3 files changed, 33 insertions, 10 deletions

diff --git a/crates/ra_ide_api/src/goto_definition.rs b/crates/ra_ide_api/src/goto_definition.rs
index 40a2bd148..163781f88 100644
--- a/crates/ra_ide_api/src/goto_definition.rs
+++ b/crates/ra_ide_api/src/goto_definition.rs
@@ -25,6 +25,7 @@ pub(crate) fn goto_definition(
     None
 }
 
+#[derive(Debug)]
 pub(crate) enum ReferenceResult {
     Exact(NavigationTarget),
     Approximate(Vec<NavigationTarget>),
diff --git a/crates/ra_ide_api/src/hover.rs b/crates/ra_ide_api/src/hover.rs
index 397b56786..6545a2581 100644
--- a/crates/ra_ide_api/src/hover.rs
+++ b/crates/ra_ide_api/src/hover.rs
@@ -1,7 +1,7 @@
 use ra_db::SourceDatabase;
 use ra_syntax::{
     AstNode, ast,
-    algo::{find_covering_element, find_node_at_offset, find_token_at_offset},
+    algo::{find_covering_element, find_node_at_offset, ancestors_at_offset},
 };
 use hir::HirDisplay;
 
@@ -104,12 +104,8 @@ pub(crate) fn hover(db: &RootDatabase, position: FilePosition) -> Option<RangeIn
     }
 
     if range.is_none() {
-        let node = find_token_at_offset(file.syntax(), position.offset).find_map(|token| {
-            token
-                .parent()
-                .ancestors()
-                .find(|n| ast::Expr::cast(*n).is_some() || ast::Pat::cast(*n).is_some())
-        })?;
+        let node = ancestors_at_offset(file.syntax(), position.offset)
+            .find(|n| ast::Expr::cast(*n).is_some() || ast::Pat::cast(*n).is_some())?;
         let frange = FileRange { file_id: position.file_id, range: node.range() };
         res.extend(type_of(db, frange).map(rust_code_markup));
         range = Some(node.range());
@@ -398,6 +394,17 @@ The Some variant
     }
 
     #[test]
+    fn hover_local_var_edge() {
+        let (analysis, position) = single_file_with_position(
+            "
+fn func(foo: i32) { if true { <|>foo; }; }
+",
+        );
+        let hover = analysis.hover(position).unwrap().unwrap();
+        assert_eq!(trim_markup_opt(hover.info.first()), Some("i32"));
+    }
+
+    #[test]
     fn test_type_of_for_function() {
         let (analysis, range) = single_file_with_range(
             "
diff --git a/crates/ra_syntax/src/algo.rs b/crates/ra_syntax/src/algo.rs
index 1f68fe467..d31d00343 100644
--- a/crates/ra_syntax/src/algo.rs
+++ b/crates/ra_syntax/src/algo.rs
@@ -1,5 +1,7 @@
 pub mod visit;
 
+use itertools::Itertools;
+
 use crate::{SyntaxNode, TextRange, TextUnit, AstNode, Direction, SyntaxToken, SyntaxElement};
 
 pub use rowan::TokenAtOffset;
@@ -12,6 +14,20 @@ pub fn find_token_at_offset(node: &SyntaxNode, offset: TextUnit) -> TokenAtOffse
     }
 }
 
+/// Returns ancestors of the node at the offset, sorted by length. This should
+/// do the right thing at an edge, e.g. when searching for expressions at `{
+/// <|>foo }` we will get the name reference instead of the whole block, which
+/// we would get if we just did `find_token_at_offset(...).flat_map(|t|
+/// t.parent().ancestors())`.
+pub fn ancestors_at_offset(
+    node: &SyntaxNode,
+    offset: TextUnit,
+) -> impl Iterator<Item = &SyntaxNode> {
+    find_token_at_offset(node, offset)
+        .map(|token| token.parent().ancestors())
+        .kmerge_by(|node1, node2| node1.range().len() < node2.range().len())
+}
+
 /// Finds a node of specific Ast type at offset. Note that this is slightly
 /// imprecise: if the cursor is strictly between two nodes of the desired type,
 /// as in
@@ -20,10 +36,9 @@ pub fn find_token_at_offset(node: &SyntaxNode, offset: TextUnit) -> TokenAtOffse
 /// struct Foo {}|struct Bar;
 /// ```
 ///
-/// then the left node will be silently preferred.
+/// then the shorter node will be silently preferred.
 pub fn find_node_at_offset<N: AstNode>(syntax: &SyntaxNode, offset: TextUnit) -> Option<&N> {
-    find_token_at_offset(syntax, offset)
-        .find_map(|leaf| leaf.parent().ancestors().find_map(N::cast))
+    ancestors_at_offset(syntax, offset).find_map(N::cast)
 }
 
 /// Finds the first sibling in the given direction which is not `trivia`