Switch tag order from strings to floats, as The Spec preaches

The Spec wasn't entirely consistent on this until recently but floats actually are used in the wild, rather than strings.

1 files changed, 28 insertions, 10 deletions

diff --git a/lib/events/accountdataevents.h b/lib/events/accountdataevents.h
index 94fc510a..27f6c77c 100644
--- a/lib/events/accountdataevents.h
+++ b/lib/events/accountdataevents.h
@@ -31,22 +31,40 @@ namespace QMatrixClient
 
     struct TagRecord
     {
-        TagRecord (QString order = {}) : order(std::move(order)) { }
-        explicit TagRecord(const QJsonValue& jv)
-            : order(jv.toObject().value("order"_ls).toString())
-        { }
+        using order_type = Omittable<float>;
+
+        order_type order;
 
-        QString order;
+        TagRecord (order_type order = none) : order(order) { }
+        explicit TagRecord(const QJsonValue& jv)
+        {
+            // Parse a float both from JSON double and JSON string because
+            // libqmatrixclient previously used to use strings to store order.
+            const auto orderJv = jv.toObject().value("order"_ls);
+            if (orderJv.isDouble())
+                order = fromJson<float>(orderJv);
+            else if (orderJv.isString())
+            {
+                bool ok;
+                order = orderJv.toString().toFloat(&ok);
+                if (!ok)
+                    order = none;
+            }
+        }
 
-        bool operator==(const TagRecord& other) const
-            { return order == other.order; }
-        bool operator!=(const TagRecord& other) const
-            { return !operator==(other); }
+        bool operator<(const TagRecord& other) const
+        {
+            // Per The Spec, rooms with no order should be after those with order
+            return !order.omitted() &&
+                        (other.order.omitted() || order.value() < other.order.value());
+        }
     };
 
     inline QJsonValue toJson(const TagRecord& rec)
     {
-        return QJsonObject {{ QStringLiteral("order"), rec.order }};
+        QJsonObject o;
+        addParam(o, QStringLiteral("order"), rec.order);
+        return o;
     }
 
     using TagsMap = QHash<QString, TagRecord>;