LSP: add support for hierarchical document symbols

The result of the document symbol request was a flat list of symbols
until version 3.10.0 of the Protocol. The new result type also added
whether a symbol is deprecated and what text should get selected
when a symbol is activated in the IDE UI.

Change-Id: Id30366c44198434c240f3a21b8b237bf6819a425
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/libs/languageserverprotocol/jsonkeys.h

@@ -43,6 +43,7 @@ constexpr char changeKey[] = "change";
 constexpr char changeNotificationsKey[] = "changeNotifications";
 constexpr char changesKey[] = "changes";
 constexpr char characterKey[] = "character";
+constexpr char childrenKey[] = "children";
 constexpr char codeActionKey[] = "codeAction";
 constexpr char codeActionProviderKey[] = "codeActionProvider";
 constexpr char codeKey[] = "code";
@@ -73,6 +74,7 @@ constexpr char dataKey[] = "data";
 constexpr char defaultCharset[] = "utf-8";
 constexpr char definitionKey[] = "definition";
 constexpr char definitionProviderKey[] = "definitionProvider";
+constexpr char deprecatedKey[] = "deprecated";
 constexpr char detailKey[] = "detail";
 constexpr char diagnosticsKey[] = "diagnostics";
 constexpr char didChangeConfigurationKey[] = "didChangeConfiguration";
@@ -160,6 +162,7 @@ constexpr char saveKey[] = "save";
 constexpr char schemeKey[] = "scheme";
 constexpr char scopeUriKey[] = "scopeUri";
 constexpr char sectionKey[] = "section";
+constexpr char selectionRangeKey[] = "selectionRange";
 constexpr char settingsKey[] = "settings";
 constexpr char severityKey[] = "severity";
 constexpr char signatureHelpKey[] = "signatureHelp";

src/libs/languageserverprotocol/languagefeatures.cpp

@@ -277,15 +277,30 @@ GotoResult::GotoResult(const QJsonValue &value)
     }
 }
 
+template<typename Symbol>
+QList<Symbol> documentSymbolsResultArray(const QJsonArray &array)
+{
+    QList<Symbol> ret;
+    for (auto arrayValue : array) {
+        if (arrayValue.isObject())
+            ret << Symbol(arrayValue.toObject());
+    }
+    return ret;
+}
+
 DocumentSymbolsResult::DocumentSymbolsResult(const QJsonValue &value)
 {
     if (value.isArray()) {
-        QList<SymbolInformation> symbols;
+        QJsonArray array = value.toArray();
-        for (auto arrayValue : value.toArray()) {
+        if (array.isEmpty()) {
-            if (arrayValue.isObject())
+            *this = QList<SymbolInformation>();
-                symbols.append(SymbolInformation(arrayValue.toObject()));
+        } else {
+            QJsonObject arrayObject = array.first().toObject();
+            if (arrayObject.contains(rangeKey))
+                *this = documentSymbolsResultArray<DocumentSymbol>(array);
+            else
+                *this = documentSymbolsResultArray<SymbolInformation>(array);
         }
-        *this = symbols;
     } else {
         *this = nullptr;
     }

src/libs/languageserverprotocol/languagefeatures.h

@@ -323,7 +323,7 @@ public:
 using DocumentSymbolParams = TextDocumentParams;
 
 class LANGUAGESERVERPROTOCOL_EXPORT DocumentSymbolsResult
-        : public Utils::variant<QList<SymbolInformation>, std::nullptr_t>
+        : public Utils::variant<QList<SymbolInformation>, QList<DocumentSymbol>, std::nullptr_t>
 {
 public:
     using variant::variant;

src/libs/languageserverprotocol/lsptypes.h

@@ -430,6 +430,10 @@ public:
     int kind() const { return typedValue<int>(kindKey); }
     void setKind(int kind) { insert(kindKey, kind); }
 
+    Utils::optional<bool> deprecated() const { return optionalValue<bool>(deprecatedKey); }
+    void setDeprecated(bool deprecated) { insert(deprecatedKey, deprecated); }
+    void clearDeprecated() { remove(deprecatedKey); }
+
     Location location() const { return typedValue<Location>(locationKey); }
     void setLocation(const Location &location) { insert(locationKey, location); }
 
@@ -441,6 +445,37 @@ public:
     bool isValid(QStringList *error) const override;
 };
 
+class LANGUAGESERVERPROTOCOL_EXPORT DocumentSymbol : public JsonObject
+{
+public:
+    using JsonObject::JsonObject;
+
+    QString name() const { return typedValue<QString>(nameKey); }
+    void setName(const QString &name) { insert(nameKey, name); }
+
+    Utils::optional<QString> detail() const { return optionalValue<QString>(detailKey); }
+    void setDetail(const QString &detail) { insert(detailKey, detail); }
+    void clearDetail() { remove(detailKey); }
+
+    int kind() const { return typedValue<int>(kindKey); }
+    void setKind(int kind) { insert(kindKey, kind); }
+
+    Utils::optional<bool> deprecated() const { return optionalValue<bool>(deprecatedKey); }
+    void setDeprecated(bool deprecated) { insert(deprecatedKey, deprecated); }
+    void clearDeprecated() { remove(deprecatedKey); }
+
+    Range range() const { return typedValue<Range>(rangeKey); }
+    void setRange(Range range) { insert(rangeKey, range); }
+
+    Range selectionRange() const { return typedValue<Range>(selectionRangeKey); }
+    void setSelectionRange(Range selectionRange) { insert(selectionRangeKey, selectionRange); }
+
+    Utils::optional<QList<DocumentSymbol>> children() const
+    { return optionalArray<DocumentSymbol>(childrenKey); }
+    void setChildren(QList<DocumentSymbol> children) { insertArray(childrenKey, children); }
+    void clearChildren() { remove(childrenKey); }
+};
+
 enum class SymbolKind {
     File = 1,
     FirstSymbolKind = File,