From 9ded5ae81007fd16536a033c63a8c4a2b824e713 Mon Sep 17 00:00:00 2001
From: Erik Verbruggen <erik@verbruggen.consulting>
Date: Fri, 29 Sep 2023 16:41:03 +0200
Subject: [PATCH] Remove custom data size formatting

It is replaced by `QLocale::formattedDataSize`. The precision is now:
0 fraction digits for bytes and KB, 1 for MB, and 2 for GB and above.

Fixes: #11024
---
 src/common/utility.cpp | 46 ++++++++++--------------------------------
 test/testutility.cpp   | 32 ++++++++++++++---------------
 2 files changed, 27 insertions(+), 51 deletions(-)

diff --git a/src/common/utility.cpp b/src/common/utility.cpp
index 392aafc1258..4ed66dee956 100644
--- a/src/common/utility.cpp
+++ b/src/common/utility.cpp
@@ -84,44 +84,20 @@ QString Utility::formatFingerprint(const QByteArray &fmhash, bool colonSeparated
 
 QString Utility::octetsToString(qint64 octets)
 {
-#define THE_FACTOR 1024
-    static const qint64 kb = THE_FACTOR;
-    static const qint64 mb = THE_FACTOR * kb;
-    static const qint64 gb = THE_FACTOR * mb;
-
-    QString s;
-    qreal value = octets;
-
-    // Whether we care about decimals: only for GB/MB and only
-    // if it's less than 10 units.
-    bool round = true;
-
-    // do not display terra byte with the current units, as when
-    // the MB, GB and KB units were made, there was no TB,
-    // see the JEDEC standard
-    // https://en.wikipedia.org/wiki/JEDEC_memory_standards
-    if (octets >= gb) {
-        s = QCoreApplication::translate("Utility", "%L1 GB");
-        value /= gb;
-        round = false;
-    } else if (octets >= mb) {
-        s = QCoreApplication::translate("Utility", "%L1 MB");
-        value /= mb;
-        round = false;
-    } else if (octets >= kb) {
-        s = QCoreApplication::translate("Utility", "%L1 KB");
-        value /= kb;
-    } else {
-        s = QCoreApplication::translate("Utility", "%L1 B");
-    }
+    OC_ASSERT(octets >= 0)
 
-    if (value > 9.95)
-        round = true;
+    using namespace FileSystem::SizeLiterals;
 
-    if (round)
-        return s.arg(qRound(value));
+    // We do what macOS 10.8 and above do: 0 fraction digits for bytes and KB; 1 fraction digits for MB; 2 for GB and above.
+    // See also https://developer.apple.com/documentation/foundation/nsbytecountformatter/1417887-adaptive
+    int precision = 0;
+    if (quint64(octets) >= 1_gb) {
+        precision = 2;
+    } else if (quint64(octets) >= 1_mb) {
+        precision = 1;
+    }
 
-    return s.arg(value, 0, 'g', 2);
+    return QLocale().formattedDataSize(octets, precision, QLocale::DataSizeTraditionalFormat);
 }
 
 // Qtified version of get_platforms() in csync_owncloud.c
diff --git a/test/testutility.cpp b/test/testutility.cpp
index 09a8c431305..06e6f042f51 100644
--- a/test/testutility.cpp
+++ b/test/testutility.cpp
@@ -31,25 +31,25 @@ private slots:
     void testOctetsToString()
     {
         QLocale::setDefault(QLocale(QStringLiteral("en")));
-        QCOMPARE(octetsToString(999), QString::fromLatin1("999 B"));
-        QCOMPARE(octetsToString(1024), QString::fromLatin1("1 KB"));
-        QCOMPARE(octetsToString(1364), QString::fromLatin1("1 KB"));
+        QCOMPARE(octetsToString(999), QString::fromLatin1("999 bytes"));
+        QCOMPARE(octetsToString(1024), QString::fromLatin1("1 kB"));
+        QCOMPARE(octetsToString(1364), QString::fromLatin1("1 kB"));
 
-        QCOMPARE(octetsToString(9110), QString::fromLatin1("9 KB"));
-        QCOMPARE(octetsToString(9910), QString::fromLatin1("10 KB"));
-        QCOMPARE(octetsToString(10240), QString::fromLatin1("10 KB"));
+        QCOMPARE(octetsToString(9110), QString::fromLatin1("9 kB"));
+        QCOMPARE(octetsToString(9910), QString::fromLatin1("10 kB"));
+        QCOMPARE(octetsToString(10240), QString::fromLatin1("10 kB"));
 
-        QCOMPARE(octetsToString(123456), QString::fromLatin1("121 KB"));
+        QCOMPARE(octetsToString(123456), QString::fromLatin1("121 kB"));
         QCOMPARE(octetsToString(1234567), QString::fromLatin1("1.2 MB"));
-        QCOMPARE(octetsToString(12345678), QString::fromLatin1("12 MB"));
-        QCOMPARE(octetsToString(123456789), QString::fromLatin1("118 MB"));
-        QCOMPARE(octetsToString(1000LL * 1000 * 1000 * 5), QString::fromLatin1("4.7 GB"));
-
-        QCOMPARE(octetsToString(1), QString::fromLatin1("1 B"));
-        QCOMPARE(octetsToString(2), QString::fromLatin1("2 B"));
-        QCOMPARE(octetsToString(1024), QString::fromLatin1("1 KB"));
-        QCOMPARE(octetsToString(1024 * 1024), QString::fromLatin1("1 MB"));
-        QCOMPARE(octetsToString(1024LL * 1024 * 1024), QString::fromLatin1("1 GB"));
+        QCOMPARE(octetsToString(12345678), QString::fromLatin1("11.8 MB"));
+        QCOMPARE(octetsToString(123456789), QString::fromLatin1("117.7 MB"));
+        QCOMPARE(octetsToString(1000LL * 1000 * 1000 * 5), QString::fromLatin1("4.66 GB"));
+
+        QCOMPARE(octetsToString(1), QString::fromLatin1("1 bytes"));
+        QCOMPARE(octetsToString(2), QString::fromLatin1("2 bytes"));
+        QCOMPARE(octetsToString(1024), QString::fromLatin1("1 kB"));
+        QCOMPARE(octetsToString(1024 * 1024), QString::fromLatin1("1.0 MB"));
+        QCOMPARE(octetsToString(1024LL * 1024 * 1024), QString::fromLatin1("1.00 GB"));
     }
 
     void testLaunchOnStartup()