[libc] Support StringView equality tests

[michaelrj]

Summary

Previously, the integer_to_string tests used EXPECT_TRUE(.equals)
which doesn't have useful error messages. Now they properly check
equality with the EXPECT_EQ macro, which allows for comparing the
strings more naturally.

[sivachandra]

LGTM but will this cause problems to FuchsiaTest: https://github.com/llvm/llvm-project/blob/main/libc/utils/UnitTest/FuchsiaTest.h

[abrachet]

In D131300#3708985, @sivachandra wrote:

LGTM but will this cause problems to FuchsiaTest: https://github.com/llvm/llvm-project/blob/main/libc/utils/UnitTest/FuchsiaTest.h

This will be fine there as long as __llvm_libc::cpp::StringView has an operator==. Though as a drive by comment here, I think the better way to compare StringView's would be to make sure they have an operator const char *() and just use EXPECT_STREQ

[sivachandra]

In D131300#3710101, @abrachet wrote:

In D131300#3708985, @sivachandra wrote:

LGTM but will this cause problems to FuchsiaTest: https://github.com/llvm/llvm-project/blob/main/libc/utils/UnitTest/FuchsiaTest.h

This will be fine there as long as __llvm_libc::cpp::StringView has an operator==. Though as a drive by comment here, I think the better way to compare StringView's would be to make sure they have an operator const char *() and just use EXPECT_STREQ

I don't think StringView data is necessarily null-terminated?

[abrachet]

In D131300#3710120, @sivachandra wrote:

In D131300#3710101, @abrachet wrote:

In D131300#3708985, @sivachandra wrote:

LGTM but will this cause problems to FuchsiaTest: https://github.com/llvm/llvm-project/blob/main/libc/utils/UnitTest/FuchsiaTest.h

This will be fine there as long as __llvm_libc::cpp::StringView has an operator==. Though as a drive by comment here, I think the better way to compare StringView's would be to make sure they have an operator const char *() and just use EXPECT_STREQ

I don't think StringView data is necessarily null-terminated?

Ah thats right, sorry about the noise

[michaelrj]

I would guess the potential problem would be in describeValue since fuchsia might not know how to convert a StringView into a std::string for display

[sivachandra]

In D131300#3710288, @michaelrj wrote:

I would guess the potential problem would be in describeValue since fuchsia might not know how to convert a StringView into a std::string for display

Fuchcia does not use the LibcTest so describeValue does not come into play there.

[michaelrj]

rebase before landing

libc/test/src/__support/integer_to_string_test.cpp

 #include "utils/UnitTest/Test.h"
 
 #include "limits.h"
 
 using __llvm_libc::integer_to_string;
 using __llvm_libc::cpp::StringView;
 
 TEST(LlvmLibcIntegerToStringTest, UINT8) {
-  EXPECT_TRUE(integer_to_string(uint8_t(0)).str().equals(StringView("0")));
-  EXPECT_TRUE(integer_to_string(uint8_t(1)).str().equals(StringView("1")));
-  EXPECT_TRUE(integer_to_string(uint8_t(12)).str().equals(StringView("12")));
-  EXPECT_TRUE(integer_to_string(uint8_t(123)).str().equals(StringView("123")));
-  EXPECT_TRUE(
-      integer_to_string(uint8_t(UINT8_MAX)).str().equals(StringView("255")));
-  EXPECT_TRUE(integer_to_string(uint8_t(-1)).str().equals(StringView("255")));
+  EXPECT_EQ(integer_to_string(uint8_t(0)).str(), (StringView("0")));
+  EXPECT_EQ(integer_to_string(uint8_t(1)).str(), (StringView("1")));
+  EXPECT_EQ(integer_to_string(uint8_t(12)).str(), (StringView("12")));
+  EXPECT_EQ(integer_to_string(uint8_t(123)).str(), (StringView("123")));
+  EXPECT_EQ(integer_to_string(uint8_t(UINT8_MAX)).str(), (StringView("255")));
+  EXPECT_EQ(integer_to_string(uint8_t(-1)).str(), (StringView("255")));
 }
 
 TEST(LlvmLibcIntegerToStringTest, INT8) {
-  EXPECT_TRUE(integer_to_string(int8_t(0)).str().equals(StringView("0")));
-  EXPECT_TRUE(integer_to_string(int8_t(1)).str().equals(StringView("1")));
-  EXPECT_TRUE(integer_to_string(int8_t(12)).str().equals(StringView("12")));
-  EXPECT_TRUE(integer_to_string(int8_t(123)).str().equals(StringView("123")));
-  EXPECT_TRUE(integer_to_string(int8_t(-12)).str().equals(StringView("-12")));
-  EXPECT_TRUE(integer_to_string(int8_t(-123)).str().equals(StringView("-123")));
-  EXPECT_TRUE(
-      integer_to_string(int8_t(INT8_MAX)).str().equals(StringView("127")));
-  EXPECT_TRUE(
-      integer_to_string(int8_t(INT8_MIN)).str().equals(StringView("-128")));
+  EXPECT_EQ(integer_to_string(int8_t(0)).str(), (StringView("0")));
+  EXPECT_EQ(integer_to_string(int8_t(1)).str(), (StringView("1")));
+  EXPECT_EQ(integer_to_string(int8_t(12)).str(), (StringView("12")));
+  EXPECT_EQ(integer_to_string(int8_t(123)).str(), (StringView("123")));
+  EXPECT_EQ(integer_to_string(int8_t(-12)).str(), (StringView("-12")));
+  EXPECT_EQ(integer_to_string(int8_t(-123)).str(), (StringView("-123")));
+  EXPECT_EQ(integer_to_string(int8_t(INT8_MAX)).str(), (StringView("127")));
+  EXPECT_EQ(integer_to_string(int8_t(INT8_MIN)).str(), (StringView("-128")));
 }
 
 TEST(LlvmLibcIntegerToStringTest, UINT16) {
-  EXPECT_TRUE(integer_to_string(uint16_t(0)).str().equals(StringView("0")));
-  EXPECT_TRUE(integer_to_string(uint16_t(1)).str().equals(StringView("1")));
-  EXPECT_TRUE(integer_to_string(uint16_t(12)).str().equals(StringView("12")));
-  EXPECT_TRUE(integer_to_string(uint16_t(123)).str().equals(StringView("123")));
-  EXPECT_TRUE(
-      integer_to_string(uint16_t(1234)).str().equals(StringView("1234")));
-  EXPECT_TRUE(
-      integer_to_string(uint16_t(12345)).str().equals(StringView("12345")));
-  EXPECT_TRUE(integer_to_string(uint16_t(UINT16_MAX))
-                  .str()
-                  .equals(StringView("65535")));
-  EXPECT_TRUE(
-      integer_to_string(uint16_t(-1)).str().equals(StringView("65535")));
+  EXPECT_EQ(integer_to_string(uint16_t(0)).str(), (StringView("0")));
+  EXPECT_EQ(integer_to_string(uint16_t(1)).str(), (StringView("1")));
+  EXPECT_EQ(integer_to_string(uint16_t(12)).str(), (StringView("12")));
+  EXPECT_EQ(integer_to_string(uint16_t(123)).str(), (StringView("123")));
+  EXPECT_EQ(integer_to_string(uint16_t(1234)).str(), (StringView("1234")));
+  EXPECT_EQ(integer_to_string(uint16_t(12345)).str(), (StringView("12345")));
+  EXPECT_EQ(integer_to_string(uint16_t(UINT16_MAX)).str(),
+            (StringView("65535")));
+  EXPECT_EQ(integer_to_string(uint16_t(-1)).str(), (StringView("65535")));
 }
 
 TEST(LlvmLibcIntegerToStringTest, INT16) {
-  EXPECT_TRUE(integer_to_string(int16_t(0)).str().equals(StringView("0")));
-  EXPECT_TRUE(integer_to_string(int16_t(1)).str().equals(StringView("1")));
-  EXPECT_TRUE(integer_to_string(int16_t(12)).str().equals(StringView("12")));
-  EXPECT_TRUE(integer_to_string(int16_t(123)).str().equals(StringView("123")));
-  EXPECT_TRUE(
-      integer_to_string(int16_t(1234)).str().equals(StringView("1234")));
-  EXPECT_TRUE(
-      integer_to_string(int16_t(12345)).str().equals(StringView("12345")));
-  EXPECT_TRUE(integer_to_string(int16_t(-1)).str().equals(StringView("-1")));
-  EXPECT_TRUE(integer_to_string(int16_t(-12)).str().equals(StringView("-12")));
-  EXPECT_TRUE(
-      integer_to_string(int16_t(-123)).str().equals(StringView("-123")));
-  EXPECT_TRUE(
-      integer_to_string(int16_t(-1234)).str().equals(StringView("-1234")));
-  EXPECT_TRUE(
-      integer_to_string(int16_t(-12345)).str().equals(StringView("-12345")));
-  EXPECT_TRUE(
-      integer_to_string(int16_t(INT16_MAX)).str().equals(StringView("32767")));
-  EXPECT_TRUE(
-      integer_to_string(int16_t(INT16_MIN)).str().equals(StringView("-32768")));
+  EXPECT_EQ(integer_to_string(int16_t(0)).str(), (StringView("0")));
+  EXPECT_EQ(integer_to_string(int16_t(1)).str(), (StringView("1")));
+  EXPECT_EQ(integer_to_string(int16_t(12)).str(), (StringView("12")));
+  EXPECT_EQ(integer_to_string(int16_t(123)).str(), (StringView("123")));
+  EXPECT_EQ(integer_to_string(int16_t(1234)).str(), (StringView("1234")));
+  EXPECT_EQ(integer_to_string(int16_t(12345)).str(), (StringView("12345")));
+  EXPECT_EQ(integer_to_string(int16_t(-1)).str(), (StringView("-1")));
+  EXPECT_EQ(integer_to_string(int16_t(-12)).str(), (StringView("-12")));
+  EXPECT_EQ(integer_to_string(int16_t(-123)).str(), (StringView("-123")));
+  EXPECT_EQ(integer_to_string(int16_t(-1234)).str(), (StringView("-1234")));
+  EXPECT_EQ(integer_to_string(int16_t(-12345)).str(), (StringView("-12345")));
+  EXPECT_EQ(integer_to_string(int16_t(INT16_MAX)).str(), (StringView("32767")));
+  EXPECT_EQ(integer_to_string(int16_t(INT16_MIN)).str(),
+            (StringView("-32768")));
 }
 
 TEST(LlvmLibcIntegerToStringTest, UINT32) {
-  EXPECT_TRUE(integer_to_string(uint32_t(0)).str().equals(StringView("0")));
-  EXPECT_TRUE(integer_to_string(uint32_t(1)).str().equals(StringView("1")));
-  EXPECT_TRUE(integer_to_string(uint32_t(12)).str().equals(StringView("12")));
-  EXPECT_TRUE(integer_to_string(uint32_t(123)).str().equals(StringView("123")));
-  EXPECT_TRUE(
-      integer_to_string(uint32_t(1234)).str().equals(StringView("1234")));
-  EXPECT_TRUE(
-      integer_to_string(uint32_t(12345)).str().equals(StringView("12345")));
-  EXPECT_TRUE(
-      integer_to_string(uint32_t(123456)).str().equals(StringView("123456")));
-  EXPECT_TRUE(
-      integer_to_string(uint32_t(1234567)).str().equals(StringView("1234567")));
-  EXPECT_TRUE(integer_to_string(uint32_t(12345678))
-                  .str()
-                  .equals(StringView("12345678")));
-  EXPECT_TRUE(integer_to_string(uint32_t(123456789))
-                  .str()
-                  .equals(StringView("123456789")));
-  EXPECT_TRUE(integer_to_string(uint32_t(1234567890))
-                  .str()
-                  .equals(StringView("1234567890")));
-  EXPECT_TRUE(integer_to_string(uint32_t(UINT32_MAX))
-                  .str()
-                  .equals(StringView("4294967295")));
-  EXPECT_TRUE(
-      integer_to_string(uint32_t(-1)).str().equals(StringView("4294967295")));
+  EXPECT_EQ(integer_to_string(uint32_t(0)).str(), (StringView("0")));
+  EXPECT_EQ(integer_to_string(uint32_t(1)).str(), (StringView("1")));
+  EXPECT_EQ(integer_to_string(uint32_t(12)).str(), (StringView("12")));
+  EXPECT_EQ(integer_to_string(uint32_t(123)).str(), (StringView("123")));
+  EXPECT_EQ(integer_to_string(uint32_t(1234)).str(), (StringView("1234")));
+  EXPECT_EQ(integer_to_string(uint32_t(12345)).str(), (StringView("12345")));
+  EXPECT_EQ(integer_to_string(uint32_t(123456)).str(), (StringView("123456")));
+  EXPECT_EQ(integer_to_string(uint32_t(1234567)).str(),
+            (StringView("1234567")));
+  EXPECT_EQ(integer_to_string(uint32_t(12345678)).str(),
+            (StringView("12345678")));
+  EXPECT_EQ(integer_to_string(uint32_t(123456789)).str(),
+            (StringView("123456789")));
+  EXPECT_EQ(integer_to_string(uint32_t(1234567890)).str(),
+            (StringView("1234567890")));
+  EXPECT_EQ(integer_to_string(uint32_t(UINT32_MAX)).str(),
+            (StringView("4294967295")));
+  EXPECT_EQ(integer_to_string(uint32_t(-1)).str(), (StringView("4294967295")));
 }
 
 TEST(LlvmLibcIntegerToStringTest, INT32) {
-  EXPECT_TRUE(integer_to_string(int32_t(0)).str().equals(StringView("0")));
-  EXPECT_TRUE(integer_to_string(int32_t(1)).str().equals(StringView("1")));
-  EXPECT_TRUE(integer_to_string(int32_t(12)).str().equals(StringView("12")));
-  EXPECT_TRUE(integer_to_string(int32_t(123)).str().equals(StringView("123")));
-  EXPECT_TRUE(
-      integer_to_string(int32_t(1234)).str().equals(StringView("1234")));
-  EXPECT_TRUE(
-      integer_to_string(int32_t(12345)).str().equals(StringView("12345")));
-  EXPECT_TRUE(
-      integer_to_string(int32_t(123456)).str().equals(StringView("123456")));
-  EXPECT_TRUE(
-      integer_to_string(int32_t(1234567)).str().equals(StringView("1234567")));
-  EXPECT_TRUE(integer_to_string(int32_t(12345678))
-                  .str()
-                  .equals(StringView("12345678")));
-  EXPECT_TRUE(integer_to_string(int32_t(123456789))
-                  .str()
-                  .equals(StringView("123456789")));
-  EXPECT_TRUE(integer_to_string(int32_t(1234567890))
-                  .str()
-                  .equals(StringView("1234567890")));
-  EXPECT_TRUE(integer_to_string(int32_t(-1)).str().equals(StringView("-1")));
-  EXPECT_TRUE(integer_to_string(int32_t(-12)).str().equals(StringView("-12")));
-  EXPECT_TRUE(
-      integer_to_string(int32_t(-123)).str().equals(StringView("-123")));
-  EXPECT_TRUE(
-      integer_to_string(int32_t(-1234)).str().equals(StringView("-1234")));
-  EXPECT_TRUE(
-      integer_to_string(int32_t(-12345)).str().equals(StringView("-12345")));
-  EXPECT_TRUE(
-      integer_to_string(int32_t(-123456)).str().equals(StringView("-123456")));
-  EXPECT_TRUE(integer_to_string(int32_t(-1234567))
-                  .str()
-                  .equals(StringView("-1234567")));
-  EXPECT_TRUE(integer_to_string(int32_t(-12345678))
-                  .str()
-                  .equals(StringView("-12345678")));
-  EXPECT_TRUE(integer_to_string(int32_t(-123456789))
-                  .str()
-                  .equals(StringView("-123456789")));
-  EXPECT_TRUE(integer_to_string(int32_t(-1234567890))
-                  .str()
-                  .equals(StringView("-1234567890")));
-  EXPECT_TRUE(integer_to_string(int32_t(INT32_MAX))
-                  .str()
-                  .equals(StringView("2147483647")));
-  EXPECT_TRUE(integer_to_string(int32_t(INT32_MIN))
-                  .str()
-                  .equals(StringView("-2147483648")));
+  EXPECT_EQ(integer_to_string(int32_t(0)).str(), (StringView("0")));
+  EXPECT_EQ(integer_to_string(int32_t(1)).str(), (StringView("1")));
+  EXPECT_EQ(integer_to_string(int32_t(12)).str(), (StringView("12")));
+  EXPECT_EQ(integer_to_string(int32_t(123)).str(), (StringView("123")));
+  EXPECT_EQ(integer_to_string(int32_t(1234)).str(), (StringView("1234")));
+  EXPECT_EQ(integer_to_string(int32_t(12345)).str(), (StringView("12345")));
+  EXPECT_EQ(integer_to_string(int32_t(123456)).str(), (StringView("123456")));
+  EXPECT_EQ(integer_to_string(int32_t(1234567)).str(), (StringView("1234567")));
+  EXPECT_EQ(integer_to_string(int32_t(12345678)).str(),
+            (StringView("12345678")));
+  EXPECT_EQ(integer_to_string(int32_t(123456789)).str(),
+            (StringView("123456789")));
+  EXPECT_EQ(integer_to_string(int32_t(1234567890)).str(),
+            (StringView("1234567890")));
+  EXPECT_EQ(integer_to_string(int32_t(-1)).str(), (StringView("-1")));
+  EXPECT_EQ(integer_to_string(int32_t(-12)).str(), (StringView("-12")));
+  EXPECT_EQ(integer_to_string(int32_t(-123)).str(), (StringView("-123")));
+  EXPECT_EQ(integer_to_string(int32_t(-1234)).str(), (StringView("-1234")));
+  EXPECT_EQ(integer_to_string(int32_t(-12345)).str(), (StringView("-12345")));
+  EXPECT_EQ(integer_to_string(int32_t(-123456)).str(), (StringView("-123456")));
+  EXPECT_EQ(integer_to_string(int32_t(-1234567)).str(),
+            (StringView("-1234567")));
+  EXPECT_EQ(integer_to_string(int32_t(-12345678)).str(),
+            (StringView("-12345678")));
+  EXPECT_EQ(integer_to_string(int32_t(-123456789)).str(),
+            (StringView("-123456789")));
+  EXPECT_EQ(integer_to_string(int32_t(-1234567890)).str(),
+            (StringView("-1234567890")));
+  EXPECT_EQ(integer_to_string(int32_t(INT32_MAX)).str(),
+            (StringView("2147483647")));
+  EXPECT_EQ(integer_to_string(int32_t(INT32_MIN)).str(),
+            (StringView("-2147483648")));
 }
 
 TEST(LlvmLibcIntegerToStringTest, UINT64) {
-  EXPECT_TRUE(integer_to_string(uint64_t(0)).str().equals(StringView("0")));
-  EXPECT_TRUE(integer_to_string(uint64_t(1)).str().equals(StringView("1")));
-  EXPECT_TRUE(integer_to_string(uint64_t(12)).str().equals(StringView("12")));
-  EXPECT_TRUE(integer_to_string(uint64_t(123)).str().equals(StringView("123")));
-  EXPECT_TRUE(
-      integer_to_string(uint64_t(1234)).str().equals(StringView("1234")));
-  EXPECT_TRUE(
-      integer_to_string(uint64_t(12345)).str().equals(StringView("12345")));
-  EXPECT_TRUE(
-      integer_to_string(uint64_t(123456)).str().equals(StringView("123456")));
-  EXPECT_TRUE(
-      integer_to_string(uint64_t(1234567)).str().equals(StringView("1234567")));
-  EXPECT_TRUE(integer_to_string(uint64_t(12345678))
-                  .str()
-                  .equals(StringView("12345678")));
-  EXPECT_TRUE(integer_to_string(uint64_t(123456789))
-                  .str()
-                  .equals(StringView("123456789")));
-  EXPECT_TRUE(integer_to_string(uint64_t(1234567890))
-                  .str()
-                  .equals(StringView("1234567890")));
-  EXPECT_TRUE(integer_to_string(uint64_t(1234567890123456789))
-                  .str()
-                  .equals(StringView("1234567890123456789")));
-  EXPECT_TRUE(integer_to_string(uint64_t(UINT64_MAX))
-                  .str()
-                  .equals(StringView("18446744073709551615")));
-  EXPECT_TRUE(integer_to_string(uint64_t(-1))
-                  .str()
-                  .equals(StringView("18446744073709551615")));
+  EXPECT_EQ(integer_to_string(uint64_t(0)).str(), (StringView("0")));
+  EXPECT_EQ(integer_to_string(uint64_t(1)).str(), (StringView("1")));
+  EXPECT_EQ(integer_to_string(uint64_t(12)).str(), (StringView("12")));
+  EXPECT_EQ(integer_to_string(uint64_t(123)).str(), (StringView("123")));
+  EXPECT_EQ(integer_to_string(uint64_t(1234)).str(), (StringView("1234")));
+  EXPECT_EQ(integer_to_string(uint64_t(12345)).str(), (StringView("12345")));
+  EXPECT_EQ(integer_to_string(uint64_t(123456)).str(), (StringView("123456")));
+  EXPECT_EQ(integer_to_string(uint64_t(1234567)).str(),
+            (StringView("1234567")));
+  EXPECT_EQ(integer_to_string(uint64_t(12345678)).str(),
+            (StringView("12345678")));
+  EXPECT_EQ(integer_to_string(uint64_t(123456789)).str(),
+            (StringView("123456789")));
+  EXPECT_EQ(integer_to_string(uint64_t(1234567890)).str(),
+            (StringView("1234567890")));
+  EXPECT_EQ(integer_to_string(uint64_t(1234567890123456789)).str(),
+            (StringView("1234567890123456789")));
+  EXPECT_EQ(integer_to_string(uint64_t(UINT64_MAX)).str(),
+            (StringView("18446744073709551615")));
+  EXPECT_EQ(integer_to_string(uint64_t(-1)).str(),
+            (StringView("18446744073709551615")));
 }
 
 TEST(LlvmLibcIntegerToStringTest, INT64) {
-  EXPECT_TRUE(integer_to_string(int64_t(0)).str().equals(StringView("0")));
-  EXPECT_TRUE(integer_to_string(int64_t(1)).str().equals(StringView("1")));
-  EXPECT_TRUE(integer_to_string(int64_t(12)).str().equals(StringView("12")));
-  EXPECT_TRUE(integer_to_string(int64_t(123)).str().equals(StringView("123")));
-  EXPECT_TRUE(
-      integer_to_string(int64_t(1234)).str().equals(StringView("1234")));
-  EXPECT_TRUE(
-      integer_to_string(int64_t(12345)).str().equals(StringView("12345")));
-  EXPECT_TRUE(
-      integer_to_string(int64_t(123456)).str().equals(StringView("123456")));
-  EXPECT_TRUE(
-      integer_to_string(int64_t(1234567)).str().equals(StringView("1234567")));
-  EXPECT_TRUE(integer_to_string(int64_t(12345678))
-                  .str()
-                  .equals(StringView("12345678")));
-  EXPECT_TRUE(integer_to_string(int64_t(123456789))
-                  .str()
-                  .equals(StringView("123456789")));
-  EXPECT_TRUE(integer_to_string(int64_t(1234567890))
-                  .str()
-                  .equals(StringView("1234567890")));
-  EXPECT_TRUE(integer_to_string(int64_t(1234567890123456789))
-                  .str()
-                  .equals(StringView("1234567890123456789")));
-  EXPECT_TRUE(integer_to_string(int64_t(-1)).str().equals(StringView("-1")));
-  EXPECT_TRUE(integer_to_string(int64_t(-12)).str().equals(StringView("-12")));
-  EXPECT_TRUE(
-      integer_to_string(int64_t(-123)).str().equals(StringView("-123")));
-  EXPECT_TRUE(
-      integer_to_string(int64_t(-1234)).str().equals(StringView("-1234")));
-  EXPECT_TRUE(
-      integer_to_string(int64_t(-12345)).str().equals(StringView("-12345")));
-  EXPECT_TRUE(
-      integer_to_string(int64_t(-123456)).str().equals(StringView("-123456")));
-  EXPECT_TRUE(integer_to_string(int64_t(-1234567))
-                  .str()
-                  .equals(StringView("-1234567")));
-  EXPECT_TRUE(integer_to_string(int64_t(-12345678))
-                  .str()
-                  .equals(StringView("-12345678")));
-  EXPECT_TRUE(integer_to_string(int64_t(-123456789))
-                  .str()
-                  .equals(StringView("-123456789")));
-  EXPECT_TRUE(integer_to_string(int64_t(-1234567890))
-                  .str()
-                  .equals(StringView("-1234567890")));
-  EXPECT_TRUE(integer_to_string(int64_t(-1234567890123456789))
-                  .str()
-                  .equals(StringView("-1234567890123456789")));
-  EXPECT_TRUE(integer_to_string(int64_t(INT64_MAX))
-                  .str()
-                  .equals(StringView("9223372036854775807")));
-  EXPECT_TRUE(integer_to_string(int64_t(INT64_MIN))
-                  .str()
-                  .equals(StringView("-9223372036854775808")));
+  EXPECT_EQ(integer_to_string(int64_t(0)).str(), (StringView("0")));
+  EXPECT_EQ(integer_to_string(int64_t(1)).str(), (StringView("1")));
+  EXPECT_EQ(integer_to_string(int64_t(12)).str(), (StringView("12")));
+  EXPECT_EQ(integer_to_string(int64_t(123)).str(), (StringView("123")));
+  EXPECT_EQ(integer_to_string(int64_t(1234)).str(), (StringView("1234")));
+  EXPECT_EQ(integer_to_string(int64_t(12345)).str(), (StringView("12345")));
+  EXPECT_EQ(integer_to_string(int64_t(123456)).str(), (StringView("123456")));
+  EXPECT_EQ(integer_to_string(int64_t(1234567)).str(), (StringView("1234567")));
+  EXPECT_EQ(integer_to_string(int64_t(12345678)).str(),
+            (StringView("12345678")));
+  EXPECT_EQ(integer_to_string(int64_t(123456789)).str(),
+            (StringView("123456789")));
+  EXPECT_EQ(integer_to_string(int64_t(1234567890)).str(),
+            (StringView("1234567890")));
+  EXPECT_EQ(integer_to_string(int64_t(1234567890123456789)).str(),
+            (StringView("1234567890123456789")));
+  EXPECT_EQ(integer_to_string(int64_t(-1)).str(), (StringView("-1")));
+  EXPECT_EQ(integer_to_string(int64_t(-12)).str(), (StringView("-12")));
+  EXPECT_EQ(integer_to_string(int64_t(-123)).str(), (StringView("-123")));
+  EXPECT_EQ(integer_to_string(int64_t(-1234)).str(), (StringView("-1234")));
+  EXPECT_EQ(integer_to_string(int64_t(-12345)).str(), (StringView("-12345")));
+  EXPECT_EQ(integer_to_string(int64_t(-123456)).str(), (StringView("-123456")));
+  EXPECT_EQ(integer_to_string(int64_t(-1234567)).str(),
+            (StringView("-1234567")));
+  EXPECT_EQ(integer_to_string(int64_t(-12345678)).str(),
+            (StringView("-12345678")));
+  EXPECT_EQ(integer_to_string(int64_t(-123456789)).str(),
+            (StringView("-123456789")));
+  EXPECT_EQ(integer_to_string(int64_t(-1234567890)).str(),
+            (StringView("-1234567890")));
+  EXPECT_EQ(integer_to_string(int64_t(-1234567890123456789)).str(),
+            (StringView("-1234567890123456789")));
+  EXPECT_EQ(integer_to_string(int64_t(INT64_MAX)).str(),
+            (StringView("9223372036854775807")));
+  EXPECT_EQ(integer_to_string(int64_t(INT64_MIN)).str(),
+            (StringView("-9223372036854775808")));
 }

libc/utils/UnitTest/LibcTest.h

 //===-- Base class for libc unittests ---------------------------*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_LIBC_UTILS_UNITTEST_LIBCTEST_H
 #define LLVM_LIBC_UTILS_UNITTEST_LIBCTEST_H
 
 // This file can only include headers from src/__support/CPP/ or
 // utils/testutils. No other headers should be included.
 
 #include "PlatformDefs.h"
 
+#include "src/__support/CPP/StringView.h"
 #include "src/__support/CPP/type_traits.h"
 #include "utils/testutils/ExecuteFunction.h"
 #include "utils/testutils/StreamWrapper.h"
 
 namespace __llvm_libc {
 namespace testing {
 
 class RunContext;
protected:
   template <typename ValType,
             cpp::enable_if_t<cpp::is_pointer_v<ValType>, ValType> = nullptr>
   bool test(TestCondition Cond, ValType LHS, ValType RHS, const char *LHSStr,
             const char *RHSStr, const char *File, unsigned long Line) {
     return internal::test(Ctx, Cond, (unsigned long long)LHS,
                           (unsigned long long)RHS, LHSStr, RHSStr, File, Line);
   }
 
+  template <typename ValType,
+            cpp::enable_if_t<
+                cpp::is_same_v<ValType, __llvm_libc::cpp::StringView>, int> = 0>
+  bool test(TestCondition Cond, ValType LHS, ValType RHS, const char *LHSStr,
+            const char *RHSStr, const char *File, unsigned long Line) {
+    return internal::test(Ctx, Cond, LHS, RHS, LHSStr, RHSStr, File, Line);
+  }
+
   bool testStrEq(const char *LHS, const char *RHS, const char *LHSStr,
                  const char *RHSStr, const char *File, unsigned long Line);
 
   bool testStrNe(const char *LHS, const char *RHS, const char *LHSStr,
                  const char *RHSStr, const char *File, unsigned long Line);
 
   bool testMatch(bool MatchResult, MatcherBase &Matcher, const char *LHSStr,
                  const char *RHSStr, const char *File, unsigned long Line);

libc/utils/UnitTest/LibcTest.cpp

 //===-- Implementation of the base class for libc unittests----------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #include "LibcTest.h"
 
 #include "src/__support/CPP/UInt128.h"
+#include "src/__support/CPP/StringView.h"
 #include "utils/testutils/ExecuteFunction.h"
 #include <cassert>
 #include <iostream>
 #include <string>
 
 namespace __llvm_libc {
 namespace testing {
 

 // When the value is of integral type, just display it as normal.
 template <typename ValType>
 cpp::enable_if_t<cpp::is_integral_v<ValType>, std::string>
 describeValue(ValType Value) {
   return std::to_string(Value);
 }
 
 std::string describeValue(std::string Value) { return std::string(Value); }
+std::string describeValue(cpp::StringView Value) {
+  return std::string(Value.data(), Value.size());
+}
 
 // When the value is UInt128 or __uint128_t, show its hexadecimal digits.
 // We cannot just use a UInt128 specialization as that resolves to only
 // one type, UInt<128> or __uint128_t. We want both overloads as we want to
 // be able to unittest UInt<128> on platforms where UInt128 resolves to
 // UInt128.
 // TODO(lntue): Investigate why UInt<128> was printed backward, with the lower
 // 64-bits first.
template bool test<__uint128_t>(RunContext *Ctx, TestCondition Cond,
                                 const char *File, unsigned long Line);
 #endif
 
 template bool test<__llvm_libc::cpp::UInt<128>>(
     RunContext *Ctx, TestCondition Cond, __llvm_libc::cpp::UInt<128> LHS,
     __llvm_libc::cpp::UInt<128> RHS, const char *LHSStr, const char *RHSStr,
     const char *File, unsigned long Line);
 
+template bool test<__llvm_libc::cpp::StringView>(RunContext *Ctx, TestCondition Cond,
+                                       __llvm_libc::cpp::StringView LHS,
+                                       __llvm_libc::cpp::StringView RHS,
+                                       const char *LHSStr, const char *RHSStr,
+                                       const char *File, unsigned long Line);
+
 } // namespace internal
 
 bool Test::testStrEq(const char *LHS, const char *RHS, const char *LHSStr,
                      const char *RHSStr, const char *File, unsigned long Line) {
   return internal::test(Ctx, Cond_EQ, LHS ? std::string(LHS) : std::string(),
                         RHS ? std::string(RHS) : std::string(), LHSStr, RHSStr,
                         File, Line);
 }