Fix occurrences of the contains/insert anti-pattern

Introduce and make use of Utils::insert() for QSet with a return value
that indicates whether insertion actually happened.

Change-Id: I655e4bc3553b74fea5ae8956205e4d8070118d63
Reviewed-by: hjk <hjk@qt.io>
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

src/libs/cplusplus/CppDocument.cpp

@@ -774,10 +774,8 @@ QSet<FilePath> Snapshot::allIncludesForDocument(const FilePath &filePath) const
         if (Document::Ptr doc = document(file)) {
             const FilePaths includedFiles = doc->includedFiles(Document::Duplicates::Keep);
             for (const FilePath &inc : includedFiles) {
-                if (!result.contains(inc)) {
+                if (Utils::insert(result, inc))
-                    result.insert(inc);
                     files.push(inc);
-                }
             }
         }
     }

src/libs/cplusplus/FastPreprocessor.cpp

@@ -6,6 +6,8 @@
 #include <cplusplus/Literals.h>
 #include <cplusplus/TranslationUnit.h>
 
+#include <utils/algorithm.h>
+
 #include <QDir>
 
 using namespace Utils;
@@ -65,9 +67,7 @@ void FastPreprocessor::sourceNeeded(int line, const FilePath &filePath, IncludeT
 
 void FastPreprocessor::mergeEnvironment(const FilePath &filePath)
 {
-    if (! _merged.contains(filePath)) {
+    if (Utils::insert(_merged, filePath)) {
-        _merged.insert(filePath);
-
         if (Document::Ptr doc = _snapshot.document(filePath)) {
             const QList<Document::Include> includes = doc->resolvedIncludes();
             for (const Document::Include &i : includes)

src/libs/cplusplus/LookupContext.cpp

@@ -78,8 +78,7 @@ static bool isNestedInstantiationEnclosingTemplate(
 {
     QSet<ClassOrNamespace *> processed;
     while (enclosingTemplateClassInstantiation
-           && !processed.contains(enclosingTemplateClassInstantiation)) {
+           && Utils::insert(processed, enclosingTemplateClassInstantiation)) {
-        processed.insert(enclosingTemplateClassInstantiation);
         if (enclosingTemplateClassInstantiation == nestedClassOrNamespaceInstantiation)
             return false;
         enclosingTemplateClassInstantiation = enclosingTemplateClassInstantiation->parent();
@@ -389,11 +388,10 @@ ClassOrNamespace *LookupContext::lookupType(const Name *name, Scope *scope,
                         }
                         if (const NamedType *namedTy = d->type()->asNamedType()) {
                             // Stop on recursive typedef declarations
-                            if (typedefsBeingResolved.contains(d))
+                            if (!Utils::insert(typedefsBeingResolved, d))
                                 return nullptr;
                             return lookupType(namedTy->name(), scope, nullptr,
-                                              QSet<const Declaration *>(typedefsBeingResolved)
+                                              typedefsBeingResolved);
-                                                << d);
                         }
                     }
                 }
@@ -504,9 +502,8 @@ QList<LookupItem> LookupContext::lookup(const Name *name, Scope *scope) const
                     // try find this name in parent class
                     QSet<ClassOrNamespace *> processed;
                     while (candidates.isEmpty() && (binding = binding->parent())) {
-                        if (processed.contains(binding))
+                        if (!Utils::insert(processed, binding))
                             break;
-                        processed.insert(binding);
                         candidates = binding->find(name);
                     }
 
@@ -683,9 +680,8 @@ QList<LookupItem> ClassOrNamespace::lookup_helper(const Name *name, bool searchI
                 for (ClassOrNamespace *parentBinding = binding->parent();
                         parentBinding && !match;
                         parentBinding = parentBinding->parent()) {
-                    if (processed.contains(parentBinding))
+                    if (!Utils::insert(processed, parentBinding))
                         break;
-                    processed.insert(parentBinding);
                     match = parentBinding->lookupInScope(fullName);
                 }
 
@@ -704,9 +700,8 @@ QList<LookupItem> ClassOrNamespace::lookup_helper(const Name *name, bool searchI
         QSet<ClassOrNamespace *> processedOwnParents;
         ClassOrNamespace *binding = this;
         do {
-            if (processedOwnParents.contains(binding))
+            if (!Utils::insert(processedOwnParents, binding))
                 break;
-            processedOwnParents.insert(binding);
             lookup_helper(name, binding, &result, &processed, /*templateId = */ nullptr);
             binding = binding->_parent;
         } while (searchInEnclosingScope && binding);
@@ -720,9 +715,7 @@ void ClassOrNamespace::lookup_helper(const Name *name, ClassOrNamespace *binding
                                           QSet<ClassOrNamespace *> *processed,
                                           const TemplateNameId *templateId)
 {
-    if (binding && ! processed->contains(binding)) {
+    if (binding && Utils::insert(*processed, binding)) {
-        processed->insert(binding);
-
         const Identifier *nameId = name->identifier();
 
         const QList<Symbol *> symbols = binding->symbols();
@@ -902,9 +895,8 @@ ClassOrNamespace *ClassOrNamespace::findBlock_helper(Block *block,
                                                      bool searchInEnclosingScope)
 {
     for (ClassOrNamespace *binding = this; binding; binding = binding->_parent) {
-        if (processed->contains(binding))
+        if (!Utils::insert(*processed, binding))
             break;
-        processed->insert(binding);
         binding->flush();
         auto end = binding->_blocks.end();
         auto citBlock = binding->_blocks.find(block);
@@ -977,9 +969,7 @@ ClassOrNamespace *ClassOrNamespace::lookupType_helper(const Name *name,
 
         return nullptr;
 
-    } else if (! processed->contains(this)) {
+    } else if (Utils::insert(*processed, this)) {
-        processed->insert(this);
-
         if (name->asNameId() || name->asTemplateNameId() || name->asAnonymousNameId()) {
             flush();
 
@@ -1260,9 +1250,8 @@ ClassOrNamespace *ClassOrNamespace::nestedType(const Name *name,
 
         QSet<ClassOrNamespace *> otherProcessed;
         while (!origin->_symbols.isEmpty() && origin->_symbols[0]->asBlock()) {
-            if (otherProcessed.contains(origin))
+            if (!Utils::insert(otherProcessed, origin))
                 break;
-            otherProcessed.insert(origin);
             origin = origin->parent();
         }
 
@@ -1489,9 +1478,8 @@ void ClassOrNamespace::NestedClassInstantiator::instantiate(ClassOrNamespace *en
 {
     if (_alreadyConsideredNestedClassInstantiations.size() >= 3)
         return;
-    if (_alreadyConsideredNestedClassInstantiations.contains(enclosingTemplateClass))
+    if (!Utils::insert(_alreadyConsideredNestedClassInstantiations, enclosingTemplateClass))
         return;
-    _alreadyConsideredNestedClassInstantiations.insert(enclosingTemplateClass);
     ClassOrNamespace::Table::const_iterator cit = enclosingTemplateClass->_classOrNamespaces.begin();
     for (; cit != enclosingTemplateClass->_classOrNamespaces.end(); ++cit) {
         const Name *nestedName = cit->first;
@@ -1720,9 +1708,7 @@ void CreateBindings::process(Document::Ptr doc)
         return;
 
     if (Namespace *globalNamespace = doc->globalNamespace()) {
-        if (! _processed.contains(globalNamespace)) {
+        if (Utils::insert(_processed, globalNamespace)) {
-            _processed.insert(globalNamespace);
-
             const QList<Document::Include> includes = doc->resolvedIncludes();
             for (const Document::Include &i : includes) {
                 if (Document::Ptr incl = _snapshot.document(i.resolvedFileName()))

src/libs/cplusplus/ResolveExpression.cpp

@@ -6,7 +6,6 @@
 #include "LookupContext.h"
 #include "Overview.h"
 #include "DeprecatedGenTemplateInstance.h"
-#include "CppRewriter.h"
 #include "TypeOfExpression.h"
 
 #include <cplusplus/Control.h>
@@ -20,6 +19,8 @@
 #include <cplusplus/NameVisitor.h>
 #include <cplusplus/Templates.h>
 
+#include <utils/algorithm.h>
+
 #include <QList>
 #include <QDebug>
 #include <QSet>
@@ -142,9 +143,8 @@ private:
         for (const LookupItem &it : namedTypeItems) {
             Symbol *declaration = it.declaration();
             if (declaration && declaration->isTypedef()) {
-                if (visited.contains(declaration))
+                if (!Utils::insert(visited, declaration))
                     break;
-                visited.insert(declaration);
 
                 // continue working with the typedefed type and scope
                 if (type->type()->asPointerType()) {

src/libs/cplusplus/SnapshotSymbolVisitor.cpp

@@ -5,6 +5,8 @@
 
 #include <cplusplus/Symbols.h>
 
+#include <utils/algorithm.h>
+
 using namespace CPlusPlus;
 
 SnapshotSymbolVisitor::SnapshotSymbolVisitor(const Snapshot &snapshot)
@@ -20,9 +22,7 @@ void SnapshotSymbolVisitor::accept(Document::Ptr doc)
 
 void SnapshotSymbolVisitor::accept(Document::Ptr doc, QSet<QString> *processed)
 {
-    if (doc && doc->globalNamespace() && ! processed->contains(doc->filePath().path())) {
+    if (doc && doc->globalNamespace() && Utils::insert(*processed, doc->filePath().path())) {
-        processed->insert(doc->filePath().path());
-
         const QList<Document::Include> includes = doc->resolvedIncludes();
         for (const Document::Include &i : includes) {
             if (Document::Ptr incl = _snapshot.document(i.resolvedFileName()))

src/libs/cplusplus/TypeOfExpression.cpp

@@ -11,6 +11,8 @@
 #include <cplusplus/Symbol.h>
 #include <cplusplus/TranslationUnit.h>
 
+#include <utils/algorithm.h>
+
 #include <QSet>
 
 using namespace Utils;
@@ -134,9 +136,7 @@ ExpressionAST *TypeOfExpression::expressionAST() const
 void TypeOfExpression::processEnvironment(Document::Ptr doc, Environment *env,
                                           QSet<QString> *processed) const
 {
-    if (doc && ! processed->contains(doc->filePath().path())) {
+    if (doc && Utils::insert(*processed, doc->filePath().path())) {
-        processed->insert(doc->filePath().path());
-
         const QList<Document::Include> includes = doc->resolvedIncludes();
         for (const Document::Include &incl : includes)
             processEnvironment(m_snapshot.document(incl.resolvedFileName()), env, processed);

src/libs/extensionsystem/pluginmanager.cpp

@@ -373,10 +373,8 @@ const QSet<PluginSpec *> PluginManager::pluginsRequiredByPlugin(PluginSpec *spec
             if (depIt.key().type != PluginDependency::Required)
                 continue;
             PluginSpec *depSpec = depIt.value();
-            if (!recursiveDependencies.contains(depSpec)) {
+            if (Utils::insert(recursiveDependencies, depSpec))
-                recursiveDependencies.insert(depSpec);
                 queue.push(depSpec);
-            }
         }
     }
     recursiveDependencies.remove(spec);

src/libs/qmljs/qmljslink.cpp

@@ -656,14 +656,12 @@ void LinkPrivate::loadQmldirComponents(ObjectValue *import,
     QSet<QString> importedTypes;
     const auto components = libraryInfo.components();
     for (const QmlDirParser::Component &component : components) {
-        if (importedTypes.contains(component.typeName))
-            continue;
-
         ComponentVersion componentVersion(component.majorVersion, component.minorVersion);
         if (version < componentVersion)
             continue;
 
-        importedTypes.insert(component.typeName);
+        if (!Utils::insert(importedTypes, component.typeName))
+            continue;
         if (Document::Ptr importedDoc = m_snapshot.document(
                 libraryPath.pathAppended(component.fileName))) {
             if (ObjectValue *v = importedDoc->bind()->rootObjectValue())

src/libs/qmljs/qmljsmodelmanagerinterface.cpp

@@ -734,10 +734,9 @@ static void findNewImplicitImports(const Document::Ptr &doc,
     // scan files that could be implicitly imported
     // it's important we also do this for JS files, otherwise the isEmpty check will fail
     if (snapshot.documentsInDirectory(doc->path()).isEmpty()) {
-        if (!scannedPaths->contains(doc->path())) {
+        if (Utils::insert(*scannedPaths, doc->path())) {
             *importedFiles += filesInDirectoryForLanguages(doc->path(),
                                                            doc->language().companionLanguages());
-            scannedPaths->insert(doc->path());
         }
     }
 }
@@ -757,11 +756,10 @@ static void findNewFileImports(const Document::Ptr &doc,
                 *importedFiles += importPath;
         } else if (import.type() == ImportType::Directory) {
             if (snapshot.documentsInDirectory(importPath).isEmpty()) {
-                if (!scannedPaths->contains(importPath)) {
+                if (Utils::insert(*scannedPaths, importPath)) {
                     *importedFiles
                         += filesInDirectoryForLanguages(importPath,
                                                         doc->language().companionLanguages());
-                    scannedPaths->insert(importPath);
                 }
             }
         } else if (import.type() == ImportType::QrcFile) {
@@ -890,10 +888,9 @@ static bool findNewQmlLibraryInPath(const Utils::FilePath &path,
         if (!component.fileName.isEmpty()) {
             const FilePath componentFile = path.pathAppended(component.fileName);
             const FilePath path = componentFile.absolutePath().cleanPath();
-            if (!scannedPaths->contains(path)) {
+            if (Utils::insert(*scannedPaths, path)) {
                 *importedFiles += filesInDirectoryForLanguages(path, Dialect(Dialect::AnyLanguage)
                                                                .companionLanguages());
-                scannedPaths->insert(path);
             }
         }
     }
@@ -1110,10 +1107,9 @@ void ModelManagerInterface::importScanAsync(QPromise<void> &promise, const Worki
         QMutexLocker l(&modelManager->m_mutex);
         for (const auto &path : paths) {
             Utils::FilePath cPath = path.path().cleanPath();
-            if (!forceRescan && modelManager->m_scannedPaths.contains(cPath))
+            if (!forceRescan && !Utils::insert(modelManager->m_scannedPaths, cPath))
                 continue;
             pathsToScan.append({cPath, 0, path.language()});
-            modelManager->m_scannedPaths.insert(cPath);
         }
     }
     const int maxScanDepth = 5;

src/libs/utils/algorithm.h

@@ -1437,4 +1437,13 @@ void addToHash(QHash<Key, T> *result, const QHash<Key, T> &additionalContents)
     result->insert(additionalContents);
 }
 
+// Workaround for missing information from QSet::insert()
+// Return type could be a pair like for std::set, but we never use the iterator anyway.
+template<typename T, typename U> [[nodiscard]] bool insert(QSet<T> &s, const U &v)
+{
+    const int oldSize = s.size();
+    s.insert(v);
+    return s.size() > oldSize;
+}
+
 } // namespace Utils

src/libs/utils/namevaluesdialog.cpp

@@ -3,7 +3,7 @@
 
 #include "namevaluesdialog.h"
 
-#include "environment.h"
+#include "algorithm.h"
 #include "hostosinfo.h"
 #include "utilstr.h"
 
@@ -29,10 +29,8 @@ static EnvironmentItems cleanUp(const EnvironmentItems &items)
         const QString &itemName = item.name;
         QString emptyName = itemName;
         emptyName.remove(QLatin1Char(' '));
-        if (!emptyName.isEmpty() && !uniqueSet.contains(itemName)) {
+        if (!emptyName.isEmpty() && Utils::insert(uniqueSet, itemName))
             uniqueItems.prepend(item);
-            uniqueSet.insert(itemName);
-        }
     }
     return uniqueItems;
 }

src/plugins/autotest/testresultmodel.cpp

@@ -10,6 +10,7 @@
 #include "testtreemodel.h"
 
 #include <projectexplorer/projectexplorericons.h>
+#include <utils/algorithm.h>
 #include <utils/qtcassert.h>
 
 #include <QFontMetrics>
@@ -202,10 +203,7 @@ bool TestResultItem::updateDescendantTypes(ResultType t)
     if (t == ResultType::TestStart || t == ResultType::TestEnd) // these are special
         return false;
 
-    if (m_descendantsTypes.contains(t))
+    return Utils::insert(m_descendantsTypes, t);
-        return false;
-    m_descendantsTypes.insert(t);
-    return true;
 }
 
 bool TestResultItem::descendantTypesContainsAnyOf(const QSet<ResultType> &types) const
@@ -467,8 +465,7 @@ void TestResultFilterModel::enableAllResultTypes(bool enabled)
 
 void TestResultFilterModel::toggleTestResultType(ResultType type)
 {
-    if (m_enabled.contains(type)) {
+    if (m_enabled.remove(type)) {
-        m_enabled.remove(type);
         if (type == ResultType::MessageInternal)
             m_enabled.remove(ResultType::TestEnd);
         if (type == ResultType::MessageDebug)

src/plugins/bineditor/bineditorwidget.cpp

@@ -18,6 +18,7 @@
 #include <texteditor/texteditorconstants.h>
 #include <texteditor/texteditorsettings.h>
 
+#include <utils/algorithm.h>
 #include <utils/fadingindicator.h>
 #include <utils/fileutils.h>
 #include <utils/qtcassert.h>
@@ -222,9 +223,8 @@ bool BinEditorWidget::requestDataAt(qint64 pos) const
     it = m_data.find(block);
     if (it != m_data.end())
         return true;
-    if (m_requests.contains(block))
+    if (!Utils::insert(m_requests, block))
         return false;
-    m_requests.insert(block);
     d->fetchData((m_baseAddr / m_blockSize + block) * m_blockSize);
     return true;
 }

src/plugins/cmakeprojectmanager/cmakebuildsystem.cpp

@@ -1301,9 +1301,8 @@ void CMakeBuildSystem::runCTest()
                         std::function<QJsonObject(int)> findAncestor = [&](int index){
                             const QJsonObject node = nodes.at(index).toObject();
                             const int parent = node.value("parent").toInt(-1);
-                            if (seen.contains(parent) || parent < 0)
+                            if (parent < 0 || !Utils::insert(seen, parent))
                                 return node;
-                            seen << parent;
                             return findAncestor(parent);
                         };
                         const QJsonObject btRef = findAncestor(bt);

src/plugins/coreplugin/editormanager/documentmodel.cpp

@@ -470,10 +470,8 @@ void DocumentModelPrivate::removeAllSuspendedEntries(PinnedFileRemovalPolicy pin
     QSet<QString> displayNames;
     for (DocumentModel::Entry *entry : std::as_const(d->m_entries)) {
         const QString displayName = entry->plainDisplayName();
-        if (displayNames.contains(displayName))
+        if (Utils::insert(displayNames, displayName))
-            continue;
+            d->disambiguateDisplayNames(entry);
-        displayNames.insert(displayName);
-        d->disambiguateDisplayNames(entry);
     }
 }
 

src/plugins/coreplugin/editormanager/openeditorswindow.cpp

@@ -9,6 +9,7 @@
 #include "../coreplugintr.h"
 #include "../idocument.h"
 
+#include <utils/algorithm.h>
 #include <utils/fsengine/fileiconprovider.h>
 #include <utils/hostosinfo.h>
 #include <utils/qtcassert.h>
@@ -219,9 +220,8 @@ void OpenEditorsWindow::addItem(DocumentModel::Entry *entry,
                                 QSet<const DocumentModel::Entry *> &entriesDone,
                                 EditorView *view)
 {
-    if (entriesDone.contains(entry))
+    if (!Utils::insert(entriesDone, entry))
         return;
-    entriesDone.insert(entry);
     QString title = entry->displayName();
     QTC_ASSERT(!title.isEmpty(), return);
     auto item = new QTreeWidgetItem();

src/plugins/cppcheck/cppcheckdiagnosticsmodel.cpp

@@ -7,6 +7,7 @@
 
 #include <debugger/analyzer/diagnosticlocation.h>
 
+#include <utils/algorithm.h>
 #include <utils/fsengine/fileiconprovider.h>
 #include <utils/utilsicons.h>
 
@@ -99,12 +100,10 @@ void DiagnosticsModel::clear()
 
 void DiagnosticsModel::add(const Diagnostic &diagnostic)
 {
-    if (m_diagnostics.contains(diagnostic))
+    if (!Utils::insert(m_diagnostics, diagnostic))
         return;
 
-    const auto hasData = !m_diagnostics.isEmpty();
+    if (m_diagnostics.size() == 1)
-    m_diagnostics.insert(diagnostic);
-    if (!hasData)
         emit hasDataChanged(true);
 
     const QString filePath = diagnostic.fileName.toString();

src/plugins/cppeditor/cppchecksymbols.cpp

@@ -73,9 +73,7 @@ protected:
     {
         if (!doc)
             return;
-        if (!processed->contains(doc->globalNamespace())) {
+        if (Utils::insert(*processed, doc->globalNamespace())) {
-            processed->insert(doc->globalNamespace());
-
             const QList<Document::Include> includes = doc->resolvedIncludes();
             for (const Document::Include &i : includes)
                 process(_snapshot.document(i.resolvedFileName()), processed);
@@ -806,8 +804,7 @@ bool CheckSymbols::hasVirtualDestructor(ClassOrNamespace *binding) const
 
     while (!todo.isEmpty()) {
         ClassOrNamespace *b = todo.takeFirst();
-        if (b && !processed.contains(b)) {
+        if (b && Utils::insert(processed, b)) {
-            processed.insert(b);
             const QList<Symbol *> symbols = b->symbols();
             for (Symbol *s : symbols) {
                 if (Class *k = s->asClass()) {

src/plugins/cppeditor/cppcompletionassist.cpp

@@ -20,6 +20,7 @@
 #include <texteditor/texteditorsettings.h>
 #include <texteditor/completionsettings.h>
 
+#include <utils/algorithm.h>
 #include <utils/mimeutils.h>
 #include <utils/qtcassert.h>
 #include <utils/textutils.h>
@@ -1459,9 +1460,8 @@ bool InternalCppCompletionAssistProcessor::globalCompletion(Scope *currentScope)
 
     QSet<ClassOrNamespace *> processed;
     for (; currentBinding; currentBinding = currentBinding->parent()) {
-        if (processed.contains(currentBinding))
+        if (!Utils::insert(processed, currentBinding))
             break;
-        processed.insert(currentBinding);
 
         const QList<ClassOrNamespace*> usings = currentBinding->usings();
         for (ClassOrNamespace* u : usings)
@@ -1598,10 +1598,9 @@ void InternalCppCompletionAssistProcessor::completeNamespace(ClassOrNamespace *b
 
     while (!bindingsToVisit.isEmpty()) {
         ClassOrNamespace *binding = bindingsToVisit.takeFirst();
-        if (!binding || bindingsVisited.contains(binding))
+        if (!binding || !Utils::insert(bindingsVisited, binding))
             continue;
 
-        bindingsVisited.insert(binding);
         bindingsToVisit += binding->usings();
 
         QList<Scope *> scopesToVisit;
@@ -1619,11 +1618,9 @@ void InternalCppCompletionAssistProcessor::completeNamespace(ClassOrNamespace *b
 
         while (!scopesToVisit.isEmpty()) {
             Scope *scope = scopesToVisit.takeFirst();
-            if (!scope || scopesVisited.contains(scope))
+            if (!scope || !Utils::insert(scopesVisited, scope))
                 continue;
 
-            scopesVisited.insert(scope);
-
             for (Scope::iterator it = scope->memberBegin(); it != scope->memberEnd(); ++it) {
                 Symbol *member = *it;
                 addCompletionItem(member);
@@ -1640,10 +1637,9 @@ void InternalCppCompletionAssistProcessor::completeClass(ClassOrNamespace *b, bo
 
     while (!bindingsToVisit.isEmpty()) {
         ClassOrNamespace *binding = bindingsToVisit.takeFirst();
-        if (!binding || bindingsVisited.contains(binding))
+        if (!binding || !Utils::insert(bindingsVisited, binding))
             continue;
 
-        bindingsVisited.insert(binding);
         bindingsToVisit += binding->usings();
 
         QList<Scope *> scopesToVisit;
@@ -1663,11 +1659,9 @@ void InternalCppCompletionAssistProcessor::completeClass(ClassOrNamespace *b, bo
 
         while (!scopesToVisit.isEmpty()) {
             Scope *scope = scopesToVisit.takeFirst();
-            if (!scope || scopesVisited.contains(scope))
+            if (!scope || !Utils::insert(scopesVisited, scope))
                 continue;
 
-            scopesVisited.insert(scope);
-
             if (staticLookup)
                 addCompletionItem(scope, InjectedClassNameOrder); // add a completion item for the injected class name.
 
@@ -1737,9 +1731,7 @@ bool InternalCppCompletionAssistProcessor::completeQtMethod(const QList<LookupIt
         todo.append(b);
         while (!todo.isEmpty()) {
             ClassOrNamespace *binding = todo.takeLast();
-            if (!processed.contains(binding)) {
+            if (Utils::insert(processed, binding)) {
-                processed.insert(binding);
-
                 const QList<Symbol *> symbols = binding->symbols();
                 for (Symbol *s : symbols)
                     if (Class *clazz = s->asClass())
@@ -1862,11 +1854,9 @@ void InternalCppCompletionAssistProcessor::addMacros_helper(const Snapshot &snap
 {
     Document::Ptr doc = snapshot.document(filePath);
 
-    if (!doc || processed->contains(doc->filePath()))
+    if (!doc || !Utils::insert(*processed, doc->filePath()))
         return;
 
-    processed->insert(doc->filePath());
-
     const QList<Document::Include> includes = doc->resolvedIncludes();
     for (const Document::Include &i : includes)
         addMacros_helper(snapshot, i.resolvedFileName(), processed, definedMacros);

src/plugins/cppeditor/cppfollowsymbolundercursor.cpp

@@ -17,6 +17,7 @@
 #include <cplusplus/SimpleLexer.h>
 #include <cplusplus/TypeOfExpression.h>
 #include <texteditor/textdocumentlayout.h>
+#include <utils/algorithm.h>
 #include <utils/textutils.h>
 #include <utils/qtcassert.h>
 
@@ -181,9 +182,7 @@ Class *VirtualFunctionHelper::staticClassOfFunctionCallExpression_internal() con
 Link findMacroLink_helper(const QByteArray &name, Document::Ptr doc, const Snapshot &snapshot,
                           QSet<QString> *processed)
 {
-    if (doc && !name.startsWith('<') && !processed->contains(doc->filePath().path())) {
+    if (doc && !name.startsWith('<') && Utils::insert(*processed, doc->filePath().path())) {
-        processed->insert(doc->filePath().path());
-
         for (const Macro &macro : doc->definedMacros()) {
             if (macro.name() == name) {
                 Link link;

src/plugins/cppeditor/cppmodelmanager.cpp

@@ -60,6 +60,7 @@
 
 #include <texteditor/textdocument.h>
 
+#include <utils/algorithm.h>
 #include <utils/environment.h>
 #include <utils/fileutils.h>
 #include <utils/hostosinfo.h>
@@ -1060,10 +1061,8 @@ static void addUnique(const Macros &newMacros, Macros &macros,
                       QSet<ProjectExplorer::Macro> &alreadyIn)
 {
     for (const ProjectExplorer::Macro &macro : newMacros) {
-        if (!alreadyIn.contains(macro)) {
+        if (Utils::insert(alreadyIn, macro))
             macros += macro;
-            alreadyIn.insert(macro);
-        }
     }
 }
 
@@ -1949,9 +1948,8 @@ void CppModelManager::GC()
         const FilePath filePath = todo.last();
         todo.removeLast();
 
-        if (reachableFiles.contains(filePath))
+        if (!Utils::insert(reachableFiles, filePath))
             continue;
-        reachableFiles.insert(filePath);
 
         if (Document::Ptr doc = currentSnapshot.document(filePath))
             todo += doc->includedFiles();

src/plugins/cppeditor/cppquickfixes.cpp

@@ -8342,14 +8342,13 @@ private:
         QList<Snapshot::IncludeLocation>
             includeLocationsOfDocument = refactoring.snapshot().includeLocationsOfDocument(filePath);
         for (Snapshot::IncludeLocation &loc : includeLocationsOfDocument) {
-            if (m_processed.contains(loc.first))
+            if (!Utils::insert(m_processed, loc.first))
                 continue;
 
             CppRefactoringFilePtr file = refactoring.file(loc.first->filePath());
             const bool noGlobalUsing = refactorFile(file,
                                                     refactoring.snapshot(),
                                                     file->position(loc.second, 1));
-            m_processed.insert(loc.first);
             if (noGlobalUsing)
                 processIncludes(refactoring, loc.first->filePath());
         }

src/plugins/cppeditor/cppsourceprocessor.cpp

@@ -9,6 +9,7 @@
 
 #include <coreplugin/editormanager/editormanager.h>
 
+#include <utils/algorithm.h>
 #include <utils/filepath.h>
 #include <utils/hostosinfo.h>
 #include <utils/qtcassert.h>
@@ -365,11 +366,9 @@ void CppSourceProcessor::mergeEnvironment(Document::Ptr doc)
 
     const QString fn = doc->filePath().path();
 
-    if (m_processed.contains(fn))
+    if (!Utils::insert(m_processed, fn))
         return;
 
-    m_processed.insert(fn);
-
     const QList<Document::Include> includes = doc->resolvedIncludes();
     for (const Document::Include &incl : includes) {
         const FilePath includedFile = incl.resolvedFileName();

src/plugins/cppeditor/typehierarchybuilder.cpp

@@ -5,6 +5,8 @@
 
 #include <cplusplus/FindUsages.h>
 
+#include <utils/algorithm.h>
+
 using namespace CPlusPlus;
 using namespace Utils;
 
@@ -170,11 +172,9 @@ void TypeHierarchyBuilder::buildDerived(const std::optional<QFuture<void>> &futu
                                         QHash<QString, QHash<QString, QString>> &cache)
 {
     Symbol *symbol = typeHierarchy->_symbol;
-    if (_visited.contains(symbol))
+    if (!Utils::insert(_visited, symbol))
         return;
 
-    _visited.insert(symbol);
-
     const QString &symbolName = _overview.prettyName(LookupContext::fullyQualifiedName(symbol));
     DerivedHierarchyVisitor visitor(symbolName, cache);
 

src/plugins/fakevim/fakevimplugin.cpp

@@ -45,6 +45,7 @@
 #include <texteditor/textmark.h>
 #include <texteditor/typingsettings.h>
 
+#include <utils/algorithm.h>
 #include <utils/aspects.h>
 #include <utils/fancylineedit.h>
 #include <utils/hostosinfo.h>
@@ -944,9 +945,8 @@ public:
             QString found = sel.selectedText();
             // Only add "real" completions.
             if (found.startsWith(needle)
-                    && !seen.contains(found)
+                    && sel.anchor() != basePosition
-                    && sel.anchor() != basePosition) {
+                    && Utils::insert(seen, found)) {
-                seen.insert(found);
                 auto item = new FakeVimAssistProposalItem(m_provider);
                 item->setText(found);
                 items.append(item);

src/plugins/glsleditor/glsleditor.cpp

@@ -269,11 +269,9 @@ void GlslEditorWidget::updateDocumentNow()
         for (const DiagnosticMessage &m : messages) {
             if (! m.line())
                 continue;
-            else if (errors.contains(m.line()))
+            if (!Utils::insert(errors, m.line()))
                 continue;
 
-            errors.insert(m.line());
-
             QTextCursor cursor(document()->findBlockByNumber(m.line() - 1));
             cursor.movePosition(QTextCursor::EndOfBlock, QTextCursor::KeepAnchor);
 

src/plugins/languageclient/semantichighlightsupport.cpp

@@ -10,6 +10,7 @@
 #include <texteditor/syntaxhighlighter.h>
 #include <texteditor/texteditor.h>
 #include <texteditor/texteditorsettings.h>
+#include <utils/algorithm.h>
 #include <utils/mimeutils.h>
 
 #include <QTextDocument>
@@ -165,9 +166,8 @@ void SemanticTokenSupport::updateSemanticTokensImpl(TextDocument *textDocument,
 
 void SemanticTokenSupport::queueDocumentReload(TextEditor::TextDocument *doc)
 {
-    if (m_docReloadQueue.contains(doc))
+    if (!Utils::insert(m_docReloadQueue, doc))
         return;
-    m_docReloadQueue << doc;
     connect(
         m_client,
         &Client::initialized,

src/plugins/macros/actionmacrohandler.cpp

@@ -13,6 +13,8 @@
 
 #include <texteditor/texteditorconstants.h>
 
+#include <utils/algorithm.h>
+
 #include <QAction>
 #include <QEvent>
 
@@ -55,8 +57,7 @@ bool ActionMacroHandler::executeEvent(const MacroEvent &macroEvent)
 
 void ActionMacroHandler::registerCommand(Id id)
 {
-    if (!m_commandIds.contains(id)) {
+    if (Utils::insert(m_commandIds, id)) {
-        m_commandIds.insert(id);
         const Command *command = ActionManager::command(id);
         if (QAction *action = command->action()) {
             connect(action, &QAction::triggered, this, [this, id, command]() {

src/plugins/modeleditor/modelindexer.cpp

@@ -21,6 +21,7 @@
 #include <projectexplorer/projectmanager.h>
 #include <projectexplorer/projectnodes.h>
 
+#include <utils/algorithm.h>
 #include <utils/mimeutils.h>
 #include <utils/qtcassert.h>
 
@@ -288,8 +289,7 @@ void ModelIndexer::IndexerThread::onFilesQueued()
             // collect all diagrams of model
             DiagramsCollectorVisitor visitor(indexedModel);
             project.rootPackage()->accept(&visitor);
-            if (m_indexer->d->defaultModelFiles.contains(queuedFile)) {
+            if (m_indexer->d->defaultModelFiles.remove(queuedFile)) {
-                m_indexer->d->defaultModelFiles.remove(queuedFile);
                 // check if model has a diagram which could be opened
                 qmt::FindRootDiagramVisitor diagramVisitor;
                 project.rootPackage()->accept(&diagramVisitor);
@@ -426,10 +426,9 @@ void ModelIndexer::scanProject(ProjectExplorer::Project *project)
         // queue files
         while (!filesQueue.isEmpty()) {
             QueuedFile queuedFile = filesQueue.takeFirst();
-            if (!d->queuedFilesSet.contains(queuedFile)) {
+            if (Utils::insert(d->queuedFilesSet, queuedFile)) {
                 QMT_CHECK(!d->filesQueue.contains(queuedFile));
                 d->filesQueue.append(queuedFile);
-                d->queuedFilesSet.insert(queuedFile);
                 filesAreQueued = true;
             }
         }
@@ -474,11 +473,10 @@ void ModelIndexer::forgetProject(ProjectExplorer::Project *project)
         const QString fileString = file.toString();
         // remove file from queue
         QueuedFile queuedFile(fileString, project);
-        if (d->queuedFilesSet.contains(queuedFile)) {
+        if (d->queuedFilesSet.remove(queuedFile)) {
             QMT_CHECK(d->filesQueue.contains(queuedFile));
             d->filesQueue.removeOne(queuedFile);
             QMT_CHECK(!d->filesQueue.contains(queuedFile));
-            d->queuedFilesSet.remove(queuedFile);
         }
         removeModelFile(fileString, project);
         removeDiagramReferenceFile(fileString, project);

src/plugins/projectexplorer/projectmodels.cpp

@@ -521,8 +521,7 @@ void FlatModel::addFolderNode(WrapperNode *parent, FolderNode *folderNode, QSet<
                     }
                 }
             }
-            if (!isHidden && !seen->contains(subFolderNode)) {
+            if (!isHidden && Utils::insert(*seen, subFolderNode)) {
-                seen->insert(subFolderNode);
                 auto node = new WrapperNode(subFolderNode);
                 parent->appendChild(node);
                 addFolderNode(node, subFolderNode, seen);
@@ -531,10 +530,8 @@ void FlatModel::addFolderNode(WrapperNode *parent, FolderNode *folderNode, QSet<
                 addFolderNode(parent, subFolderNode, seen);
             }
         } else if (FileNode *fileNode = node->asFileNode()) {
-            if (!seen->contains(fileNode)) {
+            if (Utils::insert(*seen, fileNode))
-                seen->insert(fileNode);
                 parent->appendChild(new WrapperNode(fileNode));
-            }
         }
     }
 

src/plugins/python/pythonproject.cpp

@@ -131,10 +131,9 @@ static QStringList readLines(const FilePath &projectFile)
             const QString line = stream.readLine();
             if (line.isNull())
                 break;
-            if (visited.contains(line))
+            if (!Utils::insert(visited, line))
                 continue;
             lines.append(line);
-            visited.insert(line);
         }
     }
 
@@ -149,10 +148,8 @@ static QStringList readLinesJson(const FilePath &projectFile, QString *errorMess
     const QJsonObject obj = readObjJson(projectFile, errorMessage);
     for (const QJsonValue &file : obj.value("files").toArray()) {
         const QString fileName = file.toString();
-        if (visited.contains(fileName))
+        if (Utils::insert(visited, fileName))
-            continue;
+            lines.append(fileName);
-        lines.append(fileName);
-        visited.insert(fileName);
     }
 
     return lines;

src/plugins/qbsprojectmanager/qbsprojectimporter.cpp

@@ -17,6 +17,7 @@
 #include <projectexplorer/projectexplorerconstants.h>
 #include <projectexplorer/toolchain.h>
 #include <qtsupport/qtkitinformation.h>
+#include <utils/algorithm.h>
 #include <utils/filepath.h>
 #include <utils/hostosinfo.h>
 
@@ -100,10 +101,8 @@ FilePaths QbsProjectImporter::importCandidates()
     for (Kit * const k : kits) {
         FilePath bdir = buildDir(projectFilePath(), k);
         const FilePath candidate = bdir.absolutePath();
-        if (!seenCandidates.contains(candidate)) {
+        if (Utils::insert(seenCandidates, candidate))
-            seenCandidates.insert(candidate);
             candidates << candidatesForDirectory(candidate);
-        }
     }
     qCDebug(qbsPmLog) << "build directory candidates:" << candidates;
     return candidates;

src/plugins/qmljseditor/qmljscompletionassist.cpp

@@ -16,6 +16,7 @@
 #include <texteditor/texteditorsettings.h>
 #include <texteditor/completionsettings.h>
 
+#include <utils/algorithm.h>
 #include <utils/qtcassert.h>
 
 #include <qmljs/qmljsmodelmanagerinterface.h>
@@ -261,10 +262,9 @@ private:
 
     void processProperties(const ObjectValue *object)
     {
-        if (! object || _processed.contains(object))
+        if (! object || !Utils::insert(_processed, object))
             return;
 
-        _processed.insert(object);
         processProperties(object->prototype(_scopeChain->context()));
 
         _currentObject = object;

src/plugins/qmljseditor/qmljsfindreferences.cpp

@@ -952,9 +952,8 @@ QList<FindReferences::Usage> FindReferences::findUsageOfType(const Utils::FilePa
     QSet<Utils::FilePath> docDone;
     for (const QmlJS::Document::Ptr &doc : std::as_const(snapshot)) {
         Utils::FilePath sourceFile = modelManager->fileToSource(doc->fileName());
-        if (docDone.contains(sourceFile))
+        if (!Utils::insert(docDone, sourceFile))
             continue;
-        docDone.insert(sourceFile);
         QmlJS::Document::Ptr sourceDoc = doc;
         if (sourceFile != doc->fileName())
             sourceDoc = snapshot.document(sourceFile);

src/plugins/qtsupport/qtoptionspage.cpp

@@ -533,10 +533,8 @@ QList<ToolChain*> QtOptionsPageWidget::toolChains(const QtVersion *version)
     for (const Abi &a : abis) {
         const Toolchains tcList = ToolChainManager::findToolChains(a);
         for (ToolChain *tc : tcList) {
-            if (ids.contains(tc->id()))
+            if (Utils::insert(ids, tc->id()))
-                continue;
+                toolChains.append(tc);
-            ids.insert(tc->id());
-            toolChains.append(tc);
         }
     }
 

src/plugins/squish/squishresultmodel.cpp

@@ -139,9 +139,7 @@ void SquishResultFilterModel::enableAllResultTypes()
 
 void SquishResultFilterModel::toggleResultType(Result::Type type)
 {
-    if (m_enabled.contains(type))
+    if (!m_enabled.remove(type))
-        m_enabled.remove(type);
-    else
         m_enabled.insert(type);
     invalidateFilter();
 }

src/plugins/texteditor/basefilefind.cpp

@@ -570,9 +570,8 @@ FilePaths BaseFileFind::replaceAll(const QString &text, const SearchResultItems
         QSet<QPair<int, int>> processed;
         for (const SearchResultItem &item : changeItems) {
             const QPair<int, int> p{item.mainRange().begin.line, item.mainRange().begin.column};
-            if (processed.contains(p))
+            if (!Utils::insert(processed, p))
                 continue;
-            processed.insert(p);
 
             QString replacement;
             if (item.userData().canConvert<QStringList>() && !item.userData().toStringList().isEmpty()) {

src/plugins/texteditor/codeassist/documentcontentcompletion.cpp

@@ -96,11 +96,10 @@ IAssistProposal *DocumentContentCompletionProcessor::performAsync()
                 continue;
         }
 
-        if (!words.contains(word)) {
+        if (Utils::insert(words, word)) {
             auto item = new AssistProposalItem();
             item->setText(word);
             items.append(item);
-            words.insert(word);
         }
     }
 

src/plugins/texteditor/texteditor.cpp

@@ -4416,9 +4416,8 @@ void TextEditorWidgetPrivate::paintCurrentLineHighlight(const PaintEventData &da
     QSet<int> seenLines;
     for (const QTextCursor &cursor : cursorsForBlock) {
         QTextLine line = data.block.layout()->lineForTextPosition(cursor.positionInBlock());
-        if (seenLines.contains(line.lineNumber()))
+        if (!Utils::insert(seenLines, line.lineNumber()))
             continue;
-        seenLines << line.lineNumber();
         QRectF lineRect = line.rect();
         lineRect.moveTop(lineRect.top() + blockRect.top());
         lineRect.setLeft(0);
@@ -5657,10 +5656,8 @@ void TextEditorWidgetPrivate::slotUpdateBlockNotify(const QTextBlock &block)
             if (blockContainsFindScope) {
                 QTextBlock b = block.document()->findBlock(scope.selectionStart());
                 do {
-                    if (!updatedBlocks.contains(b.blockNumber())) {
+                    if (Utils::insert(updatedBlocks, b.blockNumber()))
-                        updatedBlocks << b.blockNumber();
                         emit q->requestBlockUpdate(b);
-                    }
                     b = b.next();
                 } while (b.isValid() && b.position() < scope.selectionEnd());
             }