Hide trait impl with private trait type parameter

Trait's implementations with private type parameters were displayed in
the implementing struct's documentation until now.

With this change any trait implementation that uses a private type
parameter is now hidden in the docs.

1 files changed, 9 insertions, 0 deletions

diff --git a/src/librustdoc/passes/mod.rs b/src/librustdoc/passes/mod.rs
index 77d97c84c99..3e15d3d3007 100644
--- a/src/librustdoc/passes/mod.rs
+++ b/src/librustdoc/passes/mod.rs
@@ -184,6 +184,15 @@ impl<'a> fold::DocFolder for ImplStripper<'a> {
                     return None;
                 }
             }
+            if let Some(generics) = imp.trait_.as_ref().and_then(|t| t.generics()) {
+                for typaram in generics {
+                    if let Some(did) = typaram.def_id() {
+                        if did.is_local() && !self.retained.contains(&did) {
+                            return None;
+                        }
+                    }
+                }
+            }
         }
         self.fold_item_recur(i)
     }