natural sort: exclude extension when comparing filenames

Currently natural sort compares the entire filenames
(basename.extension) when sorting. This causes eg.
"a 2.txt" to appear before "a.txt" when sorted by ascending.
This is unintuitive since people prioritize basenames more
than file extensions.

Instead, change natural sort to compare by basename only and
fallback to comparing extensions if basenames were equal.
This change causes "a.txt" to appear before "a 2.txt" and
matches how other platforms such as GNOME and Windows behave.

BUG: 416025
BUG: 470538
BUG: 421869
BUG: 312027

1 files changed, 78 insertions, 0 deletions

diff --git a/src/tests/kfileitemmodeltest.cpp b/src/tests/kfileitemmodeltest.cpp
index 7af5690ff..4b1814391 100644
--- a/src/tests/kfileitemmodeltest.cpp
+++ b/src/tests/kfileitemmodeltest.cpp
@@ -69,6 +69,7 @@ private Q_SLOTS:
     void testMakeExpandedItemHidden();
     void testRemoveFilteredExpandedItems();
     void testSorting();
+    void testNaturalSorting();
     void testIndexForKeyboardSearch();
     void testNameFilter();
     void testEmptyPath();
@@ -1275,6 +1276,83 @@ void KFileItemModelTest::testSorting()
     QCOMPARE(itemsMovedSpy.takeFirst().at(1).value<QList<int>>(), QList<int>() << 2 << 4 << 5 << 3 << 0 << 1 << 6 << 7 << 9 << 8);
 }
 
+void KFileItemModelTest::testNaturalSorting()
+{
+    QSignalSpy itemsInsertedSpy(m_model, &KFileItemModel::itemsInserted);
+    QSignalSpy itemsMovedSpy(m_model, &KFileItemModel::itemsMoved);
+    QVERIFY(itemsMovedSpy.isValid());
+
+    m_model->setSortRole("text");
+    m_model->setShowHiddenFiles(true);
+
+    m_testDir->createFiles({".a", "a.txt", "b.txt", "a 1.txt", "a 2.txt", "a 10.txt", "a.tar", "b.tar"});
+
+    m_model->loadDirectory(m_testDir->url());
+    QVERIFY(itemsInsertedSpy.wait());
+
+    // Sort by Name, ascending, natural sorting enabled
+    QCOMPARE(m_model->sortRole(), QByteArray("text"));
+    QCOMPARE(m_model->sortOrder(), Qt::AscendingOrder);
+    QCOMPARE(itemsInModel(),
+             QStringList() << ".a"
+                           << "a.tar"
+                           << "a.txt"
+                           << "a 1.txt"
+                           << "a 2.txt"
+                           << "a 10.txt"
+                           << "b.tar"
+                           << "b.txt");
+
+    // Sort by Extension
+    m_model->setSortRole("extension");
+    QCOMPARE(m_model->sortRole(), QByteArray("extension"));
+    QCOMPARE(itemsInModel(),
+             QStringList() << ".a"
+                           << "a.tar"
+                           << "b.tar"
+                           << "a.txt"
+                           << "a 1.txt"
+                           << "a 2.txt"
+                           << "a 10.txt"
+                           << "b.txt");
+    QCOMPARE(itemsMovedSpy.count(), 1);
+    QCOMPARE(itemsMovedSpy.first().at(0).value<KItemRange>(), KItemRange(2, 5));
+    QCOMPARE(itemsMovedSpy.takeFirst().at(1).value<QList<int>>(), QList<int>() << 3 << 4 << 5 << 6 << 2);
+
+    // Disable natural sorting, refresh directory for the change to take effect
+    m_model->m_naturalSorting = false;
+    m_model->refreshDirectory(m_model->directory());
+    QVERIFY(itemsInsertedSpy.wait());
+
+    // Sort by Extension, ascending, natural sorting disabled
+    QCOMPARE(m_model->sortRole(), QByteArray("extension"));
+    QCOMPARE(itemsInModel(),
+             QStringList() << ".a"
+                           << "a.tar"
+                           << "b.tar"
+                           << "a 1.txt"
+                           << "a 10.txt"
+                           << "a 2.txt"
+                           << "a.txt"
+                           << "b.txt");
+
+    // Sort by Name
+    m_model->setSortRole("text");
+    QCOMPARE(m_model->sortRole(), QByteArray("text"));
+    QCOMPARE(itemsInModel(),
+             QStringList() << ".a"
+                           << "a 1.txt"
+                           << "a 10.txt"
+                           << "a 2.txt"
+                           << "a.tar"
+                           << "a.txt"
+                           << "b.tar"
+                           << "b.txt");
+    QCOMPARE(itemsMovedSpy.count(), 1);
+    QCOMPARE(itemsMovedSpy.first().at(0).value<KItemRange>(), KItemRange(1, 6));
+    QCOMPARE(itemsMovedSpy.takeFirst().at(1).value<QList<int>>(), QList<int>() << 4 << 6 << 1 << 2 << 3 << 5);
+}
+
 void KFileItemModelTest::testIndexForKeyboardSearch()
 {
     QSignalSpy itemsInsertedSpy(m_model, &KFileItemModel::itemsInserted);