+impl<T> TreeArc<T>
+where
+    T: TransparentNewType<Repr = rowan::SyntaxNode<RaTypes>>,
+{
+    pub(crate) fn cast<U>(this: TreeArc<T>) -> TreeArc<U>
+    where
+        U: TransparentNewType<Repr = rowan::SyntaxNode<RaTypes>>,
+    {
+        TreeArc(rowan::TreeArc::cast(this.0))
+    }
+}
+
+impl<T> std::ops::Deref for TreeArc<T>
+where
+    T: TransparentNewType<Repr = rowan::SyntaxNode<RaTypes>>,
+{
+    type Target = T;
+    fn deref(&self) -> &T {
+        self.0.deref()
+    }
+}
+
+impl<T> PartialEq<T> for TreeArc<T>
+where
+    T: TransparentNewType<Repr = rowan::SyntaxNode<RaTypes>>,
+    T: PartialEq<T>,
+{
+    fn eq(&self, other: &T) -> bool {
+        let t: &T = self;
+        t == other
+    }
+}
+
+impl<T> Clone for TreeArc<T>
+where
+    T: TransparentNewType<Repr = rowan::SyntaxNode<RaTypes>>,
+{
+    fn clone(&self) -> TreeArc<T> {
+        TreeArc(self.0.clone())
+    }
+}
+
+impl<T> fmt::Debug for TreeArc<T>
+where
+    T: TransparentNewType<Repr = rowan::SyntaxNode<RaTypes>>,
+    T: fmt::Debug,
+{
+    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+        fmt::Debug::fmt(&self.0, fmt)
+    }
+}
+
+#[derive(PartialEq, Eq, Hash)]
+#[repr(transparent)]
+pub struct SyntaxNode(pub(crate) rowan::SyntaxNode<RaTypes>);
+unsafe impl TransparentNewType for SyntaxNode {
+    type Repr = rowan::SyntaxNode<RaTypes>;
+}
+
+impl SyntaxNode {
+    pub(crate) fn new(green: GreenNode, errors: Vec<SyntaxError>) -> TreeArc<SyntaxNode> {
+        let ptr = TreeArc(rowan::SyntaxNode::new(green, errors));
+        TreeArc::cast(ptr)
+    }
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum Direction {
+    Next,
+    Prev,
+}
+
+impl SyntaxNode {
+    pub fn leaf_text(&self) -> Option<&SmolStr> {
+        self.0.leaf_text()
+    }
+    pub fn ancestors(&self) -> impl Iterator<Item = &SyntaxNode> {
+        crate::algo::generate(Some(self), |&node| node.parent())
+    }
+    pub fn descendants(&self) -> impl Iterator<Item = &SyntaxNode> {
+        self.preorder().filter_map(|event| match event {
+            WalkEvent::Enter(node) => Some(node),
+            WalkEvent::Leave(_) => None,
+        })
+    }
+    pub fn siblings(&self, direction: Direction) -> impl Iterator<Item = &SyntaxNode> {
+        crate::algo::generate(Some(self), move |&node| match direction {
+            Direction::Next => node.next_sibling(),
+            Direction::Prev => node.prev_sibling(),
+        })
+    }
+    pub fn preorder(&self) -> impl Iterator<Item = WalkEvent<&SyntaxNode>> {
+        self.0.preorder().map(|event| match event {
+            WalkEvent::Enter(n) => WalkEvent::Enter(SyntaxNode::from_repr(n)),
+            WalkEvent::Leave(n) => WalkEvent::Leave(SyntaxNode::from_repr(n)),
+        })
+    }
+}
+
+impl ToOwned for SyntaxNode {
+    type Owned = TreeArc<SyntaxNode>;
+    fn to_owned(&self) -> TreeArc<SyntaxNode> {
+        let ptr = TreeArc(self.0.to_owned());
+        TreeArc::cast(ptr)
+    }
+}
+
+impl SyntaxNode {
+    pub(crate) fn root_data(&self) -> &Vec<SyntaxError> {
+        self.0.root_data()
+    }
+
+    pub(crate) fn replace_with(&self, replacement: GreenNode) -> GreenNode {
+        self.0.replace_self(replacement)
+    }
+
+    pub fn kind(&self) -> SyntaxKind {
+        self.0.kind()
+    }
+
+    pub fn range(&self) -> TextRange {
+        self.0.range()
+    }
+
+    pub fn text(&self) -> SyntaxText {
+        SyntaxText::new(self)
+    }
+
+    pub fn is_leaf(&self) -> bool {
+        self.0.is_leaf()
+    }
+
+    pub fn parent(&self) -> Option<&SyntaxNode> {
+        self.0.parent().map(SyntaxNode::from_repr)
+    }
+
+    pub fn first_child(&self) -> Option<&SyntaxNode> {
+        self.0.first_child().map(SyntaxNode::from_repr)
+    }
+
+    pub fn last_child(&self) -> Option<&SyntaxNode> {
+        self.0.last_child().map(SyntaxNode::from_repr)
+    }
+
+    pub fn next_sibling(&self) -> Option<&SyntaxNode> {
+        self.0.next_sibling().map(SyntaxNode::from_repr)
+    }
+
+    pub fn prev_sibling(&self) -> Option<&SyntaxNode> {
+        self.0.prev_sibling().map(SyntaxNode::from_repr)
+    }
+
+    pub fn children(&self) -> SyntaxNodeChildren {
+        SyntaxNodeChildren(self.0.children())
+    }
+
+    pub fn memory_size_of_subtree(&self) -> usize {
+        self.0.memory_size_of_subtree()
+    }
+}
+
+impl fmt::Debug for SyntaxNode {
+    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+        write!(fmt, "{:?}@{:?}", self.kind(), self.range())?;
+        if has_short_text(self.kind()) {
+            write!(fmt, " \"{}\"", self.text())?;
+        }
+        Ok(())
+    }
+}
+
+#[derive(Debug)]
+pub struct SyntaxNodeChildren<'a>(rowan::SyntaxNodeChildren<'a, RaTypes>);
+
+impl<'a> Iterator for SyntaxNodeChildren<'a> {
+    type Item = &'a SyntaxNode;
+
+    fn next(&mut self) -> Option<&'a SyntaxNode> {
+        self.0.next().map(SyntaxNode::from_repr)
+    }
+}
+
+fn has_short_text(kind: SyntaxKind) -> bool {
+    use crate::SyntaxKind::*;
+    match kind {
+        IDENT | LIFETIME | INT_NUMBER | FLOAT_NUMBER => true,
+        _ => false,
+    }
+}