Merge #316

316: Fix handling of nested self in paths r=matklad a=DJMcNab

See https://github.com/rust-analyzer/rust-analyzer/issues/231#issuecomment-442449505.

Co-authored-by: DJMcNab <36049421+djmcnab@users.noreply.github.com>

crates/ra_syntax/src/ast.rs

@@ -284,7 +284,7 @@ impl<'a> IfExpr<'a> {
     }
 }
 
-#[derive(Debug, Clone, Copy)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum PathSegmentKind<'a> {
     Name(NameRef<'a>),
     SelfKw,