analyse comments

Author: lcnr

compiler/rustc_trait_selection/src/solve/inspect/analyse.rs

@@ -54,6 +54,9 @@ impl<'a, 'tcx> InspectCandidate<'a, 'tcx> {
         self.result.map(|c| c.value.certainty)
     }
 
+    /// Visit all nested goals of this candidate without rolling
+    /// back their inference constraints. This function modifies
+    /// the state of the `infcx`.
     pub fn visit_nested_no_probe<V: ProofTreeVisitor<'tcx>>(&self, visitor: &mut V) -> V::Result {
         if self.goal.depth < visitor.config().max_depth {
             let infcx = self.goal.infcx;
@@ -129,13 +132,9 @@ impl<'a, 'tcx> InspectCandidate<'a, 'tcx> {
         V::Result::output()
     }
 
-    /// Visit the nested goals of this candidate.
-    ///
-    /// FIXME(@lcnr): we have to slightly adapt this API
-    /// to also use it to compute the most relevant goal
-    /// for fulfillment errors. Will do that once we actually
-    /// need it.
-    pub fn visit_nested<V: ProofTreeVisitor<'tcx>>(&self, visitor: &mut V) -> V::Result {
+    /// Visit all nested goals of this candidate, rolling back
+    /// all inference constraints.
+    pub fn visit_nested_in_probe<V: ProofTreeVisitor<'tcx>>(&self, visitor: &mut V) -> V::Result {
         self.goal.infcx.probe(|_| self.visit_nested_no_probe(visitor))
     }
 }