CPlusPlus: Use FilePath for resolved include paths

... and fix fallout.

Change-Id: I66886e91ff476eff15db51cc024a8021e952d44d
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>

25 files changed, 136 insertions, 124 deletions

diff --git a/src/libs/cplusplus/CppDocument.cpp b/src/libs/cplusplus/CppDocument.cpp
index 5167e9ad2c..ac4986fb1a 100644
--- a/src/libs/cplusplus/CppDocument.cpp
+++ b/src/libs/cplusplus/CppDocument.cpp
@@ -299,11 +299,11 @@ void Document::setLastModified(const QDateTime &lastModified)
 
 FilePaths Document::includedFiles() const
 {
-    QStringList files;
+    FilePaths files;
     for (const Include &i : std::as_const(_resolvedIncludes))
         files.append(i.resolvedFileName());
-    files.removeDuplicates();
-    return transform(files, &FilePath::fromString);
+    FilePath::removeDuplicates(files);
+    return files;
 }
 
 // This assumes to be called with a QDir::cleanPath cleaned fileName.
@@ -786,13 +786,13 @@ QSet<FilePath> Snapshot::allIncludesForDocument(const FilePath &filePath) const
 }
 
 QList<Snapshot::IncludeLocation> Snapshot::includeLocationsOfDocument(
-        const QString &fileNameOrPath) const
+        const FilePath &fileNameOrPath) const
 {
-    const bool matchFullPath = FilePath::fromString(fileNameOrPath).isAbsolutePath();
+    const bool matchFullPath = fileNameOrPath.isAbsolutePath();
     const auto isMatch = [&](const Document::Include &include) {
         if (matchFullPath)
             return include.resolvedFileName() == fileNameOrPath;
-        return FilePath::fromString(include.resolvedFileName()).fileName() == fileNameOrPath;
+        return include.resolvedFileName().fileName() == fileNameOrPath.fileName();
     };
     QList<IncludeLocation> result;
     for (const_iterator cit = begin(), citEnd = end(); cit != citEnd; ++cit) {
@@ -807,7 +807,7 @@ QList<Snapshot::IncludeLocation> Snapshot::includeLocationsOfDocument(
         }
         if (!matchFullPath && !foundMatch) {
             for (const auto &includeFile : cit.value()->unresolvedIncludes()) {
-                if (includeFile.unresolvedFileName() == fileNameOrPath)
+                if (includeFile.unresolvedFileName() == fileNameOrPath.path())
                     result.push_back({doc, includeFile.line()});
             }
         }
diff --git a/src/libs/cplusplus/CppDocument.h b/src/libs/cplusplus/CppDocument.h
index 599b8cbc71..44d880ccf6 100644
--- a/src/libs/cplusplus/CppDocument.h
+++ b/src/libs/cplusplus/CppDocument.h
@@ -218,13 +218,13 @@ public:
     };
 
     class Include {
-        QString _resolvedFileName;
+        Utils::FilePath _resolvedFileName;
         QString _unresolvedFileName;
         int _line;
         Client::IncludeType _type;
 
     public:
-        Include(const QString &unresolvedFileName, const QString &resolvedFileName, int line,
+        Include(const QString &unresolvedFileName, const Utils::FilePath &resolvedFileName, int line,
                 Client::IncludeType type)
             : _resolvedFileName(resolvedFileName)
             , _unresolvedFileName(unresolvedFileName)
@@ -232,7 +232,7 @@ public:
             , _type(type)
         { }
 
-        const QString &resolvedFileName() const
+        const Utils::FilePath &resolvedFileName() const
         { return _resolvedFileName; }
 
         const QString &unresolvedFileName() const
@@ -404,7 +404,7 @@ public:
 
     QSet<Utils::FilePath> allIncludesForDocument(const Utils::FilePath &filePath) const;
 
-    QList<IncludeLocation> includeLocationsOfDocument(const QString &fileNameOrPath) const;
+    QList<IncludeLocation> includeLocationsOfDocument(const Utils::FilePath &fileNameOrPath) const;
 
     Utils::FilePaths filesDependingOn(const Utils::FilePath &filePath) const;
 
diff --git a/src/libs/cplusplus/FastPreprocessor.cpp b/src/libs/cplusplus/FastPreprocessor.cpp
index c948776c4b..8cc01e6250 100644
--- a/src/libs/cplusplus/FastPreprocessor.cpp
+++ b/src/libs/cplusplus/FastPreprocessor.cpp
@@ -29,11 +29,11 @@ QByteArray FastPreprocessor::run(Document::Ptr newDoc,
     _preproc.setKeepComments(true);
 
     if (Document::Ptr doc = _snapshot.document(filePath)) {
-        _merged.insert(filePath.toString());
+        _merged.insert(filePath);
 
         for (Snapshot::const_iterator i = _snapshot.begin(), ei = _snapshot.end(); i != ei; ++i) {
             if (isInjectedFile(i.key().toString()))
-                mergeEnvironment(i.key().toString());
+                mergeEnvironment(i.key());
         }
 
         const QList<Document::Include> includes = doc->resolvedIncludes();
@@ -55,20 +55,21 @@ void FastPreprocessor::sourceNeeded(int line, const QString &fileName, IncludeTy
 {
     Q_UNUSED(initialIncludes)
     Q_ASSERT(_currentDoc);
+    FilePath filePath = FilePath::fromString(fileName);
     if (_addIncludesToCurrentDoc) {
-        // CHECKME: Is that cleanName needed?
-        const QString cleanName = QDir::cleanPath(fileName);
-        _currentDoc->addIncludeFile(Document::Include(fileName, cleanName, line, mode));
+        // CHECKME: Is that cleanPath needed?
+        const FilePath cleanPath = filePath.cleanPath();
+        _currentDoc->addIncludeFile(Document::Include(fileName, cleanPath, line, mode));
     }
-    mergeEnvironment(fileName);
+    mergeEnvironment(filePath);
 }
 
-void FastPreprocessor::mergeEnvironment(const QString &fileName)
+void FastPreprocessor::mergeEnvironment(const FilePath &filePath)
 {
-    if (! _merged.contains(fileName)) {
-        _merged.insert(fileName);
+    if (! _merged.contains(filePath)) {
+        _merged.insert(filePath);
 
-        if (Document::Ptr doc = _snapshot.document(fileName)) {
+        if (Document::Ptr doc = _snapshot.document(filePath)) {
             const QList<Document::Include> includes = doc->resolvedIncludes();
             for (const Document::Include &i : includes)
                 mergeEnvironment(i.resolvedFileName());
diff --git a/src/libs/cplusplus/FastPreprocessor.h b/src/libs/cplusplus/FastPreprocessor.h
index 0892e120b4..c4f30063fa 100644
--- a/src/libs/cplusplus/FastPreprocessor.h
+++ b/src/libs/cplusplus/FastPreprocessor.h
@@ -3,12 +3,15 @@
 
 #pragma once
 
-#include "PreprocessorClient.h"
 #include "CppDocument.h"
-#include "pp.h"
+#include "PreprocessorClient.h"
+#include "PreprocessorEnvironment.h"
+#include "pp-engine.h"
 
 #include <cplusplus/Control.h>
 
+#include <utils/filepath.h>
+
 #include <QSet>
 #include <QString>
 
@@ -19,11 +22,11 @@ class CPLUSPLUS_EXPORT FastPreprocessor: public Client
     Environment _env;
     Snapshot _snapshot;
     Preprocessor _preproc;
-    QSet<QString> _merged;
+    QSet<Utils::FilePath> _merged;
     Document::Ptr _currentDoc;
     bool _addIncludesToCurrentDoc;
 
-    void mergeEnvironment(const QString &fileName);
+    void mergeEnvironment(const Utils::FilePath &filePath);
 
 public:
     FastPreprocessor(const Snapshot &snapshot);
diff --git a/src/plugins/autotest/boost/boosttestparser.cpp b/src/plugins/autotest/boost/boosttestparser.cpp
index c3cde92fa0..2a514c8b9d 100644
--- a/src/plugins/autotest/boost/boosttestparser.cpp
+++ b/src/plugins/autotest/boost/boosttestparser.cpp
@@ -55,7 +55,7 @@ static bool includesBoostTest(const CPlusPlus::Document::Ptr &doc,
 {
     static const QRegularExpression boostTestHpp("^.*/boost/test/.*\\.hpp$");
     for (const CPlusPlus::Document::Include &inc : doc->resolvedIncludes()) {
-        if (boostTestHpp.match(inc.resolvedFileName()).hasMatch())
+        if (boostTestHpp.match(inc.resolvedFileName().path()).hasMatch())
             return true;
     }
 
diff --git a/src/plugins/cppeditor/cppcodegen_test.cpp b/src/plugins/cppeditor/cppcodegen_test.cpp
index 72e702d89c..49522e8cb0 100644
--- a/src/plugins/cppeditor/cppcodegen_test.cpp
+++ b/src/plugins/cppeditor/cppcodegen_test.cpp
@@ -388,7 +388,7 @@ void CodegenTest::testDefinitionFirstMember()
     Document::Ptr sourceDocument = createDocumentAndFile(&temporaryDir, "file.cpp", sourceText, 3);
     QVERIFY(sourceDocument);
     sourceDocument->addIncludeFile(Document::Include(QLatin1String("file.h"),
-                                                     headerDocument->filePath().toString(), 1,
+                                                     headerDocument->filePath(), 1,
                                                      Client::IncludeLocal));
 
     Snapshot snapshot;
@@ -447,7 +447,7 @@ void CodegenTest::testDefinitionLastMember()
     Document::Ptr sourceDocument = createDocumentAndFile(&temporaryDir, "file.cpp", sourceText, 3);
     QVERIFY(sourceDocument);
     sourceDocument->addIncludeFile(Document::Include(QLatin1String("file.h"),
-                                                     headerDocument->filePath().toString(), 1,
+                                                     headerDocument->filePath(), 1,
                                                      Client::IncludeLocal));
 
     Snapshot snapshot;
@@ -513,7 +513,7 @@ void CodegenTest::testDefinitionMiddleMember()
     Document::Ptr sourceDocument = createDocumentAndFile(&temporaryDir, "file.cpp", sourceText, 4);
     QVERIFY(sourceDocument);
     sourceDocument->addIncludeFile(Document::Include(QLatin1String("file.h"),
-                                                     headerDocument->filePath().toString(), 1,
+                                                     headerDocument->filePath(), 1,
                                                      Client::IncludeLocal));
 
     Snapshot snapshot;
@@ -573,7 +573,7 @@ void CodegenTest::testDefinitionMiddleMemberSurroundedByUndefined()
     Document::Ptr sourceDocument = createDocumentAndFile(&temporaryDir, "file.cpp", sourceText, 3);
     QVERIFY(sourceDocument);
     sourceDocument->addIncludeFile(Document::Include(QLatin1String("file.h"),
-                                                     headerDocument->filePath().toString(), 1,
+                                                     headerDocument->filePath(), 1,
                                                      Client::IncludeLocal));
 
     Snapshot snapshot;
@@ -636,7 +636,7 @@ void CodegenTest::testDefinitionMemberSpecificFile()
     Document::Ptr sourceDocument = createDocumentAndFile(&temporaryDir, "file.cpp", sourceText, 3);
     QVERIFY(sourceDocument);
     sourceDocument->addIncludeFile(Document::Include(QLatin1String("file.h"),
-                                                     headerDocument->filePath().toString(), 1,
+                                                     headerDocument->filePath(), 1,
                                                      Client::IncludeLocal));
 
     Snapshot snapshot;
diff --git a/src/plugins/cppeditor/cppcodemodelinspectordialog.cpp b/src/plugins/cppeditor/cppcodemodelinspectordialog.cpp
index 1f2349f113..b8af9a2b1b 100644
--- a/src/plugins/cppeditor/cppcodemodelinspectordialog.cpp
+++ b/src/plugins/cppeditor/cppcodemodelinspectordialog.cpp
@@ -588,7 +588,7 @@ QVariant IncludesModel::data(const QModelIndex &index, int role) const
     static const QBrush redBrush(QColor(205, 38, 38));
 
     const Document::Include include = m_includes.at(index.row());
-    const QString resolvedFileName = QDir::toNativeSeparators(include.resolvedFileName());
+    const FilePath resolvedFileName = include.resolvedFileName();
     const bool isResolved = !resolvedFileName.isEmpty();
 
     if (role == Qt::DisplayRole) {
@@ -599,7 +599,7 @@ QVariant IncludesModel::data(const QModelIndex &index, int role) const
             return include.line();
         } else if (column == FilePathsColumn) {
             return QVariant(CMI::Utils::unresolvedFileNameWithDelimiters(include)
-                            + QLatin1String(" --> ") + resolvedFileName);
+                            + QLatin1String(" --> ") + resolvedFileName.toUserOutput());
         }
     } else if (role == Qt::ForegroundRole) {
         return isResolved ? greenBrush : redBrush;
diff --git a/src/plugins/cppeditor/cppcompletionassist.cpp b/src/plugins/cppeditor/cppcompletionassist.cpp
index 0e68454d09..649a0b5ad9 100644
--- a/src/plugins/cppeditor/cppcompletionassist.cpp
+++ b/src/plugins/cppeditor/cppcompletionassist.cpp
@@ -1479,8 +1479,8 @@ bool InternalCppCompletionAssistProcessor::globalCompletion(Scope *currentScope)
         completeNamespace(b);
 
     addKeywords();
-    addMacros(CppModelManager::configurationFileName().path(), context.snapshot());
-    addMacros(context.thisDocument()->filePath().toString(), context.snapshot());
+    addMacros(CppModelManager::configurationFileName(), context.snapshot());
+    addMacros(context.thisDocument()->filePath(), context.snapshot());
     addSnippets();
     return !m_completions.isEmpty();
 }
@@ -1841,29 +1841,29 @@ void InternalCppCompletionAssistProcessor::addKeywords()
     }
 }
 
-void InternalCppCompletionAssistProcessor::addMacros(const QString &fileName,
+void InternalCppCompletionAssistProcessor::addMacros(const Utils::FilePath &filePath,
                                                      const Snapshot &snapshot)
 {
-    QSet<QString> processed;
+    QSet<Utils::FilePath> processed;
     QSet<QString> definedMacros;
 
-    addMacros_helper(snapshot, fileName, &processed, &definedMacros);
+    addMacros_helper(snapshot, filePath, &processed, &definedMacros);
 
     for (const QString &macroName : std::as_const(definedMacros))
         addCompletionItem(macroName, Icons::macroIcon(), MacrosOrder);
 }
 
 void InternalCppCompletionAssistProcessor::addMacros_helper(const Snapshot &snapshot,
-                                                    const QString &fileName,
-                                                    QSet<QString> *processed,
+                                                    const Utils::FilePath &filePath,
+                                                    QSet<Utils::FilePath> *processed,
                                                     QSet<QString> *definedMacros)
 {
-    Document::Ptr doc = snapshot.document(fileName);
+    Document::Ptr doc = snapshot.document(filePath);
 
-    if (!doc || processed->contains(doc->filePath().path()))
+    if (!doc || processed->contains(doc->filePath()))
         return;
 
-    processed->insert(doc->filePath().path());
+    processed->insert(doc->filePath());
 
     const QList<Document::Include> includes = doc->resolvedIncludes();
     for (const Document::Include &i : includes)
diff --git a/src/plugins/cppeditor/cppcompletionassist.h b/src/plugins/cppeditor/cppcompletionassist.h
index fbfdd209ca..4d986bb114 100644
--- a/src/plugins/cppeditor/cppcompletionassist.h
+++ b/src/plugins/cppeditor/cppcompletionassist.h
@@ -122,10 +122,10 @@ private:
     void addCompletionItem(CPlusPlus::Symbol *symbol,
                            int order = 0);
     void addKeywords();
-    void addMacros(const QString &fileName, const CPlusPlus::Snapshot &snapshot);
+    void addMacros(const Utils::FilePath &filePath, const CPlusPlus::Snapshot &snapshot);
     void addMacros_helper(const CPlusPlus::Snapshot &snapshot,
-                          const QString &fileName,
-                          QSet<QString> *processed,
+                          const Utils::FilePath &filePath,
+                          QSet<Utils::FilePath> *processed,
                           QSet<QString> *definedMacros);
 
     enum {
diff --git a/src/plugins/cppeditor/cppelementevaluator.cpp b/src/plugins/cppeditor/cppelementevaluator.cpp
index e835e0443b..225bfe44b7 100644
--- a/src/plugins/cppeditor/cppelementevaluator.cpp
+++ b/src/plugins/cppeditor/cppelementevaluator.cpp
@@ -21,6 +21,7 @@
 #include <QSet>
 
 using namespace CPlusPlus;
+using namespace Utils;
 
 namespace CppEditor::Internal {
 
@@ -62,18 +63,18 @@ class CppInclude : public CppElement
 {
 public:
     explicit CppInclude(const Document::Include &includeFile)
-        : path(QDir::toNativeSeparators(includeFile.resolvedFileName()))
-        , fileName(Utils::FilePath::fromString(includeFile.resolvedFileName()).fileName())
+        : path(includeFile.resolvedFileName())
+        , fileName(path.fileName())
     {
         helpCategory = Core::HelpItem::Brief;
         helpIdCandidates = QStringList(fileName);
         helpMark = fileName;
-        link = Utils::Link(Utils::FilePath::fromString(path));
-        tooltip = path;
+        link = Utils::Link(path);
+        tooltip = path.toUserOutput();
     }
 
 public:
-    QString path;
+    Utils::FilePath path;
     QString fileName;
 };
 
@@ -95,7 +96,7 @@ public:
 CppDeclarableElement::CppDeclarableElement(Symbol *declaration)
     : CppElement()
     , declaration(declaration)
-    , icon(Icons::iconForSymbol(declaration))
+    , icon(CPlusPlus::Icons::iconForSymbol(declaration))
 {
     Overview overview;
     overview.showArgumentNames = true;
diff --git a/src/plugins/cppeditor/cppfollowsymbolundercursor.cpp b/src/plugins/cppeditor/cppfollowsymbolundercursor.cpp
index 78bff45329..9a73448bd5 100644
--- a/src/plugins/cppeditor/cppfollowsymbolundercursor.cpp
+++ b/src/plugins/cppeditor/cppfollowsymbolundercursor.cpp
@@ -624,7 +624,7 @@ void FollowSymbolUnderCursor::findLink(
             const QList<Document::Include> includes = doc->resolvedIncludes();
             for (const Document::Include &incl : includes) {
                 if (incl.line() == lineno) {
-                    link.targetFilePath = Utils::FilePath::fromString(incl.resolvedFileName());
+                    link.targetFilePath = incl.resolvedFileName();
                     link.linkTextStart = beginOfToken + 1;
                     link.linkTextEnd = endOfToken - 1;
                     processLinkCallback(link);
diff --git a/src/plugins/cppeditor/cppincludehierarchy.cpp b/src/plugins/cppeditor/cppincludehierarchy.cpp
index d9211aebed..6f6a878109 100644
--- a/src/plugins/cppeditor/cppincludehierarchy.cpp
+++ b/src/plugins/cppeditor/cppincludehierarchy.cpp
@@ -58,24 +58,24 @@ static Snapshot globalSnapshot()
 struct FileAndLine
 {
     FileAndLine() = default;
-    FileAndLine(const QString &f, int l) : file(f), line(l) {}
+    FileAndLine(const FilePath &f, int l) : file(f), line(l) {}
 
-    QString file;
+    FilePath file;
     int line = 0;
 };
 
 using FileAndLines = QList<FileAndLine>;
 
-static FileAndLines findIncluders(const QString &filePath)
+static FileAndLines findIncluders(const FilePath &filePath)
 {
     FileAndLines result;
     const Snapshot snapshot = globalSnapshot();
     for (auto cit = snapshot.begin(), citEnd = snapshot.end(); cit != citEnd; ++cit) {
-        const QString filePathFromSnapshot = cit.key().toString();
+        const FilePath filePathFromSnapshot = cit.key();
         Document::Ptr doc = cit.value();
         const QList<Document::Include> resolvedIncludes = doc->resolvedIncludes();
         for (const auto &includeFile : resolvedIncludes) {
-            const QString includedFilePath = includeFile.resolvedFileName();
+            const FilePath includedFilePath = includeFile.resolvedFileName();
             if (includedFilePath == filePath)
                 result.append(FileAndLine(filePathFromSnapshot, int(includeFile.line())));
         }
@@ -83,7 +83,7 @@ static FileAndLines findIncluders(const QString &filePath)
     return result;
 }
 
-static FileAndLines findIncludes(const QString &filePath, const Snapshot &snapshot)
+static FileAndLines findIncludes(const FilePath &filePath, const Snapshot &snapshot)
 {
     FileAndLines result;
     if (Document::Ptr doc = snapshot.document(filePath)) {
@@ -101,11 +101,11 @@ public:
     enum SubTree { RootItem, InIncludes, InIncludedBy };
     CppIncludeHierarchyItem() = default;
 
-    void createChild(const QString &filePath, SubTree subTree,
+    void createChild(const FilePath &filePath, SubTree subTree,
                      int line = 0, bool definitelyNoChildren = false)
     {
         auto item = new CppIncludeHierarchyItem;
-        item->m_fileName = filePath.mid(filePath.lastIndexOf('/') + 1);
+        item->m_fileName = filePath.fileName();
         item->m_filePath = filePath;
         item->m_line = line;
         item->m_subTree = subTree;
@@ -120,7 +120,7 @@ public:
             item->setChildrenChecked();
     }
 
-    QString filePath() const
+    FilePath filePath() const
     {
         return isPhony() ? model()->editorFilePath() : m_filePath;
     }
@@ -138,7 +138,7 @@ private:
 
     Qt::ItemFlags flags(int) const override
     {
-        const Utils::Link link(Utils::FilePath::fromString(m_filePath), m_line);
+        const Utils::Link link(m_filePath, m_line);
         if (link.hasValidTarget())
             return Qt::ItemIsDragEnabled | Qt::ItemIsEnabled | Qt::ItemIsSelectable;
         return Qt::ItemIsEnabled | Qt::ItemIsSelectable;
@@ -148,7 +148,7 @@ private:
     void fetchMore() override;
 
     QString m_fileName;
-    QString m_filePath;
+    FilePath m_filePath;
     int m_line = 0;
     SubTree m_subTree = RootItem;
     bool m_isCyclic = false;
@@ -171,11 +171,11 @@ QVariant CppIncludeHierarchyItem::data(int column, int role) const
 
     switch (role) {
         case Qt::ToolTipRole:
-            return m_filePath;
+            return m_filePath.displayName();
         case Qt::DecorationRole:
-            return FileIconProvider::icon(FilePath::fromString(m_filePath));
+            return FileIconProvider::icon(m_filePath);
         case LinkRole:
-            return QVariant::fromValue(Link(FilePath::fromString(m_filePath), m_line));
+            return QVariant::fromValue(Link(m_filePath, m_line));
     }
 
     return QVariant();
@@ -197,7 +197,7 @@ void CppIncludeHierarchyItem::fetchMore()
 
     model()->m_seen.insert(m_filePath);
 
-    const FilePath editorFilePath = FilePath::fromString(model()->editorFilePath());
+    const FilePath editorFilePath = model()->editorFilePath();
 
     setChildrenChecked();
     if (m_subTree == InIncludes) {
@@ -220,12 +220,14 @@ void CppIncludeHierarchyItem::fetchMore()
     }
 }
 
-void CppIncludeHierarchyModel::buildHierarchy(const QString &document)
+void CppIncludeHierarchyModel::buildHierarchy(const FilePath &document)
 {
     m_editorFilePath = document;
     rootItem()->removeChildren();
-    rootItem()->createChild(tr("Includes"), CppIncludeHierarchyItem::InIncludes);
-    rootItem()->createChild(tr("Included by"), CppIncludeHierarchyItem::InIncludedBy);
+    rootItem()->createChild(FilePath::fromPathPart(tr("Includes")),
+                            CppIncludeHierarchyItem::InIncludes);
+    rootItem()->createChild(FilePath::fromPathPart(tr("Included by")),
+                            CppIncludeHierarchyItem::InIncludedBy);
 }
 
 void CppIncludeHierarchyModel::setSearching(bool on)
@@ -411,7 +413,7 @@ void CppIncludeHierarchyWidget::perform()
         return;
 
     const Utils::FilePath documentPath = m_editor->textDocument()->filePath();
-    m_model.buildHierarchy(documentPath.toString());
+    m_model.buildHierarchy(documentPath);
 
     m_inspectedFile->setText(m_editor->textDocument()->displayName());
     m_inspectedFile->setLink(Utils::Link(documentPath));
diff --git a/src/plugins/cppeditor/cppincludehierarchy.h b/src/plugins/cppeditor/cppincludehierarchy.h
index ff1693755c..a9712ce73b 100644
--- a/src/plugins/cppeditor/cppincludehierarchy.h
+++ b/src/plugins/cppeditor/cppincludehierarchy.h
@@ -25,8 +25,8 @@ public:
     QStringList mimeTypes() const override;
     QMimeData *mimeData(const QModelIndexList &indexes) const override;
 
-    void buildHierarchy(const QString &filePath);
-    QString editorFilePath() const { return m_editorFilePath; }
+    void buildHierarchy(const Utils::FilePath &filePath);
+    const Utils::FilePath &editorFilePath() const { return m_editorFilePath; }
     void setSearching(bool on);
     QString toString() const;
 
@@ -37,8 +37,8 @@ public:
 
 private:
     friend class CppIncludeHierarchyItem;
-    QString m_editorFilePath;
-    QSet<QString> m_seen;
+    Utils::FilePath m_editorFilePath;
+    QSet<Utils::FilePath> m_seen;
     bool m_searching = false;
 };
 
diff --git a/src/plugins/cppeditor/cppincludehierarchy_test.cpp b/src/plugins/cppeditor/cppincludehierarchy_test.cpp
index d3d0bf0397..a895341d51 100644
--- a/src/plugins/cppeditor/cppincludehierarchy_test.cpp
+++ b/src/plugins/cppeditor/cppincludehierarchy_test.cpp
@@ -82,7 +82,7 @@ public:
 
         // Test model
         CppIncludeHierarchyModel model;
-        model.buildHierarchy(editor->document()->filePath().toString());
+        model.buildHierarchy(editor->document()->filePath());
         const QString actualHierarchy = toString(model);
         QCOMPARE(actualHierarchy, expectedHierarchy);
     }
diff --git a/src/plugins/cppeditor/cppmodelmanager.cpp b/src/plugins/cppeditor/cppmodelmanager.cpp
index cce4594704..1f22b3e08b 100644
--- a/src/plugins/cppeditor/cppmodelmanager.cpp
+++ b/src/plugins/cppeditor/cppmodelmanager.cpp
@@ -1794,7 +1794,7 @@ void CppModelManager::renameIncludes(const Utils::FilePath &oldFilePath,
         return;
 
     const QList<Snapshot::IncludeLocation> locations = snapshot().includeLocationsOfDocument(
-        isUiFile ? oldFileName : oldFilePath.toString());
+        isUiFile ? FilePath::fromString(oldFileName) : oldFilePath);
     for (const Snapshot::IncludeLocation &loc : locations) {
         const FilePath filePath = loc.first->filePath();
 
diff --git a/src/plugins/cppeditor/cppquickfixes.cpp b/src/plugins/cppeditor/cppquickfixes.cpp
index 91181b91f5..46a31e1a87 100644
--- a/src/plugins/cppeditor/cppquickfixes.cpp
+++ b/src/plugins/cppeditor/cppquickfixes.cpp
@@ -8031,7 +8031,7 @@ private:
             Node &node = includeGraph[filePath];
             node.document = doc;
             for (const Document::Include &include : doc->resolvedIncludes()) {
-                const auto filePath = FilePath::fromString(include.resolvedFileName());
+                const FilePath filePath = include.resolvedFileName();
                 if (shouldHandle(filePath)) {
                     Node &includedNode = includeGraph[filePath];
                     includedNode.includedBy.push_back(node);
@@ -8105,7 +8105,7 @@ private:
                                 refactoring.snapshot(),
                                 currentFile->endOf(m_usingDirective),
                                 true)) {
-            processIncludes(refactoring, filePath().toString());
+            processIncludes(refactoring, filePath());
         }
 
         for (auto &file : std::as_const(m_changes))
@@ -8143,10 +8143,10 @@ private:
         return visitor.isGlobalUsingNamespace() && !visitor.foundGlobalUsingNamespace();
     }
 
-    void processIncludes(CppRefactoringChanges &refactoring, const QString &fileName)
+    void processIncludes(CppRefactoringChanges &refactoring, const FilePath &filePath)
     {
         QList<Snapshot::IncludeLocation>
-            includeLocationsOfDocument = refactoring.snapshot().includeLocationsOfDocument(fileName);
+            includeLocationsOfDocument = refactoring.snapshot().includeLocationsOfDocument(filePath);
         for (Snapshot::IncludeLocation &loc : includeLocationsOfDocument) {
             if (m_processed.contains(loc.first))
                 continue;
@@ -8157,7 +8157,7 @@ private:
                                                     file->position(loc.second, 1));
             m_processed.insert(loc.first);
             if (noGlobalUsing)
-                processIncludes(refactoring, loc.first->filePath().toString());
+                processIncludes(refactoring, loc.first->filePath());
         }
     }
 
diff --git a/src/plugins/cppeditor/cppsourceprocessertesthelper.cpp b/src/plugins/cppeditor/cppsourceprocessertesthelper.cpp
index df55e8b159..bf166625d3 100644
--- a/src/plugins/cppeditor/cppsourceprocessertesthelper.cpp
+++ b/src/plugins/cppeditor/cppsourceprocessertesthelper.cpp
@@ -3,8 +3,12 @@
 
 #include "cppsourceprocessertesthelper.h"
 
+#include <utils/filepath.h>
+
 #include <QDir>
 
+using namespace Utils;
+
 namespace CppEditor::Tests::Internal {
 
 QString TestIncludePaths::includeBaseDirectory()
@@ -28,9 +32,9 @@ QString TestIncludePaths::directoryOfTestFile()
     return QDir::cleanPath(includeBaseDirectory() + QLatin1String("/local"));
 }
 
-QString TestIncludePaths::testFilePath(const QString &fileName)
+FilePath TestIncludePaths::testFilePath(const QString &fileName)
 {
-    return directoryOfTestFile() + QLatin1Char('/') + fileName;
+    return FilePath::fromString(directoryOfTestFile()) / fileName;
 }
 
-} // namespace CppEditor::Tests::Internal
+} // CppEditor::Tests::Internal
diff --git a/src/plugins/cppeditor/cppsourceprocessertesthelper.h b/src/plugins/cppeditor/cppsourceprocessertesthelper.h
index ba6428f77c..69f82156b6 100644
--- a/src/plugins/cppeditor/cppsourceprocessertesthelper.h
+++ b/src/plugins/cppeditor/cppsourceprocessertesthelper.h
@@ -6,6 +6,8 @@
 #include <QtGlobal>
 #include <QString>
 
+namespace Utils { class FilePath; }
+
 namespace CppEditor::Tests::Internal {
 
 class TestIncludePaths
@@ -17,7 +19,7 @@ public:
     static QString globalQtCoreIncludePath();
     static QString globalIncludePath();
     static QString directoryOfTestFile();
-    static QString testFilePath(const QString &fileName = QLatin1String("file.cpp"));
+    static Utils::FilePath testFilePath(const QString &fileName = QLatin1String("file.cpp"));
 };
 
-} // namespace CppEditor::Tests::Internal
+} // CppEditor::Tests::Internal
diff --git a/src/plugins/cppeditor/cppsourceprocessor.cpp b/src/plugins/cppeditor/cppsourceprocessor.cpp
index 1e11b8939c..2cd0eafae1 100644
--- a/src/plugins/cppeditor/cppsourceprocessor.cpp
+++ b/src/plugins/cppeditor/cppsourceprocessor.cpp
@@ -383,12 +383,12 @@ void CppSourceProcessor::mergeEnvironment(Document::Ptr doc)
 
     const QList<Document::Include> includes = doc->resolvedIncludes();
     for (const Document::Include &incl : includes) {
-        const QString includedFile = incl.resolvedFileName();
+        const FilePath includedFile = incl.resolvedFileName();
 
         if (Document::Ptr includedDoc = m_snapshot.document(includedFile))
             mergeEnvironment(includedDoc);
-        else if (!m_included.contains(FilePath::fromString(includedFile)))
-            run(includedFile);
+        else if (!m_included.contains(includedFile))
+            run(includedFile.toString());
     }
 
     m_env.addMacros(doc->definedMacros());
@@ -416,7 +416,7 @@ void CppSourceProcessor::sourceNeeded(int line, const QString &fileName, Include
     const FilePath absoluteFilePath = FilePath::fromString(absoluteFileName);
 
     if (m_currentDoc) {
-        m_currentDoc->addIncludeFile(Document::Include(fileName, absoluteFileName, line, type));
+        m_currentDoc->addIncludeFile(Document::Include(fileName, absoluteFilePath, line, type));
         if (absoluteFileName.isEmpty()) {
             m_currentDoc->addDiagnosticMessage(messageNoSuchFile(m_currentDoc, fileName, line));
             return;
@@ -453,7 +453,7 @@ void CppSourceProcessor::sourceNeeded(int line, const QString &fileName, Include
     document->setLanguageFeatures(m_languageFeatures);
     for (const QString &include : initialIncludes) {
         m_included.insert(FilePath::fromString(include));
-        Document::Include inc(include, include, 0, IncludeLocal);
+        Document::Include inc(include, FilePath::fromString(include), 0, IncludeLocal);
         document->addIncludeFile(inc);
     }
     if (info.exists())
diff --git a/src/plugins/cppeditor/cppsourceprocessor_test.cpp b/src/plugins/cppeditor/cppsourceprocessor_test.cpp
index 06b1748d8f..af617637f7 100644
--- a/src/plugins/cppeditor/cppsourceprocessor_test.cpp
+++ b/src/plugins/cppeditor/cppsourceprocessor_test.cpp
@@ -39,15 +39,15 @@ public:
         cleanUp();
     }
 
-    Document::Ptr run(const QString &filePath) const
+    Document::Ptr run(const FilePath &filePath) const
     {
         QScopedPointer<CppSourceProcessor> sourceProcessor(
                     CppModelManager::createSourceProcessor());
         sourceProcessor->setHeaderPaths({ProjectExplorer::HeaderPath::makeUser(
                                          TestIncludePaths::directoryOfTestFile())});
-        sourceProcessor->run(filePath);
+        sourceProcessor->run(filePath.toString());
 
-        Document::Ptr document = m_cmm->document(Utils::FilePath::fromString(filePath));
+        Document::Ptr document = m_cmm->document(filePath);
         return document;
     }
 
@@ -70,7 +70,7 @@ private:
 /// Check: Resolved and unresolved includes are properly tracked.
 void SourceProcessorTest::testIncludesResolvedUnresolved()
 {
-    const QString testFilePath
+    const FilePath testFilePath
             = TestIncludePaths::testFilePath(QLatin1String("test_main_resolvedUnresolved.cpp"));
 
     SourcePreprocessor processor;
@@ -81,7 +81,7 @@ void SourceProcessorTest::testIncludesResolvedUnresolved()
     QCOMPARE(resolvedIncludes.size(), 1);
     QCOMPARE(resolvedIncludes.at(0).type(), Client::IncludeLocal);
     QCOMPARE(resolvedIncludes.at(0).unresolvedFileName(), QLatin1String("header.h"));
-    const QString expectedResolvedFileName
+    const FilePath expectedResolvedFileName
             = TestIncludePaths::testFilePath(QLatin1String("header.h"));
     QCOMPARE(resolvedIncludes.at(0).resolvedFileName(), expectedResolvedFileName);
 
@@ -95,10 +95,9 @@ void SourceProcessorTest::testIncludesResolvedUnresolved()
 /// Check: Avoid self-include entries due to cyclic includes.
 void SourceProcessorTest::testIncludesCyclic()
 {
-    const QString fileName1 = TestIncludePaths::testFilePath(QLatin1String("cyclic1.h"));
-    const QString fileName2 = TestIncludePaths::testFilePath(QLatin1String("cyclic2.h"));
-    const QSet<FilePath> sourceFiles = {FilePath::fromString(fileName1),
-                                        FilePath::fromString(fileName2)};
+    const FilePath filePath1 = TestIncludePaths::testFilePath(QLatin1String("cyclic1.h"));
+    const FilePath filePath2 = TestIncludePaths::testFilePath(QLatin1String("cyclic2.h"));
+    const QSet<FilePath> sourceFiles = {filePath1, filePath2};
 
     // Create global snapshot (needed in BuiltinEditorDocumentParser)
     TestCase testCase;
@@ -106,7 +105,7 @@ void SourceProcessorTest::testIncludesCyclic()
 
     // Open editor
     TextEditor::BaseTextEditor *editor;
-    QVERIFY(testCase.openCppEditor(FilePath::fromString(fileName1), &editor));
+    QVERIFY(testCase.openCppEditor(filePath1, &editor));
     testCase.closeEditorAtEndOfTestCase(editor);
 
     // Check editor snapshot
@@ -118,24 +117,24 @@ void SourceProcessorTest::testIncludesCyclic()
     QCOMPARE(snapshot.size(), 3); // Configuration file included
 
     // Check includes
-    Document::Ptr doc1 = snapshot.document(fileName1);
+    Document::Ptr doc1 = snapshot.document(filePath1);
     QVERIFY(doc1);
-    Document::Ptr doc2 = snapshot.document(fileName2);
+    Document::Ptr doc2 = snapshot.document(filePath2);
     QVERIFY(doc2);
 
     QCOMPARE(doc1->unresolvedIncludes().size(), 0);
     QCOMPARE(doc1->resolvedIncludes().size(), 1);
-    QCOMPARE(doc1->resolvedIncludes().first().resolvedFileName(), fileName2);
+    QCOMPARE(doc1->resolvedIncludes().first().resolvedFileName(), filePath2);
 
     QCOMPARE(doc2->unresolvedIncludes().size(), 0);
     QCOMPARE(doc2->resolvedIncludes().size(), 1);
-    QCOMPARE(doc2->resolvedIncludes().first().resolvedFileName(), fileName1);
+    QCOMPARE(doc2->resolvedIncludes().first().resolvedFileName(), filePath1);
 }
 
 /// Check: All include errors are reported as diagnostic messages.
 void SourceProcessorTest::testIncludesAllDiagnostics()
 {
-    const QString testFilePath
+    const FilePath testFilePath
             = TestIncludePaths::testFilePath(QLatin1String("test_main_allDiagnostics.cpp"));
 
     SourcePreprocessor processor;
@@ -149,7 +148,7 @@ void SourceProcessorTest::testIncludesAllDiagnostics()
 
 void SourceProcessorTest::testMacroUses()
 {
-    const QString testFilePath
+    const FilePath testFilePath
             = TestIncludePaths::testFilePath(QLatin1String("test_main_macroUses.cpp"));
 
     SourcePreprocessor processor;
diff --git a/src/plugins/cppeditor/includeutils.cpp b/src/plugins/cppeditor/includeutils.cpp
index f79bb8db12..4f89b1a059 100644
--- a/src/plugins/cppeditor/includeutils.cpp
+++ b/src/plugins/cppeditor/includeutils.cpp
@@ -450,7 +450,7 @@ int IncludeGroup::lineForNewInclude(const QString &newIncludeFileName,
         return -1;
 
     if (isSorted()) {
-        const Include newInclude(newIncludeFileName, QString(), 0, newIncludeType);
+        const Include newInclude(newIncludeFileName, FilePath(), 0, newIncludeType);
         const QList<Include>::const_iterator it = std::lower_bound(m_includes.begin(),
             m_includes.end(), newInclude, includeFileNamelessThen);
         if (it == m_includes.end())
@@ -509,22 +509,22 @@ using Tests::Internal::TestIncludePaths;
 
 namespace Internal {
 
-static QList<Include> includesForSource(const QString &filePath)
+static QList<Include> includesForSource(const FilePath &filePath)
 {
     CppModelManager *cmm = CppModelManager::instance();
     cmm->GC();
     QScopedPointer<CppSourceProcessor> sourceProcessor(CppModelManager::createSourceProcessor());
     sourceProcessor->setHeaderPaths({ProjectExplorer::HeaderPath::makeUser(
                                      TestIncludePaths::globalIncludePath())});
-    sourceProcessor->run(filePath);
+    sourceProcessor->run(filePath.toString());
 
-    Document::Ptr document = cmm->document(FilePath::fromString(filePath));
+    Document::Ptr document = cmm->document(filePath);
     return document->resolvedIncludes();
 }
 
 void IncludeGroupsTest::testDetectIncludeGroupsByNewLines()
 {
-    const QString testFilePath = TestIncludePaths::testFilePath(
+    const FilePath testFilePath = TestIncludePaths::testFilePath(
                 QLatin1String("test_main_detectIncludeGroupsByNewLines.cpp"));
 
     QList<Include> includes = includesForSource(testFilePath);
@@ -566,7 +566,7 @@ void IncludeGroupsTest::testDetectIncludeGroupsByNewLines()
 
 void IncludeGroupsTest::testDetectIncludeGroupsByIncludeDir()
 {
-    const QString testFilePath = TestIncludePaths::testFilePath(
+    const FilePath testFilePath = TestIncludePaths::testFilePath(
                 QLatin1String("test_main_detectIncludeGroupsByIncludeDir.cpp"));
 
     QList<Include> includes = includesForSource(testFilePath);
@@ -590,7 +590,7 @@ void IncludeGroupsTest::testDetectIncludeGroupsByIncludeDir()
 
 void IncludeGroupsTest::testDetectIncludeGroupsByIncludeType()
 {
-    const QString testFilePath = TestIncludePaths::testFilePath(
+    const FilePath testFilePath = TestIncludePaths::testFilePath(
                 QLatin1String("test_main_detectIncludeGroupsByIncludeType.cpp"));
 
     QList<Include> includes = includesForSource(testFilePath);
diff --git a/src/plugins/designer/qtcreatorintegration.cpp b/src/plugins/designer/qtcreatorintegration.cpp
index b077453bf0..d20744d839 100644
--- a/src/plugins/designer/qtcreatorintegration.cpp
+++ b/src/plugins/designer/qtcreatorintegration.cpp
@@ -114,7 +114,7 @@ static QList<Document::Ptr> findDocumentsIncluding(const Snapshot &docTable,
                     docList.append(doc);
                 }
             } else {
-                if (include.resolvedFileName() == fileName)
+                if (include.resolvedFileName().path() == fileName)
                     docList.append(doc);
             }
         }
diff --git a/src/plugins/modeleditor/componentviewcontroller.cpp b/src/plugins/modeleditor/componentviewcontroller.cpp
index 7c0e11d40c..a50604a2fa 100644
--- a/src/plugins/modeleditor/componentviewcontroller.cpp
+++ b/src/plugins/modeleditor/componentviewcontroller.cpp
@@ -152,18 +152,18 @@ void UpdateIncludeDependenciesVisitor::visitMComponent(qmt::MComponent *componen
         if (document) {
             const QList<CPlusPlus::Document::Include> includes = document->resolvedIncludes();
             for (const CPlusPlus::Document::Include &include : includes) {
-                QString includeFilePath = include.resolvedFileName();
+                Utils::FilePath includeFilePath = include.resolvedFileName();
                 // replace proxy header with real one
                 CPlusPlus::Document::Ptr includeDocument = snapshot.document(includeFilePath);
                 if (includeDocument) {
                     QList<CPlusPlus::Document::Include> includes = includeDocument->resolvedIncludes();
                     if (includes.count() == 1 &&
-                            QFileInfo(includes.at(0).resolvedFileName()).fileName() == QFileInfo(includeFilePath).fileName())
+                            includes.at(0).resolvedFileName().fileName() == includeFilePath.fileName())
                     {
                         includeFilePath = includes.at(0).resolvedFileName();
                     }
                 }
-                qmt::MComponent *includeComponent = findComponentFromFilePath(includeFilePath);
+                qmt::MComponent *includeComponent = findComponentFromFilePath(includeFilePath.toString());
                 if (includeComponent && includeComponent != component) {
                     // add dependency between components
                     if (!m_modelUtilities->haveDependency(component, includeComponent)) {
diff --git a/src/plugins/modeleditor/pxnodeutilities.cpp b/src/plugins/modeleditor/pxnodeutilities.cpp
index 55775228d1..100f347061 100644
--- a/src/plugins/modeleditor/pxnodeutilities.cpp
+++ b/src/plugins/modeleditor/pxnodeutilities.cpp
@@ -224,7 +224,7 @@ bool PxNodeUtilities::isProxyHeader(const QString &file) const
         QList<CPlusPlus::Document::Include> includes = document->resolvedIncludes();
         if (includes.count() != 1)
             return false;
-        return QFileInfo(includes.at(0).resolvedFileName()).fileName() == QFileInfo(file).fileName();
+        return includes.at(0).resolvedFileName().fileName() == QFileInfo(file).fileName();
     }
     return false;
 }
diff --git a/tests/auto/cplusplus/checksymbols/tst_checksymbols.cpp b/tests/auto/cplusplus/checksymbols/tst_checksymbols.cpp
index 25ca5d663f..314b0570f1 100644
--- a/tests/auto/cplusplus/checksymbols/tst_checksymbols.cpp
+++ b/tests/auto/cplusplus/checksymbols/tst_checksymbols.cpp
@@ -1148,14 +1148,14 @@ void tst_CheckSymbols::test_checksymbols_infiniteLoop()
     const QString filePath1 = QDir::tempPath() + QLatin1String("/file1.h");
     Tests::TestCase::writeFile(FilePath::fromString(filePath1), source1);
 
-    const QString filePath2 = QDir::tempPath() + QLatin1String("/file2.h");
-    Tests::TestCase::writeFile(FilePath::fromString(filePath2), source2);
+    const FilePath filePath2 = FilePath::fromString(QDir::tempPath()) / "/file2.h";
+    Tests::TestCase::writeFile(filePath2, source2);
 
     const Document::Ptr document1 = TestCase::createDocument(filePath1, source1);
     document1->addIncludeFile(Document::Include("file2.h", filePath2, 1, Client::IncludeLocal));
     Snapshot snapshot;
     snapshot.insert(document1);
-    snapshot.insert(TestCase::createDocument(filePath2, source2));
+    snapshot.insert(TestCase::createDocument(filePath2.toString(), source2));
 
     TestCase::runCheckSymbols(document1, snapshot);
 }