Clang: Do not replace class completion with constructor completion

Both completion kinds have the same name. Do not merge them
together when looking for constructor overloads.

Task-number: QTCREATORBUG-21010
Change-Id: I4c851033d63ad4e242b6179491f1fba00af466f6
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

src/plugins/clangcodemodel/clangassistproposalmodel.cpp

@@ -63,7 +63,8 @@ void ClangAssistProposalModel::sort(const QString &/*prefix*/)
                     || (first->order() == second->order() && first->text() < second->text())));
     };
 
-    std::sort(m_currentItems.begin(), m_currentItems.end(), currentItemsCompare);
+    // Keep the order for the items with the same priority and name.
+    std::stable_sort(m_currentItems.begin(), m_currentItems.end(), currentItemsCompare);
 }
 
 } // namespace Internal

src/plugins/clangcodemodel/clangcompletionassistprocessor.cpp

@@ -133,12 +133,14 @@ static QList<AssistProposalItemInterface *> toAssistProposalItems(
             auto samePreviousConstructor
                     = std::find_if(items.begin(),
                                    items.end(),
-                                   [&name](const AssistProposalItemInterface *item) {
-                return item->text() == name;
+                                   [&](const AssistProposalItemInterface *item) {
+                return item->text() == name
+                        && static_cast<const ClangAssistProposalItem *>(item)->firstCodeCompletion()
+                        .completionKind == codeCompletion.completionKind;
             });
             if (samePreviousConstructor == items.end()) {
                 addAssistProposalItem(items, codeCompletion, name);
-            } else {
+            } else if (codeCompletion.completionKind == CodeCompletion::ConstructorCompletionKind){
                 addFunctionOverloadAssistProposalItem(items, *samePreviousConstructor, interface,
                                                       codeCompletion, name);
             }

src/plugins/clangcodemodel/test/clangcodecompletion_test.cpp

@@ -361,6 +361,20 @@ bool hasItem(TextEditor::ProposalModelPtr model, const QByteArray &text)
     return indexOfItemWithText(model, text) != -1;
 }
 
+int itemsWithText(TextEditor::ProposalModelPtr model, const QByteArray &text)
+{
+    if (!model)
+        return 0;
+
+    int amount = 0;
+    for (int i = 0, size = model->size(); i < size; ++i) {
+        if (model->text(i) == QString::fromUtf8(text))
+            ++amount;
+    }
+
+    return amount;
+}
+
 bool hasItem(TextEditor::ProposalModelPtr model, const QByteArray &text, const QByteArray &detail)
 {
     const int index = indexOfItemWithText(model, text);
@@ -571,6 +585,13 @@ void ClangCodeCompletionTest::testCompleteConstructor()
     QVERIFY(hasItem(t.proposal, "Foo(int, double)"));
 }
 
+void ClangCodeCompletionTest::testCompleteClassAndConstructor()
+{
+    ProjectLessCompletionTest t("classAndConstructorCompletion.cpp");
+
+    QCOMPARE(itemsWithText(t.proposal, "Foo"), 2);
+}
+
 // Explicitly Inserting The Dot
 // ----------------------------
 // Inserting the dot for is important since it will send the editor
@@ -582,7 +603,7 @@ void ClangCodeCompletionTest::testCompleteWithDotToArrowCorrection()
     ProjectLessCompletionTest t("dotToArrowCorrection.cpp",
                                 QStringLiteral(".")); // See above "Explicitly Inserting The Dot"
 
-    QVERIFY(hasItem(t.proposal, "member"));
+    QVERIFY(hasItem(t.proposal, "member (requires to correct [4:8-4:9] to \"->\")"));
 }
 
 void ClangCodeCompletionTest::testDontCompleteWithDotToArrowCorrectionForFloats()

src/plugins/clangcodemodel/test/clangcodecompletion_test.h

@@ -46,6 +46,7 @@ private slots:
     void testCompleteMembers();
     void testCompleteFunctions();
     void testCompleteConstructor();
+    void testCompleteClassAndConstructor();
 
     void testCompleteWithDotToArrowCorrection();
     void testDontCompleteWithDotToArrowCorrectionForFloats();

src/plugins/clangcodemodel/test/data/clangtestdata.qrc

@@ -23,5 +23,6 @@
         <file>preprocessorKeywordsCompletion.cpp</file>
         <file>dotToArrowCorrection.cpp</file>
         <file>noDotToArrowCorrectionForFloats.cpp</file>
+        <file>classAndConstructorCompletion.cpp</file>
     </qresource>
 </RCC>

src/plugins/clangcodemodel/test/data/classAndConstructorCompletion.cpp

@@ -0,0 +1,8 @@
+struct Foo {
+    Foo(int) {}
+    Foo(int, double) {}
+};
+
+void f() {
+    Fo /* COMPLETE HERE */
+}