1// RUN: %check_clang_tidy %s bugprone-unintended-char-ostream-output %t
2
3namespace std {
4
5template <class _CharT, class _Traits = void> class basic_ostream {
6public:
7 basic_ostream &operator<<(int);
8 basic_ostream &operator<<(unsigned int);
9};
10
11template <class CharT, class Traits>
12basic_ostream<CharT, Traits> &operator<<(basic_ostream<CharT, Traits> &, CharT);
13template <class CharT, class Traits>
14basic_ostream<CharT, Traits> &operator<<(basic_ostream<CharT, Traits> &, char);
15template <class _Traits>
16basic_ostream<char, _Traits> &operator<<(basic_ostream<char, _Traits> &, char);
17template <class _Traits>
18basic_ostream<char, _Traits> &operator<<(basic_ostream<char, _Traits> &,
19 signed char);
20template <class _Traits>
21basic_ostream<char, _Traits> &operator<<(basic_ostream<char, _Traits> &,
22 unsigned char);
23
24using ostream = basic_ostream<char>;
25
26} // namespace std
27
28class A : public std::ostream {};
29
30using uint8_t = unsigned char;
31using int8_t = signed char;
32
33void origin_ostream(std::ostream &os) {
34 uint8_t unsigned_value = 9;
35 os << unsigned_value;
36 // CHECK-MESSAGES: [[@LINE-1]]:6: warning: 'uint8_t' (aka 'unsigned char') passed to 'operator<<' outputs as character instead of integer
37 // CHECK-FIXES: os << static_cast<unsigned int>(unsigned_value);
38
39 int8_t signed_value = 9;
40 os << signed_value;
41 // CHECK-MESSAGES: [[@LINE-1]]:6: warning: 'int8_t' (aka 'signed char') passed to 'operator<<' outputs as character instead of integer
42 // CHECK-FIXES: os << static_cast<int>(signed_value);
43
44 char char_value = 9;
45 os << char_value;
46 unsigned char unsigned_char_value = 9;
47 os << unsigned_char_value;
48 signed char signed_char_value = 9;
49 os << signed_char_value;
50}
51
52void explicit_cast_to_char_type(std::ostream &os) {
53 enum V : uint8_t {};
54 V e{};
55 os << static_cast<unsigned char>(e);
56 os << (unsigned char)(e);
57 os << (static_cast<unsigned char>(e));
58}
59
60void based_on_ostream(A &os) {
61 uint8_t unsigned_value = 9;
62 os << unsigned_value;
63 // CHECK-MESSAGES: [[@LINE-1]]:6: warning: 'uint8_t' (aka 'unsigned char') passed to 'operator<<' outputs as character instead of integer
64 // CHECK-FIXES: os << static_cast<unsigned int>(unsigned_value);
65
66 int8_t signed_value = 9;
67 os << signed_value;
68 // CHECK-MESSAGES: [[@LINE-1]]:6: warning: 'int8_t' (aka 'signed char') passed to 'operator<<' outputs as character instead of integer
69 // CHECK-FIXES: os << static_cast<int>(signed_value);
70
71 char char_value = 9;
72 os << char_value;
73}
74
75void other_ostream_template_parameters(std::basic_ostream<uint8_t> &os) {
76 uint8_t unsigned_value = 9;
77 os << unsigned_value;
78
79 int8_t signed_value = 9;
80 os << signed_value;
81
82 char char_value = 9;
83 os << char_value;
84}
85
86template <class T> class B : public std::ostream {};
87void template_based_on_ostream(B<int> &os) {
88 uint8_t unsigned_value = 9;
89 os << unsigned_value;
90 // CHECK-MESSAGES: [[@LINE-1]]:6: warning: 'uint8_t' (aka 'unsigned char') passed to 'operator<<' outputs as character instead of integer
91 // CHECK-FIXES: os << static_cast<unsigned int>(unsigned_value);
92}
93
94template<class T> void template_fn_1(T &os) {
95 uint8_t unsigned_value = 9;
96 os << unsigned_value;
97 // CHECK-MESSAGES: [[@LINE-1]]:6: warning: 'uint8_t' (aka 'unsigned char') passed to 'operator<<' outputs as character instead of integer
98 // CHECK-FIXES: os << static_cast<unsigned int>(unsigned_value);
99}
100template<class T> void template_fn_2(std::ostream &os) {
101 T unsigned_value = 9;
102 os << unsigned_value;
103 // It should be detected as well. But we cannot get the sugared type name for SubstTemplateTypeParmType.
104}
105template<class T> void template_fn_3(std::ostream &os) {
106 T unsigned_value = 9;
107 os << unsigned_value;
108}
109void call_template_fn() {
110 A a{};
111 template_fn_1(os&: a);
112 template_fn_2<uint8_t>(os&: a);
113 template_fn_3<char>(os&: a);
114}
115
116using C8 = char;
117void alias_char(std::ostream &os) {
118 C8 v = 9;
119 os << v;
120}
121
122
123#define MACRO_VARIANT_NAME a
124void macro_variant_name(std::ostream &os) {
125 uint8_t MACRO_VARIANT_NAME = 9;
126 os << MACRO_VARIANT_NAME;
127 // CHECK-MESSAGES: [[@LINE-1]]:6: warning: 'uint8_t' (aka 'unsigned char') passed to 'operator<<' outputs as character instead of integer
128 // CHECK-FIXES: os << static_cast<unsigned int>(MACRO_VARIANT_NAME);
129}
130

source code of clang-tools-extra/test/clang-tidy/checkers/bugprone/unintended-char-ostream-output.cpp