[clang-tidy] Add clang-tidy check for unique_ptr's reset+release -> move

Replace x.reset(y.release()); with x = std::move(y);
If y is rvalue, replace with x = y; instead.

http://reviews.llvm.org/D6485

Patch by Alexey Sokolov!

llvm-svn: 223460

1 files changed, 48 insertions, 0 deletions

diff --git a/clang-tools-extra/test/clang-tidy/misc-uniqueptr-reset-release.cpp b/clang-tools-extra/test/clang-tidy/misc-uniqueptr-reset-release.cpp
new file mode 100644
index 00000000000..763a428ecd9
--- /dev/null
+++ b/clang-tools-extra/test/clang-tidy/misc-uniqueptr-reset-release.cpp
@@ -0,0 +1,48 @@
+// RUN: $(dirname %s)/check_clang_tidy.sh %s misc-uniqueptr-reset-release %t
+// REQUIRES: shell
+
+namespace std {
+template <typename T>
+struct unique_ptr {
+  unique_ptr<T>();
+  explicit unique_ptr<T>(T *);
+  template <typename U>
+  unique_ptr<T>(unique_ptr<U> &&);
+  void reset(T *);
+  T *release();
+};
+} // namespace std
+
+struct Foo {};
+struct Bar : Foo {};
+
+std::unique_ptr<Foo> Create();
+std::unique_ptr<Foo> &Look();
+std::unique_ptr<Foo> *Get();
+
+void f() {
+  std::unique_ptr<Foo> a, b;
+  std::unique_ptr<Bar> c;
+  std::unique_ptr<Foo> *x = &a;
+  std::unique_ptr<Foo> *y = &b;
+
+  a.reset(b.release());
+  // CHECK-MESSAGES: :[[@LINE-1]]:5: warning: prefer ptr1 = std::move(ptr2) over ptr1.reset(ptr2.release()) [misc-uniqueptr-reset-release]
+  // CHECK-FIXES: a = std::move(b);
+  a.reset(c.release());
+  // CHECK-MESSAGES: :[[@LINE-1]]:5: warning: prefer ptr1 = std::move(ptr2)
+  // CHECK-FIXES: a = std::move(c);
+  a.reset(Create().release());
+  // CHECK-MESSAGES: :[[@LINE-1]]:5: warning: prefer ptr1 = std::move(ptr2)
+  // CHECK-FIXES: a = Create();
+  x->reset(y->release());
+  // CHECK-MESSAGES: :[[@LINE-1]]:6: warning: prefer ptr1 = std::move(ptr2)
+  // CHECK-FIXES: *x = std::move(*y);
+  Look().reset(Look().release());
+  // CHECK-MESSAGES: :[[@LINE-1]]:10: warning: prefer ptr1 = std::move(ptr2)
+  // CHECK-FIXES: Look() = std::move(Look());
+  Get()->reset(Get()->release());
+  // CHECK-MESSAGES: :[[@LINE-1]]:10: warning: prefer ptr1 = std::move(ptr2)
+  // CHECK-FIXES: *Get() = std::move(*Get());
+}
+