Do not trigger trailing_empty_array in tests

Author: alex-semenyuk

clippy_lints/src/trailing_empty_array.rs

@@ -1,5 +1,5 @@
 use clippy_utils::diagnostics::span_lint_and_help;
-use clippy_utils::has_repr_attr;
+use clippy_utils::{has_repr_attr, is_in_test};
 use rustc_hir::{Item,ItemKind};
 use rustc_lint::{LateContext,LateLintPass};
 use rustc_middle::ty;
@@ -37,7 +37,10 @@ declare_lint_pass!(TrailingEmptyArray => [TRAILING_EMPTY_ARRAY]);
 
 impl<'tcx>LateLintPass<'tcx>forTrailingEmptyArray{
 fncheck_item(&mutself,cx:&LateContext<'tcx>,item:&'tcxItem<'tcx>){
-ifis_struct_with_trailing_zero_sized_array(cx, item) && !has_repr_attr(cx, item.hir_id()){
+ifis_struct_with_trailing_zero_sized_array(cx, item)
+ && !has_repr_attr(cx, item.hir_id())
+ && !is_in_test(cx.tcx, item.hir_id())
+{
 span_lint_and_help(
  cx,
 TRAILING_EMPTY_ARRAY,

tests/ui/trailing_empty_array.rs

@@ -192,3 +192,17 @@ type C = ConstParamNoDefault<0>;
 typeD = ConstParamNonZeroDefault<0>;
 
 fnmain(){}
+
+#[cfg(test)]
+mod tests {
+pubstructFriend{
+age:u8,
+}
+
+#[test]
+fnoldest_empty_is_none(){
+structMichael{
+friends:[Friend;0],
+}
+}
+}