Remove the special code for emplaceFront/Back again

emplace() itself now handles those cases fast enough, so there
should not be a need to add special code paths for those methods.

Change-Id: I3277eb77dd54194e46f96f24de44d7785a6f860a
Reviewed-by: Andrei Golubev <andrei.golubev@qt.io>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/tools/qarraydataops.h

@@ -932,41 +932,6 @@ public:
             ++this->size;
         }
     }
-
-public:
-
-    template <typename ...Args>
-    void emplaceBack(Args&&... args)
-    {
-        if (this->needsDetach() || !this->freeSpaceAtEnd()) {
-            // protect against args being an element of the container
-            T tmp(std::forward<Args>(args)...);
-            this->reallocateAndGrow(QArrayData::GrowsAtEnd, 1);
-            Q_ASSERT(!this->isShared());
-            Q_ASSERT(this->freeSpaceAtEnd() >= 1);
-            new (this->end()) T(std::move(tmp));
-        } else {
-            new (this->end()) T(std::forward<Args>(args)...);
-        }
-        ++this->size;
-    }
-
-    template <typename ...Args>
-    void emplaceFront(Args&&... args)
-    {
-        if (this->needsDetach() || !this->freeSpaceAtBegin()) {
-            // protect against args being an element of the container
-            T tmp(std::forward<Args>(args)...);
-            this->reallocateAndGrow(QArrayData::GrowsAtBeginning, 1);
-            Q_ASSERT(!this->isShared());
-            Q_ASSERT(this->freeSpaceAtBegin() >= 1);
-            new (this->ptr - 1) T(std::move(tmp));
-        } else {
-            new (this->ptr - 1) T(std::forward<Args>(args)...);
-        }
-        --this->ptr;
-        ++this->size;
-    }
 };
 
 } // namespace QtPrivate

src/corelib/tools/qlist.h

@@ -715,7 +715,7 @@ template<typename T>
 template<typename... Args>
 inline typename QList<T>::reference QList<T>::emplaceFront(Args &&... args)
 {
-    d->emplaceFront(std::forward<Args>(args)...);
+    d->emplace(0, std::forward<Args>(args)...);
     return *d.begin();
 }
 
@@ -744,7 +744,7 @@ template<typename T>
 template<typename... Args>
 inline typename QList<T>::reference QList<T>::emplaceBack(Args &&... args)
 {
-    d->emplaceBack(std::forward<Args>(args)...);
+    d->emplace(d->size, std::forward<Args>(args)...);
     return *(d.end() - 1);
 }
 

tests/auto/corelib/tools/qarraydata/tst_qarraydata.cpp

@@ -2205,7 +2205,7 @@ void tst_QArrayData::selfEmplaceBackwards()
     const auto testSelfEmplace = [&](auto dummy, int spaceAtEnd, auto initValues) {
         auto adp = createDataPointer(100, spaceAtEnd, dummy);
         for (auto v : initValues) {
-            adp->emplaceBack(v);
+            adp->emplace(adp.size, v);
         }
         QVERIFY(!adp.freeSpaceAtEnd());
         QVERIFY(adp.freeSpaceAtBegin());
@@ -2244,11 +2244,12 @@ void tst_QArrayData::selfEmplaceForward()
     };
 
     const auto testSelfEmplace = [&](auto dummy, int spaceAtBegin, auto initValues) {
-        auto adp = createDataPointer(100, spaceAtBegin, dummy);
+        // need a -1 below as the first emplace will go towards the end (as the array is still empty)
+        auto adp = createDataPointer(100, spaceAtBegin - 1, dummy);
         auto reversedInitValues = initValues;
         std::reverse(reversedInitValues.begin(), reversedInitValues.end());
         for (auto v : reversedInitValues) {
-            adp->emplaceFront(v);
+            adp->emplace(0, v);
         }
         QVERIFY(!adp.freeSpaceAtBegin());
         QVERIFY(adp.freeSpaceAtEnd());