Verify assign operator signatures.

Summary: Warn when the return type of assign operators is not Class&.

Reviewers: alexfh

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D6667

llvm-svn: 228583

1 files changed, 52 insertions, 0 deletions

diff --git a/clang-tools-extra/test/clang-tidy/misc-assign-operator-signature.cpp b/clang-tools-extra/test/clang-tidy/misc-assign-operator-signature.cpp
new file mode 100644
index 00000000000..bdeca538954
--- /dev/null
+++ b/clang-tools-extra/test/clang-tidy/misc-assign-operator-signature.cpp
@@ -0,0 +1,52 @@
+// RUN: $(dirname %s)/check_clang_tidy.sh %s misc-assign-operator-signature %t
+// REQUIRES: shell
+
+struct Good {
+  Good& operator=(const Good&);
+  Good& operator=(Good&&);
+
+  // Assign from other types is fine too.
+  Good& operator=(int);
+};
+
+struct AlsoGood {
+  // By value is also fine.
+  AlsoGood& operator=(AlsoGood);
+};
+
+struct BadReturn {
+  void operator=(const BadReturn&);
+  // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: operator=() should return 'BadReturn&' [misc-assign-operator-signature]
+  const BadReturn& operator=(BadReturn&&);
+  // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: operator=() should return 'Bad
+};
+struct BadReturn2 {
+  BadReturn2&& operator=(const BadReturn2&);
+  // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: operator=() should return 'Bad
+  int operator=(BadReturn2&&);
+  // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: operator=() should return 'Bad
+};
+
+struct BadArgument {
+  BadArgument& operator=(BadArgument&);
+  // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: operator=() should take 'BadArgument const&', 'BadArgument&&' or 'BadArgument'
+  BadArgument& operator=(const BadArgument&&);
+  // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: operator=() should take 'BadAr
+};
+
+struct BadModifier {
+  BadModifier& operator=(const BadModifier&) const;
+  // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: operator=() should not be marked 'const'
+};
+
+struct Deleted {
+  // We don't check the return value of deleted operators.
+  void operator=(const Deleted&) = delete;
+  void operator=(Deleted&&) = delete;
+};
+
+class Private {
+  // We don't check the return value of private operators.
+  // Pre-C++11 way of disabling assignment.
+  void operator=(const Private &);
+};