2 files changed, 9 insertions, 8 deletions

diff --git a/crates/ra_syntax/src/ptr.rs b/crates/ra_syntax/src/ptr.rs
index b0816b135..cee9503ca 100644
--- a/crates/ra_syntax/src/ptr.rs
+++ b/crates/ra_syntax/src/ptr.rs
@@ -3,7 +3,7 @@ use std::{
     iter::successors,
 };
 use crate::{
-    AstNode, SourceFile, SyntaxKind, SyntaxNode, TextRange,
+    AstNode, SyntaxKind, SyntaxNode, TextRange,
 };
 
 /// A pointer to a syntax node inside a file. It can be used to remember a
@@ -19,8 +19,9 @@ impl SyntaxNodePtr {
         SyntaxNodePtr { range: node.range(), kind: node.kind() }
     }
 
-    pub fn to_node(self, source_file: &SourceFile) -> &SyntaxNode {
-        successors(Some(source_file.syntax()), |&node| {
+    pub fn to_node(self, root: &SyntaxNode) -> &SyntaxNode {
+        assert!(root.parent().is_none());
+        successors(Some(root), |&node| {
             node.children().find(|it| self.range.is_subrange(&it.range()))
         })
         .find(|it| it.range() == self.range && it.kind() == self.kind)
@@ -55,8 +56,8 @@ impl<N: AstNode> AstPtr<N> {
         AstPtr { raw: SyntaxNodePtr::new(node.syntax()), _ty: PhantomData }
     }
 
-    pub fn to_node(self, source_file: &SourceFile) -> &N {
-        let syntax_node = self.raw.to_node(source_file);
+    pub fn to_node(self, root: &SyntaxNode) -> &N {
+        let syntax_node = self.raw.to_node(root);
         N::cast(syntax_node).unwrap()
     }
 
@@ -73,11 +74,11 @@ impl<N: AstNode> From<AstPtr<N>> for SyntaxNodePtr {
 
 #[test]
 fn test_local_syntax_ptr() {
-    use crate::{ast, AstNode};
+    use crate::{ast, AstNode, SourceFile};
 
     let file = SourceFile::parse("struct Foo { f: u32, }");
     let field = file.syntax().descendants().find_map(ast::NamedFieldDef::cast).unwrap();
     let ptr = SyntaxNodePtr::new(field.syntax());
-    let field_syntax = ptr.to_node(&file);
+    let field_syntax = ptr.to_node(file.syntax());
     assert_eq!(field.syntax(), &*field_syntax);
 }
diff --git a/crates/ra_syntax/src/syntax_node.rs b/crates/ra_syntax/src/syntax_node.rs
index 92c15234e..80054f529 100644
--- a/crates/ra_syntax/src/syntax_node.rs
+++ b/crates/ra_syntax/src/syntax_node.rs
@@ -392,7 +392,7 @@ impl SyntaxNode {
         // `range` private afterwards
         let mut ptr = SyntaxNodePtr::new(self);
         ptr.range = TextRange::offset_len(ptr.range().start(), len);
-        return ptr.to_node(&file).to_owned();
+        return ptr.to_node(file.syntax()).to_owned();
     }
 
     fn position_of_child(&self, child: SyntaxElement) -> usize {