rustdoc: Strip impls of stripped private types

In strip-private, also strip impls of traits for private types. This
fixes the search index so searching for "drop", "eq", etc doesn't throw
an exception.

1 files changed, 10 insertions, 2 deletions

diff --git a/src/librustdoc/passes.rs b/src/librustdoc/passes.rs
index 30643737078..fce4cab52c9 100644
--- a/src/librustdoc/passes.rs
+++ b/src/librustdoc/passes.rs
@@ -110,8 +110,16 @@ impl<'a> fold::DocFolder for Stripper<'a> {
             // handled below
             clean::ModuleItem(..) => {}
 
-            // impls/tymethods have no control over privacy
-            clean::ImplItem(..) | clean::TyMethodItem(..) => {}
+            // trait impls for private items should be stripped
+            clean::ImplItem(clean::Impl{ for_: clean::ResolvedPath{ id: ref for_id, .. }, .. }) => {
+                if !self.exported_items.contains(for_id) {
+                    return None;
+                }
+            }
+            clean::ImplItem(..) => {}
+
+            // tymethods have no control over privacy
+            clean::TyMethodItem(..) => {}
         }
 
         let fastreturn = match i.inner {