ladybird/AK/Tests/TestNumberFormat.cpp
Ben Wiederhake 0944f56181 AK: Fix human_readable_size corner cases
In particular: consistent rounding and extreme values.

Before, rounding was something like 'away from 0.999...', which led to
surprising corner cases in which the value was rounded up.

Now, rounding is always 'down'.
This even works for 0xffffffff, and also for 0xffffffffffffffffULL on 64-bit.
2020-08-23 11:24:55 +02:00

163 lines
5.8 KiB
C++

/*
* Copyright (c) 2020, Ben Wiederhake <BenWiederhake.GitHub@gmx.de>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <AK/TestSuite.h>
#include <AK/NumberFormat.h>
/*
* These tests are mostly meant as a rough sanity-check, to see whether
* human_readable_size() crashes or does something very silly. That, however,
* is a fuzzy human term, so these tests have to hard-code the exact expected
* strings.
*
* Please feel free to tweak human_readable_size()'s behavior, and update the
* "expected" strings below.
*/
TEST_CASE(golden_path)
{
EXPECT_EQ(human_readable_size(0), "0 B");
EXPECT_EQ(human_readable_size(123), "123 B");
EXPECT_EQ(human_readable_size(123 * KiB), "123.0 KiB");
EXPECT_EQ(human_readable_size(123 * MiB), "123.0 MiB");
EXPECT_EQ(human_readable_size(2 * GiB), "2.0 GiB");
}
TEST_CASE(border_B_KiB)
{
EXPECT_EQ(human_readable_size(1000), "1000 B");
EXPECT_EQ(human_readable_size(1023), "1023 B");
// KiB = 1024
EXPECT_EQ(human_readable_size(1024), "1.0 KiB");
EXPECT_EQ(human_readable_size(1025), "1.0 KiB");
}
TEST_CASE(fraction_KiB)
{
EXPECT_EQ(human_readable_size(1050), "1.0 KiB");
EXPECT_EQ(human_readable_size(1075), "1.0 KiB");
// 1024 * 1.05 = 1075.2
EXPECT_EQ(human_readable_size(1076), "1.0 KiB");
EXPECT_EQ(human_readable_size(1100), "1.0 KiB");
EXPECT_EQ(human_readable_size(1126), "1.0 KiB");
// 1024 * 1.1 = 1126.4
EXPECT_EQ(human_readable_size(1127), "1.1 KiB");
EXPECT_EQ(human_readable_size(1146), "1.1 KiB");
}
TEST_CASE(border_KiB_MiB)
{
EXPECT_EQ(human_readable_size(1000 * KiB), "1000.0 KiB");
EXPECT_EQ(human_readable_size(1024 * KiB - 1), "1023.9 KiB");
// MiB
EXPECT_EQ(human_readable_size(1024 * KiB), "1.0 MiB");
EXPECT_EQ(human_readable_size(1024 * KiB + 1), "1.0 MiB");
}
TEST_CASE(fraction_MiB)
{
EXPECT_EQ(human_readable_size(1069547), "1.0 MiB");
EXPECT_EQ(human_readable_size(1101004), "1.0 MiB");
// 1024 * 1024 * 1.05 = 1101004.8
EXPECT_EQ(human_readable_size(1101005), "1.0 MiB");
EXPECT_EQ(human_readable_size(1101006), "1.0 MiB");
EXPECT_EQ(human_readable_size(1120000), "1.0 MiB");
EXPECT_EQ(human_readable_size(1153433), "1.0 MiB");
// 1024 * 1024 * 1.1 = 1153433.6
EXPECT_EQ(human_readable_size(1153434), "1.1 MiB");
}
TEST_CASE(border_MiB_GiB)
{
EXPECT_EQ(human_readable_size(1000 * MiB), "1000.0 MiB");
EXPECT_EQ(human_readable_size(1024 * MiB - 1), "1023.9 MiB");
EXPECT_EQ(human_readable_size(1024 * MiB), "1.0 GiB");
EXPECT_EQ(human_readable_size(1024 * MiB + 1), "1.0 GiB");
}
TEST_CASE(fraction_GiB)
{
EXPECT_EQ(human_readable_size(1095216660), "1.0 GiB");
EXPECT_EQ(human_readable_size(1127428915), "1.0 GiB");
// 1024 * 1024 * 1024 * 1.05 = 1127428915.2
EXPECT_EQ(human_readable_size(1127428916), "1.0 GiB");
EXPECT_EQ(human_readable_size(1127536289), "1.0 GiB");
EXPECT_EQ(human_readable_size(1154272461), "1.0 GiB");
EXPECT_EQ(human_readable_size(1181115968), "1.0 GiB");
EXPECT_EQ(human_readable_size(1181115969), "1.0 GiB");
EXPECT_EQ(human_readable_size(1181116000), "1.0 GiB");
EXPECT_EQ(human_readable_size(1181116006), "1.0 GiB");
// 1024 * 1024 * 1024 * 1.1 = 1181116006.4
EXPECT_EQ(human_readable_size(1181116007), "1.1 GiB");
EXPECT_EQ(human_readable_size(1202590842), "1.1 GiB");
}
TEST_CASE(extremes_4byte)
{
EXPECT_EQ(human_readable_size(0x7fffffff), "1.9 GiB");
EXPECT_EQ(human_readable_size(0x80000000), "2.0 GiB");
EXPECT_EQ(human_readable_size(0xffffffff), "3.9 GiB");
}
template<int>
void actual_extremes_8byte();
template<>
void actual_extremes_8byte<4>()
{
warn() << "(Skipping 8-byte-size_t test)";
}
template<>
void actual_extremes_8byte<8>()
{
warn() << "(Running true 8-byte-size_t test)";
// Your editor might show "implicit conversion" warnings here.
// This is because your editor thinks the world is 32-bit, but it isn't.
EXPECT_EQ(human_readable_size(0x100000000ULL), "4.0 GiB");
EXPECT_EQ(human_readable_size(0x100000001ULL), "4.0 GiB");
EXPECT_EQ(human_readable_size(0x800000000ULL), "32.0 GiB");
EXPECT_EQ(human_readable_size(0x10000000000ULL), "1024.0 GiB");
// Oh yeah! These are *correct*!
EXPECT_EQ(human_readable_size(0x7fffffffffffffffULL), "8589934591.9 GiB");
EXPECT_EQ(human_readable_size(0x8000000000000000ULL), "8589934592.0 GiB");
EXPECT_EQ(human_readable_size(0xffffffffffffffffULL), "17179869183.9 GiB");
}
TEST_CASE(extremes_8byte)
{
actual_extremes_8byte<sizeof(size_t)>();
}
TEST_MAIN(NumberFormat)