xref: /aosp_15_r20/external/fmtlib/test/scan-test.cc (revision 5c90c05cd622c0a81b57953a4d343e0e489f2e08)
1 // Formatting library for C++ - scanning API test
2 //
3 // Copyright (c) 2019 - present, Victor Zverovich
4 // All rights reserved.
5 //
6 // For the license information refer to format.h.
7 
8 #include "scan.h"
9 
10 #include <time.h>
11 
12 #include <climits>
13 #include <thread>
14 
15 #include "fmt/os.h"
16 #include "gmock/gmock.h"
17 #include "gtest-extra.h"
18 
TEST(scan_test,read_text)19 TEST(scan_test, read_text) {
20   fmt::string_view s = "foo";
21   auto end = fmt::scan_to(s, "foo");
22   EXPECT_EQ(end, s.end());
23   EXPECT_THROW_MSG(fmt::scan<int>("fob", "foo"), fmt::format_error,
24                    "invalid input");
25 }
26 
TEST(scan_test,read_int)27 TEST(scan_test, read_int) {
28   EXPECT_EQ(fmt::scan<int>("42", "{}")->value(), 42);
29   EXPECT_EQ(fmt::scan<int>("-42", "{}")->value(), -42);
30   EXPECT_EQ(fmt::scan<int>("42", "{:}")->value(), 42);
31   EXPECT_THROW_MSG(fmt::scan<int>(std::to_string(INT_MAX + 1u), "{}"),
32                    fmt::format_error, "number is too big");
33 }
34 
TEST(scan_test,read_long_long)35 TEST(scan_test, read_long_long) {
36   EXPECT_EQ(fmt::scan<long long>("42", "{}")->value(), 42);
37   EXPECT_EQ(fmt::scan<long long>("-42", "{}")->value(), -42);
38 }
39 
TEST(scan_test,read_uint)40 TEST(scan_test, read_uint) {
41   EXPECT_EQ(fmt::scan<unsigned>("42", "{}")->value(), 42);
42   EXPECT_THROW_MSG(fmt::scan<unsigned>("-42", "{}"), fmt::format_error,
43                    "invalid input");
44 }
45 
TEST(scan_test,read_ulong_long)46 TEST(scan_test, read_ulong_long) {
47   EXPECT_EQ(fmt::scan<unsigned long long>("42", "{}")->value(), 42);
48   EXPECT_THROW_MSG(fmt::scan<unsigned long long>("-42", "{}")->value(),
49                    fmt::format_error, "invalid input");
50 }
51 
TEST(scan_test,read_hex)52 TEST(scan_test, read_hex) {
53   EXPECT_EQ(fmt::scan<unsigned>("2a", "{:x}")->value(), 42);
54   auto num_digits = std::numeric_limits<unsigned>::digits / 4;
55   EXPECT_THROW_MSG(
56       fmt::scan<unsigned>(fmt::format("1{:0{}}", 0, num_digits), "{:x}")
57           ->value(),
58       fmt::format_error, "number is too big");
59 }
60 
TEST(scan_test,read_string)61 TEST(scan_test, read_string) {
62   EXPECT_EQ(fmt::scan<std::string>("foo", "{}")->value(), "foo");
63 }
64 
TEST(scan_test,read_string_view)65 TEST(scan_test, read_string_view) {
66   EXPECT_EQ(fmt::scan<fmt::string_view>("foo", "{}")->value(), "foo");
67 }
68 
TEST(scan_test,separator)69 TEST(scan_test, separator) {
70   int n1 = 0, n2 = 0;
71   fmt::scan_to("10 20", "{} {}", n1, n2);
72   EXPECT_EQ(n1, 10);
73   EXPECT_EQ(n2, 20);
74 }
75 
76 struct num {
77   int value;
78 };
79 
80 namespace fmt {
81 template <> struct scanner<num> {
82   bool hex = false;
83 
parsefmt::scanner84   auto parse(scan_parse_context& ctx) -> scan_parse_context::iterator {
85     auto it = ctx.begin(), end = ctx.end();
86     if (it != end && *it == 'x') {
87       hex = true;
88       ++it;
89     }
90     if (it != end && *it != '}') report_error("invalid format");
91     return it;
92   }
93 
94   template <class ScanContext>
scanfmt::scanner95   auto scan(num& n, ScanContext& ctx) const -> typename ScanContext::iterator {
96     return hex ? scan_to(ctx, "{:x}", n.value) : scan_to(ctx, "{}", n.value);
97   }
98 };
99 }  // namespace fmt
100 
TEST(scan_test,read_custom)101 TEST(scan_test, read_custom) {
102   EXPECT_EQ(fmt::scan<num>("42", "{}")->value().value, 42);
103   EXPECT_EQ(fmt::scan<num>("2a", "{:x}")->value().value, 42);
104 }
105 
TEST(scan_test,invalid_format)106 TEST(scan_test, invalid_format) {
107   EXPECT_THROW_MSG(fmt::scan_to("", "{}"), fmt::format_error,
108                    "argument index out of range");
109   EXPECT_THROW_MSG(fmt::scan_to("", "{"), fmt::format_error,
110                    "invalid format string");
111 }
112 
113 namespace std {
114 using fmt::scan;
115 using fmt::scan_error;
116 }  // namespace std
117 
TEST(scan_test,example)118 TEST(scan_test, example) {
119   // Example from https://wg21.link/p1729r3.
120   if (auto result = std::scan<std::string, int>("answer = 42", "{} = {}")) {
121     auto range = result->range();
122     EXPECT_EQ(range.begin(), range.end());
123     EXPECT_EQ(result->begin(), result->end());
124 #ifdef __cpp_structured_bindings
125     const auto& [key, value] = result->values();
126     EXPECT_EQ(key, "answer");
127     EXPECT_EQ(value, 42);
128 #endif
129   } else {
130     std::scan_error error = result.error();
131     (void)error;
132     FAIL();
133   }
134 }
135 
TEST(scan_test,end_of_input)136 TEST(scan_test, end_of_input) { fmt::scan<int>("", "{}"); }
137 
138 #if FMT_USE_FCNTL
TEST(scan_test,file)139 TEST(scan_test, file) {
140   auto pipe = fmt::pipe();
141 
142   fmt::string_view input = "10 20";
143   pipe.write_end.write(input.data(), input.size());
144   pipe.write_end.close();
145 
146   int n1 = 0, n2 = 0;
147   fmt::buffered_file f = pipe.read_end.fdopen("r");
148   fmt::scan_to(f.get(), "{} {}", n1, n2);
149   EXPECT_EQ(n1, 10);
150   EXPECT_EQ(n2, 20);
151 }
152 
TEST(scan_test,lock)153 TEST(scan_test, lock) {
154   auto pipe = fmt::pipe();
155 
156   std::thread producer([&]() {
157     fmt::string_view input = "42 ";
158     for (int i = 0; i < 1000; ++i)
159       pipe.write_end.write(input.data(), input.size());
160     pipe.write_end.close();
161   });
162 
163   std::atomic<int> count(0);
164   fmt::buffered_file f = pipe.read_end.fdopen("r");
165   auto fun = [&]() {
166     int value = 0;
167     while (fmt::scan_to(f.get(), "{}", value)) {
168       if (value != 42) {
169         pipe.read_end.close();
170         EXPECT_EQ(value, 42);
171         break;
172       }
173       ++count;
174     }
175   };
176   std::thread consumer1(fun);
177   std::thread consumer2(fun);
178 
179   producer.join();
180   consumer1.join();
181   consumer2.join();
182   EXPECT_EQ(count, 1000);
183 }
184 #endif  // FMT_USE_FCNTL
185