Merge remote-tracking branch 'origin/11.0'

Conflicts:
	src/plugins/debugger/debuggeritemmanager.cpp

Change-Id: I9d99d13feff9315f52eacbd84857c63cb69bf804

src/plugins/clangcodemodel/clangdclient.cpp

@@ -978,6 +978,12 @@ MessageId ClangdClient::requestSymbolInfo(const Utils::FilePath &filePath, const
     return symReq.id();
 }
 
+#ifdef WITH_TESTS
+ClangdFollowSymbol *ClangdClient::currentFollowSymbolOperation()
+{
+    return d->followSymbol;
+}
+#endif
 
 void ClangdClient::followSymbol(TextDocument *document,
         const QTextCursor &cursor,
@@ -990,8 +996,8 @@ void ClangdClient::followSymbol(TextDocument *document,
 {
     QTC_ASSERT(documentOpen(document), openDocument(document));
 
-    delete d->followSymbol;
-    d->followSymbol = nullptr;
+    if (d->followSymbol)
+        d->followSymbol->cancel();
 
     const QTextCursor adjustedCursor = d->adjustedCursor(cursor, document);
     if (followTo == FollowTo::SymbolDef && !resolveTarget) {
@@ -1001,12 +1007,14 @@ void ClangdClient::followSymbol(TextDocument *document,
 
     qCDebug(clangdLog) << "follow symbol requested" << document->filePath()
                        << adjustedCursor.blockNumber() << adjustedCursor.positionInBlock();
-    d->followSymbol = new ClangdFollowSymbol(this, adjustedCursor, editorWidget, document, callback,
-                                             followTo, openInSplit);
-    connect(d->followSymbol, &ClangdFollowSymbol::done, this, [this] {
-        d->followSymbol->deleteLater();
-        d->followSymbol = nullptr;
+    auto clangdFollowSymbol = new ClangdFollowSymbol(this, adjustedCursor, editorWidget, document,
+                                                     callback, followTo, openInSplit);
+    connect(clangdFollowSymbol, &ClangdFollowSymbol::done, this, [this, clangdFollowSymbol] {
+        clangdFollowSymbol->deleteLater();
+        if (clangdFollowSymbol == d->followSymbol)
+            d->followSymbol = nullptr;
     });
+    d->followSymbol = clangdFollowSymbol;
 }
 
 void ClangdClient::switchDeclDef(TextDocument *document, const QTextCursor &cursor,

src/plugins/clangcodemodel/clangdclient.h

@@ -37,6 +37,8 @@ void setupClangdConfigFile();
 
 enum class FollowTo { SymbolDef, SymbolType };
 
+class ClangdFollowSymbol;
+
 class ClangdClient : public LanguageClient::Client
 {
     Q_OBJECT
@@ -117,6 +119,10 @@ public:
             const LanguageServerProtocol::Position &position,
             const SymbolInfoHandler &handler);
 
+#ifdef WITH_TESTS
+    ClangdFollowSymbol *currentFollowSymbolOperation();
+#endif
+
 signals:
     void indexingFinished();
     void foundReferences(const Utils::SearchResultItems &items);

src/plugins/clangcodemodel/clangdfollowsymbol.cpp

@@ -90,6 +90,7 @@ public:
     void closeTempDocuments();
     bool addOpenFile(const FilePath &filePath);
     bool defLinkIsAmbiguous() const;
+    void cancel();
 
     ClangdFollowSymbol * const q;
     ClangdClient * const client;
@@ -169,18 +170,17 @@ ClangdFollowSymbol::ClangdFollowSymbol(ClangdClient *client, const QTextCursor &
 
 ClangdFollowSymbol::~ClangdFollowSymbol()
 {
-    d->closeTempDocuments();
-    if (d->virtualFuncAssistProcessor)
-        d->virtualFuncAssistProcessor->resetData(false);
-    for (const MessageId &id : std::as_const(d->pendingSymbolInfoRequests))
-        d->client->cancelRequest(id);
-    for (const MessageId &id : std::as_const(d->pendingGotoImplRequests))
-        d->client->cancelRequest(id);
-    for (const MessageId &id : std::as_const(d->pendingGotoDefRequests))
-        d->client->cancelRequest(id);
+    d->cancel();
     delete d;
 }
 
+void ClangdFollowSymbol::cancel()
+{
+    d->cancel();
+    clear();
+    emitDone();
+}
+
 void ClangdFollowSymbol::clear()
 {
     d->openedFiles.clear();
@@ -221,6 +221,19 @@ bool ClangdFollowSymbol::Private::defLinkIsAmbiguous() const
     return true;
 }
 
+void ClangdFollowSymbol::Private::cancel()
+{
+    closeTempDocuments();
+    if (virtualFuncAssistProcessor)
+        virtualFuncAssistProcessor->resetData(false);
+    for (const MessageId &id : std::as_const(pendingSymbolInfoRequests))
+        client->cancelRequest(id);
+    for (const MessageId &id : std::as_const(pendingGotoImplRequests))
+        client->cancelRequest(id);
+    for (const MessageId &id : std::as_const(pendingGotoDefRequests))
+        client->cancelRequest(id);
+}
+
 bool ClangdFollowSymbol::Private::addOpenFile(const FilePath &filePath)
 {
     return openedFiles.insert(filePath).second;

src/plugins/clangcodemodel/clangdfollowsymbol.h

@@ -28,6 +28,7 @@ public:
                        TextEditor::TextDocument *document, const Utils::LinkHandler &callback,
                        FollowTo followTo, bool openInSplit);
     ~ClangdFollowSymbol();
+    void cancel();
     void clear();
 
 signals:

src/plugins/clangcodemodel/test/clangdtests.cpp

@@ -4,6 +4,7 @@
 #include "clangdtests.h"
 
 #include "../clangdclient.h"
+#include "../clangdfollowsymbol.h"
 #include "../clangmodelmanagersupport.h"
 
 #include <coreplugin/editormanager/editormanager.h>
@@ -428,6 +429,37 @@ void ClangdTestFollowSymbol::test()
     QCOMPARE(actualLink.targetColumn + 1, targetColumn);
 }
 
+// Make sure it is safe to call follow symbol in a follow symbol handler. Since follow symbol
+// potentially opens a file that gets loaded in chunks which handles user events inbetween
+// the chunks we can potentially call a follow symbol while currently handling another one.
+void ClangdTestFollowSymbol::testFollowSymbolInHandler()
+{
+    TextEditor::TextDocument *const doc = document("header.h");
+    QVERIFY(doc);
+    QTimer timer;
+    timer.setSingleShot(true);
+    QEventLoop loop;
+    QTextCursor cursor(doc->document());
+    const int pos = Text::positionInText(doc->document(), 48, 9);
+    cursor.setPosition(pos);
+    QObject::connect(&timer, &QTimer::timeout, &loop, &QEventLoop::quit);
+
+    bool deleted = false;
+
+    const auto handler = [&](const Link &) {
+        client()->followSymbol(doc, cursor, nullptr, [&](const Link &) { loop.quit(); }, true,
+                               FollowTo::SymbolDef, false);
+        QVERIFY(!deleted);
+    };
+
+    client()->followSymbol(doc, cursor, nullptr, handler, true, FollowTo::SymbolDef, false);
+    QVERIFY(client()->currentFollowSymbolOperation());
+    connect(client()->currentFollowSymbolOperation(), &QObject::destroyed, [&] { deleted = true; });
+    timer.start(10000);
+    loop.exec();
+    QVERIFY(timer.isActive());
+    timer.stop();
+}
 
 ClangdTestLocalReferences::ClangdTestLocalReferences()
 {

src/plugins/clangcodemodel/test/clangdtests.h

@@ -86,6 +86,7 @@ public:
 private slots:
     void test_data();
     void test();
+    void testFollowSymbolInHandler();
 };
 
 class ClangdTestLocalReferences : public ClangdTest