Warn unused trait imports

src/test/compile-fail/dep-graph-trait-impl-two-traits-same-method.rs

@@ -15,6 +15,7 @@
 
 #![feature(rustc_attrs)]
 #![allow(dead_code)]
+#![allow(unused_imports)]
 
 fn main() { }
 

src/test/compile-fail/lint-unused-imports.rs

@@ -24,6 +24,8 @@ use test::A;       //~ ERROR unused import
 // Be sure that if we just bring some methods into scope that they're also
 // counted as being used.
 use test::B;
+// But only when actually used: do not get confused by the method with the same name.
+use test::B2; //~ ERROR unused import
 
 // Make sure this import is warned about when at least one of its imported names
 // is unused
@@ -37,6 +39,7 @@ mod test2 {
 mod test {
     pub trait A { fn a(&self) {} }
     pub trait B { fn b(&self) {} }
+    pub trait B2 { fn b(&self) {} }
     pub struct C;
     impl A for C {}
     impl B for C {}