Add and update test for #3515

Author: topecongiro

tests/source/issue-3515.rs

@@ -0,0 +1,6 @@
+// rustfmt-reorder_imports: false
+
+use std :: fmt :: { self , Display } ;
+use std :: collections :: HashMap ;
+
+fn main() {}

tests/target/issue-3515.rs

@@ -0,0 +1,6 @@
+// rustfmt-reorder_imports: false
+
+use std::fmt::{self, Display};
+use std::collections::HashMap;
+
+fn main() {}

tests/target/long-use-statement-issue-3154.rs

@@ -1,3 +1,3 @@
 // rustfmt-reorder_imports: false
 
-pub use self :: super :: super :: super :: root::mozilla::detail::StringClassFlags as nsTStringRepr_ClassFlags ;
+pub use self::super::super::super::root::mozilla::detail::StringClassFlags as nsTStringRepr_ClassFlags;