Add test for anonymous reexports

Author: GuillaumeGomez

src/test/rustdoc/anonymous-reexport.rs

@@ -0,0 +1,22 @@
+#![crate_name = "foo"]
+
+// This test ensures we don't display anonymous (non-inline) re-exports of public items.
+
+// @has 'foo/index.html'
+// @has - '//*[@id="main-content"]' ''
+// We check that the only "h2" present is for "Bla".
+// @count - '//*[@id="main-content"]/h2' 1
+// @has - '//*[@id="main-content"]/h2' 'Structs'
+// @count - '//*[@id="main-content"]//a[@class="struct"]' 1
+
+mod ext {
+    pub trait Foo {}
+    pub trait Bar {}
+    pub struct S;
+}
+
+pub use crate::ext::Foo as _;
+pub use crate::ext::Bar as _;
+pub use crate::ext::S as _;
+
+pub struct Bla;