Debugger: Move struct sorting logic to generic parser

Backends only have to specify whether an object members are sortable
in principle (e.g. all structs), and some numeric 'sortgroup' value
for member items (higher values are always sorted on top).

Change-Id: I10ce94580374fed48a35f058a575a1408d6801af
Reviewed-by: David Schulz <david.schulz@theqtcompany.com>
Reviewed-by: Christian Stenger <christian.stenger@theqtcompany.com>

src/plugins/debugger/watchdata.cpp

@@ -118,6 +118,7 @@ WatchItem::WatchItem() :
     bitsize(0),
     elided(0),
     arrayIndex(-1),
+    sortGroup(0),
     wantsChildren(false),
     valueEnabled(true),
     valueEditable(true),
@@ -380,7 +381,18 @@ static void decodeArrayData(WatchItem *item, const QByteArray &rawData,
     qDebug() << "ENCODING ERROR: " << encoding.toString();
 }
 
-void WatchItem::parseHelper(const GdbMi &input)
+static bool sortByName(const Utils::TreeItem *a, const Utils::TreeItem *b)
+{
+    auto aa = static_cast<const WatchItem *>(a);
+    auto bb = static_cast<const WatchItem *>(b);
+
+    if (aa->sortGroup != bb->sortGroup)
+        return aa->sortGroup > bb->sortGroup;
+
+    return aa->name < bb->name;
+}
+
+void WatchItem::parseHelper(const GdbMi &input, bool maySort)
 {
     setChildrenUnneeded();
 
@@ -437,6 +449,10 @@ void WatchItem::parseHelper(const GdbMi &input)
     if (mi.isValid())
         exp = mi.data();
 
+    mi = input["sortgroup"];
+    if (mi.isValid())
+        sortGroup = mi.toInt();
+
     mi = input["valueenabled"];
     if (mi.data() == "true")
         valueEnabled = true;
@@ -500,14 +516,17 @@ void WatchItem::parseHelper(const GdbMi &input)
                 QByteArray key = subinput["key"].data();
                 if (!key.isEmpty())
                     child->name = decodeData(key, subinput["keyencoded"].data());
-                child->parseHelper(subinput);
+                child->parseHelper(subinput, maySort);
                 appendChild(child);
             }
+
+            if (maySort && input["sortable"].toInt())
+                sortChildren(&sortByName);
         }
     }
 }
 
-void WatchItem::parse(const GdbMi &data)
+void WatchItem::parse(const GdbMi &data, bool maySort)
 {
     iname = data["iname"].data();
 
@@ -517,7 +536,7 @@ void WatchItem::parse(const GdbMi &data)
     else
         name = QString::fromLatin1(data["name"].data());
 
-    parseHelper(data);
+    parseHelper(data, maySort);
 
     if (wname.isValid())
         exp = name.toUtf8();