visitor

1 files changed, 67 insertions, 0 deletions

diff --git a/crates/libeditor/src/symbols.rs b/crates/libeditor/src/symbols.rs
new file mode 100644
index 000000000..3faf96868
--- /dev/null
+++ b/crates/libeditor/src/symbols.rs
@@ -0,0 +1,67 @@
+use libsyntax2::{
+    SyntaxKind, SyntaxNodeRef, SyntaxRoot, AstNode,
+    ast::{self, NameOwner},
+    algo::{
+        visit::{visitor, Visitor},
+        walk::{walk, WalkEvent},
+    },
+};
+use TextRange;
+
+#[derive(Debug)]
+pub struct FileSymbol {
+    pub parent: Option<usize>,
+    pub name: String,
+    pub name_range: TextRange,
+    pub node_range: TextRange,
+    pub kind: SyntaxKind,
+}
+
+
+pub fn file_symbols(file: &ast::File) -> Vec<FileSymbol> {
+    let mut res = Vec::new();
+    let mut stack = Vec::new();
+    let syntax = file.syntax();
+
+    for event in walk(syntax.as_ref()) {
+        match event {
+            WalkEvent::Enter(node) => {
+                match to_symbol(node) {
+                    Some(mut symbol) => {
+                        symbol.parent = stack.last().map(|&n| n);
+                        stack.push(res.len());
+                        res.push(symbol);
+                    }
+                    None => (),
+                }
+            }
+            WalkEvent::Exit(node) => {
+                if to_symbol(node).is_some() {
+                    stack.pop().unwrap();
+                }
+            }
+        }
+    }
+    res
+}
+
+fn to_symbol(node: SyntaxNodeRef) -> Option<FileSymbol> {
+    fn decl<'a, N: NameOwner<&'a SyntaxRoot>>(node: N) -> Option<FileSymbol> {
+        let name = node.name()?;
+        Some(FileSymbol {
+            parent: None,
+            name: name.text(),
+            name_range: name.syntax().range(),
+            node_range: node.syntax().range(),
+            kind: node.syntax().kind(),
+        })
+    }
+
+    visitor()
+        .visit(decl::<ast::Function<_>>)
+        .visit(decl::<ast::Struct<_>>)
+        .visit(decl::<ast::Enum<_>>)
+        .visit(decl::<ast::Trait<_>>)
+        .visit(decl::<ast::Module<_>>)
+        .accept(node)?
+}