Add a test for #2256

tests/source/issue-2256.rs

@@ -0,0 +1,12 @@
+// こんにちは
+use std::{};
+use std::borrow::Cow;
+
+/* comment */ use std::{};
+/* comment */ use std::{};
+
+
+
+
+
+/* comment */ use std::{};

tests/target/issue-2256.rs

@@ -0,0 +1,7 @@
+// こんにちは
+use std::borrow::Cow;
+
+/* comment */
+/* comment */
+
+/* comment */