save-analysis: some refinement to the value string for variables

src/librustc_save_analysis/dump_visitor.rs

@@ -982,15 +982,23 @@ impl<'l, 'tcx: 'l, 'll, D: Dump + 'll> DumpVisitor<'l, 'tcx, 'll, D> {
  self.visit_pat(&p);
 
  for &(id, ref p, immut, _) in &collector.collected_paths {
- let mut value = if immut == ast::Mutability::Immutable {
- value.to_string()
- } else {
- "<mutable>".to_string()
+ let mut value = match immut {
+ ast::Mutability::Immutable => value.to_string(),
+ _ => String::new(),
  };
  let types = self.tcx.node_types();
- let typ = types.get(&id).map(|t| t.to_string()).unwrap_or(String::new());
- value.push_str(": ");
- value.push_str(&typ);
+ let typ = match types.get(&id) {
+ Some(typ) => {
+ let typ = typ.to_string();
+ if !value.is_empty() {
+ value.push_str(": ");
+ }
+ value.push_str(&typ);
+ typ
+ }
+ None => String::new(),
+ };
+
  // Get the span only for the name of the variable (I hope the path
  // is only ever a variable name, but who knows?).
  let sub_span = self.span.span_for_last_ident(p.span);