ClangCodeModel: Special rendering for deprecated completion items

We add the attribute textually and show a warning icon.

Fixes: QTCREATORBUG-2325
Change-Id: Icc0305a703e26c84095167087b30fa3456f97614
Reviewed-by: David Schulz <david.schulz@qt.io>

src/libs/languageserverprotocol/completion.cpp

@@ -49,6 +49,16 @@ Utils::optional<CompletionItem::InsertTextFormat> CompletionItem::insertTextForm
     return Utils::nullopt;
 }
 
+Utils::optional<QList<CompletionItem::CompletionItemTag>> CompletionItem::tags() const
+{
+    if (const auto value = optionalValue<QJsonArray>(tagsKey)) {
+        QList<CompletionItemTag> tags;
+        for (auto it = value->cbegin(); it != value->cend(); ++it)
+            tags << static_cast<CompletionItemTag>(it->toInt());
+        return tags;
+    }
+    return {};
+}
 
 CompletionItemResolveRequest::CompletionItemResolveRequest(const CompletionItem &params)
     : Request(methodName, params)

src/libs/languageserverprotocol/completion.h

@@ -214,6 +214,27 @@ public:
     void setData(const QJsonValue &data) { insert(dataKey, data); }
     void clearData() { remove(dataKey); }
 
+    /**
+     * Completion item tags are extra annotations that tweak the rendering of a
+     * completion item.
+     * @since 3.15.0
+     */
+    enum CompletionItemTag {
+        Deprecated = 1,
+    };
+
+    /**
+     * Tags for this completion item.
+     * @since 3.15.0
+     */
+    Utils::optional<QList<CompletionItemTag>> tags() const;
+
+    /**
+      * Indicates if this item is deprecated.
+      * @deprecated Use `tags` instead if supported.
+      */
+    Utils::optional<bool> deprecated() const { return optionalValue<bool>(deprecatedKey); }
+
     bool isValid() const override { return contains(labelKey); }
 };
 

src/libs/languageserverprotocol/jsonkeys.h

@@ -209,6 +209,7 @@ constexpr char symbolKindKey[] = "symbolKind";
 constexpr char syncKindKey[] = "syncKind";
 constexpr char synchronizationKey[] = "synchronization";
 constexpr char tabSizeKey[] = "tabSize";
+constexpr char tagsKey[] = "tags";
 constexpr char targetKey[] = "target";
 constexpr char textDocumentKey[] = "textDocument";
 constexpr char textDocumentSyncKey[] = "textDocumentSync";

src/plugins/clangcodemodel/clangdclient.cpp

@@ -741,6 +741,7 @@ public:
 
 private:
     QIcon icon() const override;
+    QString text() const override;
 };
 
 class ClangdClient::ClangdCompletionAssistProcessor : public LanguageClientCompletionAssistProcessor
@@ -2551,6 +2552,8 @@ ClangdCompletionItem::SpecialQtType ClangdCompletionItem::getQtType(const Comple
 
 QIcon ClangdCompletionItem::icon() const
 {
+    if (isDeprecated())
+        return Utils::Icons::WARNING.icon();
     const SpecialQtType qtType = getQtType(item());
     switch (qtType) {
     case SpecialQtType::Signal:
@@ -2566,6 +2569,14 @@ QIcon ClangdCompletionItem::icon() const
     return LanguageClientCompletionItem::icon();
 }
 
+QString ClangdCompletionItem::text() const
+{
+    const QString clangdValue = LanguageClientCompletionItem::text();
+    if (isDeprecated())
+        return "[[deprecated]]" + clangdValue;
+    return clangdValue;
+}
+
 MessageId ClangdClient::Private::getAndHandleAst(const TextDocOrFile &doc,
                                                  const AstHandler &astHandler,
                                                  AstCallbackMode callbackMode, const Range &range)

src/plugins/languageclient/languageclientcompletionassist.cpp

@@ -227,6 +227,15 @@ bool LanguageClientCompletionItem::isPerfectMatch(int pos, QTextDocument *doc) c
     return textToInsert == textAt(QTextCursor(doc), pos - length, length);
 }
 
+bool LanguageClientCompletionItem::isDeprecated() const
+{
+    if (const auto tags = m_item.tags(); tags && tags->contains(CompletionItem::Deprecated))
+        return true;
+    if (const auto deprecated = m_item.deprecated())
+        return *deprecated;
+    return false;
+}
+
 class LanguageClientCompletionModel : public GenericProposalModel
 {
 public:

src/plugins/languageclient/languageclientcompletionassist.h

@@ -135,6 +135,7 @@ public:
     bool operator <(const LanguageClientCompletionItem &other) const;
 
     bool isPerfectMatch(int pos, QTextDocument *doc) const;
+    bool isDeprecated() const;
 
 private:
     LanguageServerProtocol::CompletionItem m_item;