ClangCodeModel: remove duplicates from clangd quickfix assist

Do not report quickfixes with a diagnostic since those are already
collected by the ClangdQuickFixFactory as builtin quickfixes.

Change-Id: I8d29a08b823291f8beaa762c09b7d29a4b9d0384
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>

src/plugins/clangcodemodel/clangdclient.cpp

@@ -1429,12 +1429,31 @@ private:
         return nullptr;
     }
 
-    void handleProposalReady(const QuickFixOperations &ops) override
+    TextEditor::GenericProposal *handleCodeActionResult(const CodeActionResult &result) override
     {
-        // Step 3: Merge the results upon callback from clangd.
-        for (const auto &op : ops)
+        auto toOperation =
+            [=](const Utils::variant<Command, CodeAction> &item) -> QuickFixOperation * {
+            if (auto action = Utils::get_if<CodeAction>(&item)) {
+                const Utils::optional<QList<Diagnostic>> diagnostics = action->diagnostics();
+                if (!diagnostics.has_value() || diagnostics->isEmpty())
+                    return new CodeActionQuickFixOperation(*action, client());
+            }
+            if (auto command = Utils::get_if<Command>(&item))
+                return new CommandQuickFixOperation(*command, client());
+            return nullptr;
+        };
+
+        if (auto list = Utils::get_if<QList<Utils::variant<Command, CodeAction>>>(&result)) {
+            QuickFixOperations ops;
+            for (const Utils::variant<Command, CodeAction> &item : *list) {
+                if (QuickFixOperation *op = toOperation(item)) {
                     op->setDescription("clangd: " + op->description());
-        setAsyncProposalAvailable(GenericProposal::createProposal(m_interface, ops + m_builtinOps));
+                    ops << op;
+                }
+            }
+            return GenericProposal::createProposal(m_interface, ops + m_builtinOps);
+        }
+        return nullptr;
     }
 
     QuickFixOperations m_builtinOps;

src/plugins/languageclient/languageclientquickfix.cpp

@@ -55,23 +55,17 @@ void CodeActionQuickFixOperation::perform()
         m_client->executeCommand(*command);
 }
 
-class CommandQuickFixOperation : public QuickFixOperation
-{
-public:
-    CommandQuickFixOperation(const Command &command, Client *client)
+CommandQuickFixOperation::CommandQuickFixOperation(const Command &command, Client *client)
     : m_command(command)
     , m_client(client)
-    { setDescription(command.title()); }
-    void perform() override
-    {
+{ setDescription(command.title()); }
+
+
+void CommandQuickFixOperation::perform()
+{
     if (m_client)
         m_client->executeCommand(m_command);
-    }
-
-private:
-    Command m_command;
-    QPointer<Client> m_client;
-};
+}
 
 IAssistProposal *LanguageClientQuickFixAssistProcessor::perform(const AssistInterface *interface)
 {
@@ -119,24 +113,26 @@ void LanguageClientQuickFixAssistProcessor::handleCodeActionResponse(const CodeA
     m_currentRequest.reset();
     if (const Utils::optional<CodeActionRequest::Response::Error> &error = response.error())
         m_client->log(*error);
+    m_client->removeAssistProcessor(this);
+    GenericProposal *proposal = nullptr;
+    if (const Utils::optional<CodeActionResult> &result = response.result())
+        proposal = handleCodeActionResult(*result);
+    setAsyncProposalAvailable(proposal);
+}
+
+GenericProposal *LanguageClientQuickFixAssistProcessor::handleCodeActionResult(const CodeActionResult &result)
+{
+    if (auto list = Utils::get_if<QList<Utils::variant<Command, CodeAction>>>(&result)) {
         QuickFixOperations ops;
-    if (const Utils::optional<CodeActionResult> &result = response.result()) {
-        if (auto list = Utils::get_if<QList<Utils::variant<Command, CodeAction>>>(&*result)) {
         for (const Utils::variant<Command, CodeAction> &item : *list) {
             if (auto action = Utils::get_if<CodeAction>(&item))
                 ops << new CodeActionQuickFixOperation(*action, m_client);
             else if (auto command = Utils::get_if<Command>(&item))
                 ops << new CommandQuickFixOperation(*command, m_client);
         }
+        return GenericProposal::createProposal(m_assistInterface.data(), ops);
     }
-    }
-    m_client->removeAssistProcessor(this);
-    handleProposalReady(ops);
-}
-
-void LanguageClientQuickFixAssistProcessor::handleProposalReady(const QuickFixOperations &ops)
-{
-    setAsyncProposalAvailable(GenericProposal::createProposal(m_assistInterface.data(), ops));
+    return nullptr;
 }
 
 LanguageClientQuickFixProvider::LanguageClientQuickFixProvider(Client *client)

src/plugins/languageclient/languageclientquickfix.h

@@ -35,7 +35,10 @@
 
 #include <QPointer>
 
-namespace TextEditor { class IAssistProposal; }
+namespace TextEditor {
+class IAssistProposal;
+class GenericProposal;
+} // namespace TextEditor
 
 namespace LanguageClient {
 
@@ -52,6 +55,17 @@ private:
     QPointer<Client> m_client;
 };
 
+class LANGUAGECLIENT_EXPORT CommandQuickFixOperation : public TextEditor::QuickFixOperation
+{
+public:
+    CommandQuickFixOperation(const LanguageServerProtocol::Command &command, Client *client);
+    void perform() override;
+
+private:
+    LanguageServerProtocol::Command m_command;
+    QPointer<Client> m_client;
+};
+
 class LANGUAGECLIENT_EXPORT LanguageClientQuickFixProvider : public TextEditor::IAssistProvider
 {
 public:
@@ -77,10 +91,13 @@ public:
 
 protected:
     void setOnlyKinds(const QList<LanguageServerProtocol::CodeActionKind> &only);
+    Client *client() { return m_client; }
 
 private:
-    void handleCodeActionResponse(const LanguageServerProtocol::CodeActionRequest::Response &response);
-    virtual void handleProposalReady(const TextEditor::QuickFixOperations &ops);
+    void handleCodeActionResponse(
+        const LanguageServerProtocol::CodeActionRequest::Response &response);
+    virtual TextEditor::GenericProposal *handleCodeActionResult(
+        const LanguageServerProtocol::CodeActionResult &result);
 
     QSharedPointer<const TextEditor::AssistInterface> m_assistInterface;
     Client *m_client = nullptr; // not owned