// Copyright 2017 The Abseil Authors. // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // https://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. // See the License for the specific language governing permissions and // limitations under the License. // Unit tests for all str_cat.h functions #include "absl/strings/str_cat.h" #include #include #include #include "gtest/gtest.h" #include "absl/strings/str_format.h" #include "absl/strings/substitute.h" #ifdef __ANDROID__ // Android assert messages only go to system log, so death tests cannot inspect // the message for matching. #define ABSL_EXPECT_DEBUG_DEATH(statement, regex) \ EXPECT_DEBUG_DEATH(statement, ".*") #else #define ABSL_EXPECT_DEBUG_DEATH(statement, regex) \ EXPECT_DEBUG_DEATH(statement, regex) #endif namespace { // Test absl::StrCat of ints and longs of various sizes and signdedness. TEST(StrCat, Ints) { const short s = -1; // NOLINT(runtime/int) const uint16_t us = 2; const int i = -3; const unsigned int ui = 4; const long l = -5; // NOLINT(runtime/int) const unsigned long ul = 6; // NOLINT(runtime/int) const long long ll = -7; // NOLINT(runtime/int) const unsigned long long ull = 8; // NOLINT(runtime/int) const ptrdiff_t ptrdiff = -9; const size_t size = 10; const intptr_t intptr = -12; const uintptr_t uintptr = 13; std::string answer; answer = absl::StrCat(s, us); EXPECT_EQ(answer, "-12"); answer = absl::StrCat(i, ui); EXPECT_EQ(answer, "-34"); answer = absl::StrCat(l, ul); EXPECT_EQ(answer, "-56"); answer = absl::StrCat(ll, ull); EXPECT_EQ(answer, "-78"); answer = absl::StrCat(ptrdiff, size); EXPECT_EQ(answer, "-910"); answer = absl::StrCat(ptrdiff, intptr); EXPECT_EQ(answer, "-9-12"); answer = absl::StrCat(uintptr, 0); EXPECT_EQ(answer, "130"); } TEST(StrCat, Enums) { enum SmallNumbers { One = 1, Ten = 10 } e = Ten; EXPECT_EQ("10", absl::StrCat(e)); EXPECT_EQ("-5", absl::StrCat(SmallNumbers(-5))); enum class Option { Boxers = 1, Briefs = -1 }; EXPECT_EQ("-1", absl::StrCat(Option::Briefs)); enum class Airplane : uint64_t { Airbus = 1, Boeing = 1000, Canary = 10000000000 // too big for "int" }; EXPECT_EQ("10000000000", absl::StrCat(Airplane::Canary)); enum class TwoGig : int32_t { TwoToTheZero = 1, TwoToTheSixteenth = 1 << 16, TwoToTheThirtyFirst = INT32_MIN }; EXPECT_EQ("65536", absl::StrCat(TwoGig::TwoToTheSixteenth)); EXPECT_EQ("-2147483648", absl::StrCat(TwoGig::TwoToTheThirtyFirst)); EXPECT_EQ("-1", absl::StrCat(static_cast(-1))); enum class FourGig : uint32_t { TwoToTheZero = 1, TwoToTheSixteenth = 1 << 16, TwoToTheThirtyFirst = 1U << 31 // too big for "int" }; EXPECT_EQ("65536", absl::StrCat(FourGig::TwoToTheSixteenth)); EXPECT_EQ("2147483648", absl::StrCat(FourGig::TwoToTheThirtyFirst)); EXPECT_EQ("4294967295", absl::StrCat(static_cast(-1))); EXPECT_EQ("10000000000", absl::StrCat(Airplane::Canary)); } TEST(StrCat, Basics) { std::string result; std::string strs[] = {"Hello", "Cruel", "World"}; std::string stdstrs[] = { "std::Hello", "std::Cruel", "std::World" }; absl::string_view pieces[] = {"Hello", "Cruel", "World"}; const char* c_strs[] = { "Hello", "Cruel", "World" }; int32_t i32s[] = {'H', 'C', 'W'}; uint64_t ui64s[] = {12345678910LL, 10987654321LL}; EXPECT_EQ(absl::StrCat(), ""); result = absl::StrCat(false, true, 2, 3); EXPECT_EQ(result, "0123"); result = absl::StrCat(-1); EXPECT_EQ(result, "-1"); result = absl::StrCat(absl::SixDigits(0.5)); EXPECT_EQ(result, "0.5"); result = absl::StrCat(strs[1], pieces[2]); EXPECT_EQ(result, "CruelWorld"); result = absl::StrCat(stdstrs[1], " ", stdstrs[2]); EXPECT_EQ(result, "std::Cruel std::World"); result = absl::StrCat(strs[0], ", ", pieces[2]); EXPECT_EQ(result, "Hello, World"); result = absl::StrCat(strs[0], ", ", strs[1], " ", strs[2], "!"); EXPECT_EQ(result, "Hello, Cruel World!"); result = absl::StrCat(pieces[0], ", ", pieces[1], " ", pieces[2]); EXPECT_EQ(result, "Hello, Cruel World"); result = absl::StrCat(c_strs[0], ", ", c_strs[1], " ", c_strs[2]); EXPECT_EQ(result, "Hello, Cruel World"); result = absl::StrCat("ASCII ", i32s[0], ", ", i32s[1], " ", i32s[2], "!"); EXPECT_EQ(result, "ASCII 72, 67 87!"); result = absl::StrCat(ui64s[0], ", ", ui64s[1], "!"); EXPECT_EQ(result, "12345678910, 10987654321!"); std::string one = "1"; // Actually, it's the size of this string that we want; a // 64-bit build distinguishes between size_t and uint64_t, // even though they're both unsigned 64-bit values. result = absl::StrCat("And a ", one.size(), " and a ", &result[2] - &result[0], " and a ", one, " 2 3 4", "!"); EXPECT_EQ(result, "And a 1 and a 2 and a 1 2 3 4!"); // result = absl::StrCat("Single chars won't compile", '!'); // result = absl::StrCat("Neither will nullptrs", nullptr); result = absl::StrCat("To output a char by ASCII/numeric value, use +: ", '!' + 0); EXPECT_EQ(result, "To output a char by ASCII/numeric value, use +: 33"); float f = 100000.5; result = absl::StrCat("A hundred K and a half is ", absl::SixDigits(f)); EXPECT_EQ(result, "A hundred K and a half is 100000"); f = 100001.5; result = absl::StrCat("A hundred K and one and a half is ", absl::SixDigits(f)); EXPECT_EQ(result, "A hundred K and one and a half is 100002"); double d = 100000.5; d *= d; result = absl::StrCat("A hundred K and a half squared is ", absl::SixDigits(d)); EXPECT_EQ(result, "A hundred K and a half squared is 1.00001e+10"); result = absl::StrCat(1, 2, 333, 4444, 55555, 666666, 7777777, 88888888, 999999999); EXPECT_EQ(result, "12333444455555666666777777788888888999999999"); } TEST(StrCat, CornerCases) { std::string result; result = absl::StrCat(""); // NOLINT EXPECT_EQ(result, ""); result = absl::StrCat("", ""); EXPECT_EQ(result, ""); result = absl::StrCat("", "", ""); EXPECT_EQ(result, ""); result = absl::StrCat("", "", "", ""); EXPECT_EQ(result, ""); result = absl::StrCat("", "", "", "", ""); EXPECT_EQ(result, ""); } TEST(StrCat, NullConstCharPtr) { const char* null = nullptr; EXPECT_EQ(absl::StrCat("mon", null, "key"), "monkey"); } // A minimal allocator that uses malloc(). template struct Mallocator { typedef T value_type; typedef size_t size_type; typedef ptrdiff_t difference_type; typedef T* pointer; typedef const T* const_pointer; typedef T& reference; typedef const T& const_reference; size_type max_size() const { return size_t(std::numeric_limits::max()) / sizeof(value_type); } template struct rebind { typedef Mallocator other; }; Mallocator() = default; template Mallocator(const Mallocator&) {} // NOLINT(runtime/explicit) T* allocate(size_t n) { return static_cast(std::malloc(n * sizeof(T))); } void deallocate(T* p, size_t) { std::free(p); } }; template bool operator==(const Mallocator&, const Mallocator&) { return true; } template bool operator!=(const Mallocator&, const Mallocator&) { return false; } TEST(StrCat, CustomAllocator) { using mstring = std::basic_string, Mallocator>; const mstring str1("PARACHUTE OFF A BLIMP INTO MOSCONE!!"); const mstring str2("Read this book about coffee tables"); std::string result = absl::StrCat(str1, str2); EXPECT_EQ(result, "PARACHUTE OFF A BLIMP INTO MOSCONE!!" "Read this book about coffee tables"); } TEST(StrCat, MaxArgs) { std::string result; // Test 10 up to 26 arguments, the old maximum result = absl::StrCat(1, 2, 3, 4, 5, 6, 7, 8, 9, "a"); EXPECT_EQ(result, "123456789a"); result = absl::StrCat(1, 2, 3, 4, 5, 6, 7, 8, 9, "a", "b"); EXPECT_EQ(result, "123456789ab"); result = absl::StrCat(1, 2, 3, 4, 5, 6, 7, 8, 9, "a", "b", "c"); EXPECT_EQ(result, "123456789abc"); result = absl::StrCat(1, 2, 3, 4, 5, 6, 7, 8, 9, "a", "b", "c", "d"); EXPECT_EQ(result, "123456789abcd"); result = absl::StrCat(1, 2, 3, 4, 5, 6, 7, 8, 9, "a", "b", "c", "d", "e"); EXPECT_EQ(result, "123456789abcde"); result = absl::StrCat(1, 2, 3, 4, 5, 6, 7, 8, 9, "a", "b", "c", "d", "e", "f"); EXPECT_EQ(result, "123456789abcdef"); result = absl::StrCat(1, 2, 3, 4, 5, 6, 7, 8, 9, "a", "b", "c", "d", "e", "f", "g"); EXPECT_EQ(result, "123456789abcdefg"); result = absl::StrCat(1, 2, 3, 4, 5, 6, 7, 8, 9, "a", "b", "c", "d", "e", "f", "g", "h"); EXPECT_EQ(result, "123456789abcdefgh"); result = absl::StrCat(1, 2, 3, 4, 5, 6, 7, 8, 9, "a", "b", "c", "d", "e", "f", "g", "h", "i"); EXPECT_EQ(result, "123456789abcdefghi"); result = absl::StrCat(1, 2, 3, 4, 5, 6, 7, 8, 9, "a", "b", "c", "d", "e", "f", "g", "h", "i", "j"); EXPECT_EQ(result, "123456789abcdefghij"); result = absl::StrCat(1, 2, 3, 4, 5, 6, 7, 8, 9, "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k"); EXPECT_EQ(result, "123456789abcdefghijk"); result = absl::StrCat(1, 2, 3, 4, 5, 6, 7, 8, 9, "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l"); EXPECT_EQ(result, "123456789abcdefghijkl"); result = absl::StrCat(1, 2, 3, 4, 5, 6, 7, 8, 9, "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m"); EXPECT_EQ(result, "123456789abcdefghijklm"); result = absl::StrCat(1, 2, 3, 4, 5, 6, 7, 8, 9, "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n"); EXPECT_EQ(result, "123456789abcdefghijklmn"); result = absl::StrCat(1, 2, 3, 4, 5, 6, 7, 8, 9, "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o"); EXPECT_EQ(result, "123456789abcdefghijklmno"); result = absl::StrCat(1, 2, 3, 4, 5, 6, 7, 8, 9, "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p"); EXPECT_EQ(result, "123456789abcdefghijklmnop"); result = absl::StrCat(1, 2, 3, 4, 5, 6, 7, 8, 9, "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q"); EXPECT_EQ(result, "123456789abcdefghijklmnopq"); // No limit thanks to C++11's variadic templates result = absl::StrCat( 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z", "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z"); EXPECT_EQ(result, "12345678910abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"); } TEST(StrAppend, Basics) { std::string result = "existing text"; std::string strs[] = {"Hello", "Cruel", "World"}; std::string stdstrs[] = { "std::Hello", "std::Cruel", "std::World" }; absl::string_view pieces[] = {"Hello", "Cruel", "World"}; const char* c_strs[] = { "Hello", "Cruel", "World" }; int32_t i32s[] = {'H', 'C', 'W'}; uint64_t ui64s[] = {12345678910LL, 10987654321LL}; std::string::size_type old_size = result.size(); absl::StrAppend(&result); EXPECT_EQ(result.size(), old_size); old_size = result.size(); absl::StrAppend(&result, strs[0]); EXPECT_EQ(result.substr(old_size), "Hello"); old_size = result.size(); absl::StrAppend(&result, strs[1], pieces[2]); EXPECT_EQ(result.substr(old_size), "CruelWorld"); old_size = result.size(); absl::StrAppend(&result, stdstrs[0], ", ", pieces[2]); EXPECT_EQ(result.substr(old_size), "std::Hello, World"); old_size = result.size(); absl::StrAppend(&result, strs[0], ", ", stdstrs[1], " ", strs[2], "!"); EXPECT_EQ(result.substr(old_size), "Hello, std::Cruel World!"); old_size = result.size(); absl::StrAppend(&result, pieces[0], ", ", pieces[1], " ", pieces[2]); EXPECT_EQ(result.substr(old_size), "Hello, Cruel World"); old_size = result.size(); absl::StrAppend(&result, c_strs[0], ", ", c_strs[1], " ", c_strs[2]); EXPECT_EQ(result.substr(old_size), "Hello, Cruel World"); old_size = result.size(); absl::StrAppend(&result, "ASCII ", i32s[0], ", ", i32s[1], " ", i32s[2], "!"); EXPECT_EQ(result.substr(old_size), "ASCII 72, 67 87!"); old_size = result.size(); absl::StrAppend(&result, ui64s[0], ", ", ui64s[1], "!"); EXPECT_EQ(result.substr(old_size), "12345678910, 10987654321!"); std::string one = "1"; // Actually, it's the size of this string that we want; a // 64-bit build distinguishes between size_t and uint64_t, // even though they're both unsigned 64-bit values. old_size = result.size(); absl::StrAppend(&result, "And a ", one.size(), " and a ", &result[2] - &result[0], " and a ", one, " 2 3 4", "!"); EXPECT_EQ(result.substr(old_size), "And a 1 and a 2 and a 1 2 3 4!"); // result = absl::StrCat("Single chars won't compile", '!'); // result = absl::StrCat("Neither will nullptrs", nullptr); old_size = result.size(); absl::StrAppend(&result, "To output a char by ASCII/numeric value, use +: ", '!' + 0); EXPECT_EQ(result.substr(old_size), "To output a char by ASCII/numeric value, use +: 33"); // Test 9 arguments, the old maximum old_size = result.size(); absl::StrAppend(&result, 1, 22, 333, 4444, 55555, 666666, 7777777, 88888888, 9); EXPECT_EQ(result.substr(old_size), "1223334444555556666667777777888888889"); // No limit thanks to C++11's variadic templates old_size = result.size(); absl::StrAppend( &result, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, // "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", // "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z", // "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", // "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z", // "No limit thanks to C++11's variadic templates"); EXPECT_EQ(result.substr(old_size), "12345678910abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ" "No limit thanks to C++11's variadic templates"); } TEST(StrCat, VectorBoolReferenceTypes) { std::vector v; v.push_back(true); v.push_back(false); std::vector const& cv = v; // Test that vector::reference and vector::const_reference // are handled as if the were really bool types and not the proxy types // they really are. std::string result = absl::StrCat(v[0], v[1], cv[0], cv[1]); // NOLINT EXPECT_EQ(result, "1010"); } // Passing nullptr to memcpy is undefined behavior and this test // provides coverage of codepaths that handle empty strings with nullptrs. TEST(StrCat, AvoidsMemcpyWithNullptr) { EXPECT_EQ(absl::StrCat(42, absl::string_view{}), "42"); // Cover CatPieces code. EXPECT_EQ(absl::StrCat(1, 2, 3, 4, 5, absl::string_view{}), "12345"); // Cover AppendPieces. std::string result; absl::StrAppend(&result, 1, 2, 3, 4, 5, absl::string_view{}); EXPECT_EQ(result, "12345"); } #if GTEST_HAS_DEATH_TEST TEST(StrAppend, Death) { std::string s = "self"; // on linux it's "assertion", on mac it's "Assertion", // on chromiumos it's "Assertion ... failed". ABSL_EXPECT_DEBUG_DEATH(absl::StrAppend(&s, s.c_str() + 1), "ssertion.*failed"); ABSL_EXPECT_DEBUG_DEATH(absl::StrAppend(&s, s), "ssertion.*failed"); } #endif // GTEST_HAS_DEATH_TEST TEST(StrAppend, CornerCases) { std::string result; absl::StrAppend(&result, ""); EXPECT_EQ(result, ""); absl::StrAppend(&result, "", ""); EXPECT_EQ(result, ""); absl::StrAppend(&result, "", "", ""); EXPECT_EQ(result, ""); absl::StrAppend(&result, "", "", "", ""); EXPECT_EQ(result, ""); absl::StrAppend(&result, "", "", "", "", ""); EXPECT_EQ(result, ""); } TEST(StrAppend, CornerCasesNonEmptyAppend) { for (std::string result : {"hello", "a string too long to fit in the SSO"}) { const std::string expected = result; absl::StrAppend(&result, ""); EXPECT_EQ(result, expected); absl::StrAppend(&result, "", ""); EXPECT_EQ(result, expected); absl::StrAppend(&result, "", "", ""); EXPECT_EQ(result, expected); absl::StrAppend(&result, "", "", "", ""); EXPECT_EQ(result, expected); absl::StrAppend(&result, "", "", "", "", ""); EXPECT_EQ(result, expected); } } template void CheckHex(IntType v, const char* nopad_format, const char* zeropad_format, const char* spacepad_format) { char expected[256]; std::string actual = absl::StrCat(absl::Hex(v, absl::kNoPad)); snprintf(expected, sizeof(expected), nopad_format, v); EXPECT_EQ(expected, actual) << " decimal value " << v; for (int spec = absl::kZeroPad2; spec <= absl::kZeroPad20; ++spec) { std::string actual = absl::StrCat(absl::Hex(v, static_cast(spec))); snprintf(expected, sizeof(expected), zeropad_format, spec - absl::kZeroPad2 + 2, v); EXPECT_EQ(expected, actual) << " decimal value " << v; } for (int spec = absl::kSpacePad2; spec <= absl::kSpacePad20; ++spec) { std::string actual = absl::StrCat(absl::Hex(v, static_cast(spec))); snprintf(expected, sizeof(expected), spacepad_format, spec - absl::kSpacePad2 + 2, v); EXPECT_EQ(expected, actual) << " decimal value " << v; } } template void CheckDec(IntType v, const char* nopad_format, const char* zeropad_format, const char* spacepad_format) { char expected[256]; std::string actual = absl::StrCat(absl::Dec(v, absl::kNoPad)); snprintf(expected, sizeof(expected), nopad_format, v); EXPECT_EQ(expected, actual) << " decimal value " << v; for (int spec = absl::kZeroPad2; spec <= absl::kZeroPad20; ++spec) { std::string actual = absl::StrCat(absl::Dec(v, static_cast(spec))); snprintf(expected, sizeof(expected), zeropad_format, spec - absl::kZeroPad2 + 2, v); EXPECT_EQ(expected, actual) << " decimal value " << v << " format '" << zeropad_format << "' digits " << (spec - absl::kZeroPad2 + 2); } for (int spec = absl::kSpacePad2; spec <= absl::kSpacePad20; ++spec) { std::string actual = absl::StrCat(absl::Dec(v, static_cast(spec))); snprintf(expected, sizeof(expected), spacepad_format, spec - absl::kSpacePad2 + 2, v); EXPECT_EQ(expected, actual) << " decimal value " << v << " format '" << spacepad_format << "' digits " << (spec - absl::kSpacePad2 + 2); } } void CheckHexDec64(uint64_t v) { unsigned long long ullv = v; // NOLINT(runtime/int) CheckHex(ullv, "%llx", "%0*llx", "%*llx"); CheckDec(ullv, "%llu", "%0*llu", "%*llu"); long long llv = static_cast(ullv); // NOLINT(runtime/int) CheckDec(llv, "%lld", "%0*lld", "%*lld"); if (sizeof(v) == sizeof(&v)) { auto uintptr = static_cast(v); void* ptr = reinterpret_cast(uintptr); CheckHex(ptr, "%llx", "%0*llx", "%*llx"); } } void CheckHexDec32(uint32_t uv) { CheckHex(uv, "%x", "%0*x", "%*x"); CheckDec(uv, "%u", "%0*u", "%*u"); int32_t v = static_cast(uv); CheckDec(v, "%d", "%0*d", "%*d"); if (sizeof(v) == sizeof(&v)) { auto uintptr = static_cast(v); void* ptr = reinterpret_cast(uintptr); CheckHex(ptr, "%x", "%0*x", "%*x"); } } void CheckAll(uint64_t v) { CheckHexDec64(v); CheckHexDec32(static_cast(v)); } void TestFastPrints() { // Test all small ints; there aren't many and they're common. for (int i = 0; i < 10000; i++) { CheckAll(i); } CheckAll(std::numeric_limits::max()); CheckAll(std::numeric_limits::max() - 1); CheckAll(std::numeric_limits::min()); CheckAll(std::numeric_limits::min() + 1); CheckAll(std::numeric_limits::max()); CheckAll(std::numeric_limits::max() - 1); CheckAll(std::numeric_limits::min()); CheckAll(std::numeric_limits::min() + 1); CheckAll(999999999); // fits in 32 bits CheckAll(1000000000); // fits in 32 bits CheckAll(9999999999); // doesn't fit in 32 bits CheckAll(10000000000); // doesn't fit in 32 bits CheckAll(999999999999999999); // fits in signed 64-bit CheckAll(9999999999999999999u); // fits in unsigned 64-bit, but not signed. CheckAll(1000000000000000000); // fits in signed 64-bit CheckAll(10000000000000000000u); // fits in unsigned 64-bit, but not signed. CheckAll(999999999876543210); // check all decimal digits, signed CheckAll(9999999999876543210u); // check all decimal digits, unsigned. CheckAll(0x123456789abcdef0); // check all hex digits CheckAll(0x12345678); int8_t minus_one_8bit = -1; EXPECT_EQ("ff", absl::StrCat(absl::Hex(minus_one_8bit))); int16_t minus_one_16bit = -1; EXPECT_EQ("ffff", absl::StrCat(absl::Hex(minus_one_16bit))); } TEST(Numbers, TestFunctionsMovedOverFromNumbersMain) { TestFastPrints(); } struct PointStringify { template friend void AbslStringify(FormatSink& sink, const PointStringify& p) { sink.Append("("); sink.Append(absl::StrCat(p.x)); sink.Append(", "); sink.Append(absl::StrCat(p.y)); sink.Append(")"); } double x = 10.0; double y = 20.0; }; TEST(StrCat, AbslStringifyExample) { PointStringify p; EXPECT_EQ(absl::StrCat(p), "(10, 20)"); EXPECT_EQ(absl::StrCat("a ", p, " z"), "a (10, 20) z"); } struct PointStringifyUsingFormat { template friend void AbslStringify(FormatSink& sink, const PointStringifyUsingFormat& p) { absl::Format(&sink, "(%g, %g)", p.x, p.y); } double x = 10.0; double y = 20.0; }; TEST(StrCat, AbslStringifyExampleUsingFormat) { PointStringifyUsingFormat p; EXPECT_EQ(absl::StrCat(p), "(10, 20)"); EXPECT_EQ(absl::StrCat("a ", p, " z"), "a (10, 20) z"); } enum class EnumWithStringify { Many = 0, Choices = 1 }; template void AbslStringify(Sink& sink, EnumWithStringify e) { absl::Format(&sink, "%s", e == EnumWithStringify::Many ? "Many" : "Choices"); } TEST(StrCat, AbslStringifyWithEnum) { const auto e = EnumWithStringify::Choices; EXPECT_EQ(absl::StrCat(e), "Choices"); } } // namespace