xref: /aosp_15_r20/external/llvm-libc/test/src/stdlib/AtoiTest.h (revision 71db0c75aadcf003ffe3238005f61d7618a3fead)
1 //===-- A template class for testing ato* functions -------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "src/__support/CPP/limits.h" // INT_MAX, INT_MIN, LLONG_MAX, LLONG_MIN
10 #include "src/__support/CPP/type_traits.h"
11 #include "test/UnitTest/Test.h"
12 
13 using LIBC_NAMESPACE::cpp::is_same_v;
14 
15 template <typename ReturnT>
16 struct AtoTest : public LIBC_NAMESPACE::testing::Test {
17   using FunctionT = ReturnT (*)(const char *);
18 
validNumbersAtoTest19   void validNumbers(FunctionT func) {
20     const char *zero = "0";
21     ASSERT_EQ(func(zero), static_cast<ReturnT>(0));
22 
23     const char *ten = "10";
24     ASSERT_EQ(func(ten), static_cast<ReturnT>(10));
25 
26     const char *negative_hundred = "-100";
27     ASSERT_EQ(func(negative_hundred), static_cast<ReturnT>(-100));
28 
29     const char *positive_thousand = "+1000";
30     ASSERT_EQ(func(positive_thousand), static_cast<ReturnT>(1000));
31 
32     const char *spaces_before = "     12345";
33     ASSERT_EQ(func(spaces_before), static_cast<ReturnT>(12345));
34 
35     const char *tabs_before = "\t\t\t\t67890";
36     ASSERT_EQ(func(tabs_before), static_cast<ReturnT>(67890));
37 
38     const char *letters_after = "123abc";
39     ASSERT_EQ(func(letters_after), static_cast<ReturnT>(123));
40 
41     const char *letters_between = "456def789";
42     ASSERT_EQ(func(letters_between), static_cast<ReturnT>(456));
43 
44     const char *all_together = "\t   110 times 5 = 550";
45     ASSERT_EQ(func(all_together), static_cast<ReturnT>(110));
46 
47     const char *biggest_int = "2147483647";
48     ASSERT_EQ(func(biggest_int), static_cast<ReturnT>(INT_MAX));
49 
50     const char *smallest_int = "-2147483648";
51     ASSERT_EQ(func(smallest_int), static_cast<ReturnT>(INT_MIN));
52 
53     if constexpr (sizeof(ReturnT) >= 8) {
54       const char *biggest_long_long = "9223372036854775807";
55       ASSERT_EQ(func(biggest_long_long), static_cast<ReturnT>(LLONG_MAX));
56 
57       const char *smallest_long_long = "-9223372036854775808";
58       ASSERT_EQ(func(smallest_long_long), static_cast<ReturnT>(LLONG_MIN));
59     }
60 
61     // If this is atoi and the size of int is less than the size of long, then
62     // we parse as long and cast to int to match existing behavior. This only
63     // matters for cases where the result would be outside of the int range, and
64     // those cases are undefined, so we can choose whatever output value we
65     // want. In this case we have chosen to cast since that matches existing
66     // implementations and makes differential fuzzing easier, but no user should
67     // rely on this behavior.
68     if constexpr (is_same_v<ReturnT, int> && sizeof(ReturnT) < sizeof(long)) {
69 
70       static_assert(sizeof(int) == 4);
71 
72       const char *bigger_than_biggest_int = "2147483649";
73       ASSERT_EQ(func(bigger_than_biggest_int),
74                 static_cast<ReturnT>(2147483649));
75 
76       const char *smaller_than_smallest_int = "-2147483649";
77       ASSERT_EQ(func(smaller_than_smallest_int),
78                 static_cast<ReturnT>(-2147483649));
79     }
80   }
81 
nonBaseTenWholeNumbersAtoTest82   void nonBaseTenWholeNumbers(FunctionT func) {
83     const char *hexadecimal = "0x10";
84     ASSERT_EQ(func(hexadecimal), static_cast<ReturnT>(0));
85 
86     const char *octal = "010";
87     ASSERT_EQ(func(octal), static_cast<ReturnT>(10));
88 
89     const char *decimal_point = "5.9";
90     ASSERT_EQ(func(decimal_point), static_cast<ReturnT>(5));
91   }
92 
notNumbersAtoTest93   void notNumbers(FunctionT func) {
94     const char *ten_as_word = "ten";
95     ASSERT_EQ(func(ten_as_word), static_cast<ReturnT>(0));
96 
97     const char *lots_of_letters =
98         "wtragsdhfgjykutjdyfhgnchgmjhkyurktfgjhlu;po7urtdjyfhgklyk";
99     ASSERT_EQ(func(lots_of_letters), static_cast<ReturnT>(0));
100   }
101 };
102 
103 template <typename ReturnType>
104 AtoTest(ReturnType (*)(const char *)) -> AtoTest<ReturnType>;
105 
106 #define ATOI_TEST(name, func)                                                  \
107   using LlvmLibc##name##Test = AtoTest<decltype(func(""))>;                    \
108   TEST_F(LlvmLibc##name##Test, ValidNumbers) { validNumbers(func); }           \
109   TEST_F(LlvmLibc##name##Test, NonBaseTenWholeNumbers) {                       \
110     nonBaseTenWholeNumbers(func);                                              \
111   }                                                                            \
112   TEST_F(LlvmLibc##name##Test, NotNumbers) { notNumbers(func); }
113