2 files changed, 56 insertions, 8 deletions
diff --git a/tests/auto/corelib/tools/qhash/tst_qhash.cpp b/tests/auto/corelib/tools/qhash/tst_qhash.cpp
index ed21dc71b5..50b1248d91 100644
--- a/tests/auto/corelib/tools/qhash/tst_qhash.cpp
+++ b/tests/auto/corelib/tools/qhash/tst_qhash.cpp
@@ -76,6 +76,8 @@ private slots:
 
     void reserveShared();
     void reserveLessThanCurrentAmount();
+    void reserveKeepCapacity_data();
+    void reserveKeepCapacity();
 
     void QTBUG98265();
 
@@ -2693,6 +2695,40 @@ void tst_QHash::reserveLessThanCurrentAmount()
     }
 }
 
+void tst_QHash::reserveKeepCapacity_data()
+{
+    QTest::addColumn<qsizetype>("requested");
+    auto addRow = [](qsizetype requested) {
+        QTest::addRow("%td", ptrdiff_t(requested)) << requested;
+    };
+
+    QHash<int, int> testHash = {{1, 1}};
+    qsizetype minCapacity = testHash.capacity();
+    addRow(minCapacity - 1);
+    addRow(minCapacity + 0);
+    addRow(minCapacity + 1);
+    addRow(2 * minCapacity - 1);
+    addRow(2 * minCapacity + 0);
+    addRow(2 * minCapacity + 1);
+}
+
+void tst_QHash::reserveKeepCapacity()
+{
+    QFETCH(qsizetype, requested);
+
+    QHash<qsizetype, qsizetype> hash;
+    hash.reserve(requested);
+    qsizetype initialCapacity = hash.capacity();
+    QCOMPARE_GE(initialCapacity, requested);
+
+    // insert this many elements into the hash
+    for (qsizetype i = 0; i < requested; ++i)
+        hash.insert(i, i);
+
+    // it mustn't have increased capacity after inserting the elements
+    QCOMPARE(hash.capacity(), initialCapacity);
+}
+
 void tst_QHash::QTBUG98265()
 {
     QMultiHash<QUuid, QByteArray> a;
diff --git a/tests/auto/corelib/tools/qset/tst_qset.cpp b/tests/auto/corelib/tools/qset/tst_qset.cpp
index 734d1d491b..391e00485c 100644
--- a/tests/auto/corelib/tools/qset/tst_qset.cpp
+++ b/tests/auto/corelib/tools/qset/tst_qset.cpp
@@ -232,27 +232,39 @@ void tst_QSet::squeeze()
     set.squeeze();
     QVERIFY(set.capacity() < 100);
 
-    for (int i = 0; i < 512; ++i)
+    for (int i = 0; i < 500; ++i)
         set.insert(i);
-    QVERIFY(set.capacity() == 512);
+    QCOMPARE(set.size(), 500);
+
+    // squeezed capacity for 500 elements
+    qsizetype capacity = set.capacity();    // current implementation: 512
+    QCOMPARE_GE(capacity, set.size());
 
     set.reserve(50000);
-    QVERIFY(set.capacity() >= 50000);
+    QVERIFY(set.capacity() >= 50000);       // current implementation: 65536
 
     set.squeeze();
-    QVERIFY(set.capacity() == 512);
+    QCOMPARE(set.capacity(), capacity);
 
+    // removing elements does not shed capacity
     set.remove(499);
-    QVERIFY(set.capacity() == 512);
+    QCOMPARE(set.capacity(), capacity);
 
     set.insert(499);
-    QVERIFY(set.capacity() == 512);
+    QCOMPARE(set.capacity(), capacity);
 
-    set.insert(1000);
-    QVERIFY(set.capacity() == 1024);
+    // grow it beyond the current capacity
+    for (int i = set.size(); i <= capacity; ++i)
+        set.insert(i);
+    QCOMPARE(set.size(), capacity + 1);
+    QCOMPARE_GT(set.capacity(), capacity + 1);// current implementation: 2 * capacity (1024)
 
     for (int i = 0; i < 500; ++i)
         set.remove(i);
+
+    // removing elements does not shed capacity
+    QCOMPARE_GT(set.capacity(), capacity + 1);
+
     set.squeeze();
     QVERIFY(set.capacity() < 100);
 }