QtConcurrent: filter/map reduction without default ctor

Previously a default constructor was required for the result type
of mappedReduced() and filteredReduced(), even if a default value
was provided.

This patch fixes the problem.

The issue was in the ResultReporter type, that was calling
QList::resize() to adjust the size of expected reported results.
A default-value parameter was added to the class, so that
a corresponding overload of QList::resize could be invoked.

Task-number: QTBUG-88452
Change-Id: I51113753e314d76aa74d201b5a7e327a6ca75f47
Reviewed-by: Sona Kurazyan <sona.kurazyan@qt.io>

2 files changed, 78 insertions, 0 deletions

diff --git a/tests/auto/concurrent/qtconcurrentfiltermapgenerated/tst_qtconcurrent_selected_tests.cpp b/tests/auto/concurrent/qtconcurrentfiltermapgenerated/tst_qtconcurrent_selected_tests.cpp
index ebe6dba70e..6b72648720 100644
--- a/tests/auto/concurrent/qtconcurrentfiltermapgenerated/tst_qtconcurrent_selected_tests.cpp
+++ b/tests/auto/concurrent/qtconcurrentfiltermapgenerated/tst_qtconcurrent_selected_tests.cpp
@@ -294,3 +294,79 @@ void tst_QtConcurrentFilterMapGenerated::moveOnlyReductionItem()
 
     QCOMPARE(result, expected_result);*/
 }
+
+void tst_QtConcurrentFilterMapGenerated::noDefaultConstructorItemMapped()
+{
+    /* test for
+    template<typename typename ResultType, typename Sequence, typename MapFunctor, typename
+    ReduceFunctor, typename reductionitemtype> ResultType blockingMappedReduced(QThreadPool* pool,
+    const Sequence & sequence, MapFunctor function, ReduceFunctor reduceFunction, reductionitemtype
+    && initialValue, ReduceOptions);
+
+    with
+      inputsequence=standard
+      inputsequencepassing=lvalue
+      inputitemtype=standard
+      maptype=same
+      mappeditemtype=standard
+      reductiontype=different
+      reductionitemtype=noconstruct
+      mapfunction=functor
+      mapfunctionpassing=lvalue
+      reductionfunction=function
+      reductionfunctionpassing=lvalue
+      reductioninitialvaluepassing=lvalue
+      reductionoptions=unspecified
+    */
+
+    QThreadPool pool;
+    pool.setMaxThreadCount(1);
+    auto input_sequence = []() {
+        std::vector<SequenceItem<tag_input>> result;
+        result.push_back(SequenceItem<tag_input>(1, true));
+        result.push_back(SequenceItem<tag_input>(2, true));
+        result.push_back(SequenceItem<tag_input>(3, true));
+        result.push_back(SequenceItem<tag_input>(4, true));
+        result.push_back(SequenceItem<tag_input>(5, true));
+        result.push_back(SequenceItem<tag_input>(6, true));
+        return result;
+    }();
+
+    auto map = MyMap<SequenceItem<tag_input>, SequenceItem<tag_input>> {};
+    auto reductor = myReduce<SequenceItem<tag_input>, NoConstructSequenceItem<tag_reduction>>;
+    auto initialvalue = NoConstructSequenceItem<tag_reduction>(0, true);
+
+    auto result =
+            QtConcurrent::blockingMappedReduced(&pool, input_sequence, map, reductor, initialvalue);
+
+    auto expected_result = NoConstructSequenceItem<tag_reduction>(42, true);
+
+    QCOMPARE(result, expected_result);
+}
+
+void tst_QtConcurrentFilterMapGenerated::noDefaultConstructorItemFiltered()
+{
+    QThreadPool pool;
+    pool.setMaxThreadCount(1);
+    auto input_sequence = []() {
+        std::vector<SequenceItem<tag_input>> result;
+        result.push_back(SequenceItem<tag_input>(1, true));
+        result.push_back(SequenceItem<tag_input>(2, true));
+        result.push_back(SequenceItem<tag_input>(3, true));
+        result.push_back(SequenceItem<tag_input>(4, true));
+        result.push_back(SequenceItem<tag_input>(5, true));
+        result.push_back(SequenceItem<tag_input>(6, true));
+        return result;
+    }();
+
+    auto filter = MyFilter<SequenceItem<tag_input>> {};
+    auto reductor = myReduce<SequenceItem<tag_input>, NoConstructSequenceItem<tag_reduction>>;
+    auto initialvalue = NoConstructSequenceItem<tag_reduction>(0, true);
+
+    auto result = QtConcurrent::blockingFilteredReduced(&pool, input_sequence, filter, reductor,
+                                                        initialvalue);
+
+    auto expected_result = NoConstructSequenceItem<tag_reduction>(9, true);
+
+    QCOMPARE(result, expected_result);
+}
diff --git a/tests/auto/concurrent/qtconcurrentfiltermapgenerated/tst_qtconcurrentfiltermapgenerated.h b/tests/auto/concurrent/qtconcurrentfiltermapgenerated/tst_qtconcurrentfiltermapgenerated.h
index 9a32f53499..e6229236a3 100644
--- a/tests/auto/concurrent/qtconcurrentfiltermapgenerated/tst_qtconcurrentfiltermapgenerated.h
+++ b/tests/auto/concurrent/qtconcurrentfiltermapgenerated/tst_qtconcurrentfiltermapgenerated.h
@@ -44,6 +44,8 @@ private slots:
     void moveOnlyReduceObject();
     void functorAsReduction();
     void moveOnlyReductionItem();
+    void noDefaultConstructorItemMapped();
+    void noDefaultConstructorItemFiltered();
     // START_GENERATED_SLOTS (see generate_tests.py)
     void test1();
     // END_GENERATED_SLOTS (see generate_tests.py)