xref: /llvm-project/clang-tools-extra/test/clang-tidy/checkers/fuchsia/trailing-return.cpp (revision 89a1d03e2b379e325daa5249411e414bbd995b5e)
1 // RUN: %check_clang_tidy -std=c++17-or-later %s fuchsia-trailing-return %t
2 
add_one(const int arg)3 int add_one(const int arg) { return arg; }
4 
get_add_one()5 auto get_add_one() -> int (*)(const int) {
6   // CHECK-MESSAGES: [[@LINE-1]]:1: warning: a trailing return type is disallowed for this function declaration
7   // CHECK-NEXT: auto get_add_one() -> int (*)(const int) {
8   return add_one;
9 }
10 
__anon217685100102(double x, double y) 11 auto lambda = [](double x, double y) {return x + y;};
12 
__anon217685100202(double x, double y) 13 auto lambda2 = [](double x, double y) -> double {return x + y;};
14 
main()15 int main() {
16   get_add_one()(5);
17   return 0;
18 }
19 
20 template <typename T1, typename T2>
fn(const T1 & lhs,const T2 & rhs)21 auto fn(const T1 &lhs, const T2 &rhs) -> decltype(lhs + rhs) {
22   return lhs + rhs;
23 }
24 
25 // Now check that implicit and explicit C++17 deduction guides don't trigger this warning (PR#47614).
26 
27 template <typename T>
28 struct ImplicitDeductionGuides {
29   ImplicitDeductionGuides(const T &);
30 };
31 
32 template <typename A, typename B>
33 struct pair {
34   A first;
35   B second;
36 };
37 
38 template <typename T>
39 struct UserDefinedDeductionGuides {
40   UserDefinedDeductionGuides(T);
41   template <typename T1, typename T2>
42   UserDefinedDeductionGuides(T1, T2);
43 };
44 
45 template <typename T1, typename T2>
46 UserDefinedDeductionGuides(T1, T2) -> UserDefinedDeductionGuides<pair<T1, T2>>;
47 
foo()48 void foo() {
49   ImplicitDeductionGuides X(42);
50   UserDefinedDeductionGuides s(1, "abc");
51 }
52