1 files changed, 43 insertions, 0 deletions
diff --git a/tools/clang-tidy/test/performance-implicit-conversion-in-loop.cpp b/tools/clang-tidy/test/performance-implicit-conversion-in-loop.cpp
new file mode 100644
index 0000000000..75ed510f3f
--- /dev/null
+++ b/tools/clang-tidy/test/performance-implicit-conversion-in-loop.cpp
@@ -0,0 +1,43 @@
+// Iterator returning by value.
+template <typename T>
+struct Iterator {
+  void operator++();
+  T operator*();
+  bool operator!=(const Iterator& other);
+};
+
+// The template argument is an iterator type, and a view is an object you can
+// run a for loop on.
+template <typename T>
+struct View {
+  T begin();
+  T end();
+};
+
+// With this class, the implicit conversion is a call to the (implicit)
+// constructor of the class.
+template <typename T>
+class ImplicitWrapper {
+ public:
+  // Implicit!
+  ImplicitWrapper(const T& t);
+};
+
+template <typename T>
+class OperatorWrapper {
+ public:
+  OperatorWrapper() = delete;
+};
+
+struct SimpleClass {
+  int foo;
+  operator OperatorWrapper<SimpleClass>();
+};
+
+typedef View<Iterator<SimpleClass>> SimpleView;
+
+void ImplicitSimpleClassIterator() {
+  for (const ImplicitWrapper<SimpleClass>& foo : SimpleView()) {}
+  for (const ImplicitWrapper<SimpleClass> foo : SimpleView()) {}
+  for (ImplicitWrapper<SimpleClass> foo : SimpleView()) {}
+}