AK: Add tests for human_readable_size()

1 files changed, 163 insertions, 0 deletions

diff --git a/AK/Tests/TestNumberFormat.cpp b/AK/Tests/TestNumberFormat.cpp
new file mode 100644
index 0000000000..fb9619ead5
--- /dev/null
+++ b/AK/Tests/TestNumberFormat.cpp
@@ -0,0 +1,163 @@
+/*
+ * 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), "1024.0 MiB"); // TODO
+    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), "1.1 GiB"); // TODO
+    EXPECT_EQ(human_readable_size(1181116000), "1.1 GiB"); // TODO
+    EXPECT_EQ(human_readable_size(1181116006), "1.1 GiB"); // TODO
+    // 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), "2.0 GiB"); // TODO
+    EXPECT_EQ(human_readable_size(0x80000000), "2.0 GiB");
+    EXPECT_EQ(human_readable_size(0xffffffff), "4.0 GiB"); // TODO
+}
+
+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");
+
+    // Ehh, too bad.
+    EXPECT_EQ(human_readable_size(0x7fffffffffffffffULL), "-2147483648.-2147483648 GiB");
+    EXPECT_EQ(human_readable_size(0x8000000000000000ULL), "-2147483648.-2147483648 GiB");
+    EXPECT_EQ(human_readable_size(0xffffffffffffffffULL), "-2147483648.-2147483648 GiB");
+}
+
+TEST_CASE(extremes_8byte)
+{
+    actual_extremes_8byte<sizeof(size_t)>();
+}
+
+TEST_MAIN(NumberFormat)