Support assigning nested collections via templated API (#7478)

Co-authored-by: Thomas Goyne <[email protected]>

Author: jedelbo

CHANGELOG.md

@@ -92,6 +92,7 @@
 
 ### Enhancements
 * Introduce sync 'progress_estimate' parameter (value from 0.0 to 1.0) for existing sync 'ProgressNotifierCallback' api to report sync progress on current batch of upload/download until completion ([#7450](https://github.com/realm/realm-core/issues/7450))
+* Support assigning nested collections via templated API (PR [#7478](https://github.com/realm/realm-core/pull/7478))
 
 ### Fixed
 * Fix an assertion failure "m_lock_info && m_lock_info->m_file.get_path() == m_filename" that appears to be related to opening a Realm while the file is in the process of being closed on another thread ([Swift #8507](https://github.com/realm/realm-swift/issues/8507)).

src/realm/collection.cpp

@@ -243,10 +243,6 @@ UpdateStatus CollectionBase::do_init_from_parent(BPlusTreeBase* tree, ref_type r
         tree->init_from_ref(ref);
     }
     else {
-        if (tree->init_from_parent()) {
-            // All is well
-            return UpdateStatus::Updated;
-        }
         if (!allow_create) {
             tree->detach();
             return UpdateStatus::Detached;

src/realm/list.hpp

@@ -260,7 +260,7 @@ class Lst final : public CollectionBaseImpl<LstBase> {
             m_tree->set_parent(const_cast<ArrayParent*>(parent), 0);
         }
         Base::update_content_version();
-        return do_init_from_parent(m_tree.get(), 0, allow_create);
+        return do_init_from_parent(m_tree.get(), Base::get_collection_ref(), allow_create);
     }
 
     template <class Func>

src/realm/object-store/dictionary.hpp

@@ -142,7 +142,6 @@ class Dictionary : public object_store::Collection {
     Obj get_object(StringData key) const;
 };
 
-
 template <typename Fn>
 auto Dictionary::dispatch(Fn&& fn) const
 {
@@ -178,62 +177,7 @@ inline Obj Dictionary::get<Obj>(StringData key) const
     return get_object(key);
 }
 
-template <typename T, typename Context>
-void Dictionary::insert(Context& ctx, StringData key, T&& value, CreatePolicy policy)
-{
-    if (ctx.is_null(value)) {
-        this->insert(key, Mixed());
-        return;
-    }
-    if (m_is_embedded) {
-        validate_embedded(ctx, value, policy);
-        auto obj_key = dict().create_and_insert_linked_object(key).get_key();
-        ctx.template unbox<Obj>(value, policy, obj_key);
-        return;
-    }
-    dispatch([&](auto t) {
-        this->insert(key, ctx.template unbox<std::decay_t<decltype(*t)>>(value, policy));
-    });
-}
-
-template <typename Context>
-auto Dictionary::get(Context& ctx, StringData key) const
-{
-    return dispatch([&](auto t) {
-        return ctx.box(this->get<std::decay_t<decltype(*t)>>(key));
-    });
-}
-
-template <typename T, typename Context>
-void Dictionary::assign(Context& ctx, T&& values, CreatePolicy policy)
-{
-    if (ctx.is_same_dictionary(*this, values))
-        return;
-
-    if (ctx.is_null(values)) {
-        remove_all();
-        return;
-    }
-
-    if (!policy.diff)
-        remove_all();
-
-    ctx.enumerate_dictionary(values, [&](StringData key, auto&& value) {
-        if (policy.diff) {
-            util::Optional<Mixed> old_value = dict().try_get(key);
-            auto new_value = ctx.template unbox<Mixed>(value);
-            if (!old_value || *old_value != new_value) {
-                dict().insert(key, new_value);
-            }
-        }
-        else {
-            this->insert(ctx, key, value, policy);
-        }
-    });
-}
-
 } // namespace object_store
 } // namespace realm
 
-
 #endif /* REALM_OS_DICTIONARY_HPP */

src/realm/object-store/impl/object_accessor_impl.hpp

@@ -31,6 +31,11 @@ namespace realm {
 using AnyDict = std::map<std::string, std::any>;
 using AnyVector = std::vector<std::any>;
 
+struct UnmanagedObject {
+    std::string object_type;
+    std::any properties;
+};
+
 // An object accessor context which can be used to create and access objects
 // using std::any as the type-erased value type. In addition, this serves as
 // the reference implementation of an accessor context that must be implemented
@@ -370,7 +375,7 @@ inline util::Optional<UUID> CppContext::unbox(std::any& v, CreatePolicy, ObjKey)
 }
 
 template <>
-inline Mixed CppContext::unbox(std::any& v, CreatePolicy, ObjKey) const
+inline Mixed CppContext::unbox(std::any& v, CreatePolicy policy, ObjKey) const
 {
     if (v.has_value()) {
         const std::type_info& this_type{v.type()};
@@ -408,6 +413,23 @@ inline Mixed CppContext::unbox(std::any& v, CreatePolicy, ObjKey) const
         else if (this_type == typeid(UUID)) {
             return Mixed(util::any_cast<UUID>(v));
         }
+        else if (this_type == typeid(AnyDict)) {
+            return Mixed(0, CollectionType::Dictionary);
+        }
+        else if (this_type == typeid(AnyVector)) {
+            return Mixed(0, CollectionType::List);
+        }
+        else if (this_type == typeid(UnmanagedObject)) {
+            UnmanagedObject unmanaged_obj = util::any_cast<UnmanagedObject>(v);
+            auto os = realm->schema().find(unmanaged_obj.object_type);
+            CppContext child_ctx(realm, &*os);
+            auto obj = child_ctx.unbox<Obj>(unmanaged_obj.properties, policy, ObjKey());
+            return Mixed(obj);
+        }
+        else if (this_type == typeid(Obj)) {
+            Obj obj = util::any_cast<Obj>(v);
+            return Mixed(obj);
+        }
     }
     return Mixed{};
 }

src/realm/object-store/list.hpp

@@ -127,9 +127,6 @@ class List : public object_store::Collection {
     template <typename T>
     auto& as() const;
 
-    template <typename T, typename Context>
-    void set_if_different(Context&, size_t row_ndx, T&& value, CreatePolicy);
-
     friend struct std::hash<List>;
 };
 
@@ -164,120 +161,6 @@ auto List::dispatch(Fn&& fn) const
     return switch_on_type(get_type(), std::forward<Fn>(fn));
 }
 
-template <typename Context>
-auto List::get(Context& ctx, size_t row_ndx) const
-{
-    return dispatch([&](auto t) {
-        return ctx.box(this->get<std::decay_t<decltype(*t)>>(row_ndx));
-    });
-}
-
-template <typename T, typename Context>
-size_t List::find(Context& ctx, T&& value) const
-{
-    return dispatch([&](auto t) {
-        return this->find(ctx.template unbox<std::decay_t<decltype(*t)>>(value, CreatePolicy::Skip));
-    });
-}
-
-template <typename T, typename Context>
-void List::add(Context& ctx, T&& value, CreatePolicy policy)
-{
-    if (m_is_embedded) {
-        validate_embedded(ctx, value, policy);
-        auto key = as<Obj>().create_and_insert_linked_object(size()).get_key();
-        ctx.template unbox<Obj>(value, policy, key);
-        return;
-    }
-    dispatch([&](auto t) {
-        this->add(ctx.template unbox<std::decay_t<decltype(*t)>>(value, policy));
-    });
-}
-
-template <typename T, typename Context>
-void List::insert(Context& ctx, size_t list_ndx, T&& value, CreatePolicy policy)
-{
-    if (m_is_embedded) {
-        validate_embedded(ctx, value, policy);
-        auto key = as<Obj>().create_and_insert_linked_object(list_ndx).get_key();
-        ctx.template unbox<Obj>(value, policy, key);
-        return;
-    }
-    dispatch([&](auto t) {
-        this->insert(list_ndx, ctx.template unbox<std::decay_t<decltype(*t)>>(value, policy));
-    });
-}
-
-template <typename T, typename Context>
-void List::set(Context& ctx, size_t list_ndx, T&& value, CreatePolicy policy)
-{
-    if (m_is_embedded) {
-        validate_embedded(ctx, value, policy);
-
-        auto& list = as<Obj>();
-        auto key = policy.diff ? list.get(list_ndx) : list.create_and_set_linked_object(list_ndx).get_key();
-        ctx.template unbox<Obj>(value, policy, key);
-        return;
-    }
-    dispatch([&](auto t) {
-        this->set(list_ndx, ctx.template unbox<std::decay_t<decltype(*t)>>(value, policy));
-    });
-}
-
-template <typename T, typename Context>
-void List::set_if_different(Context& ctx, size_t row_ndx, T&& value, CreatePolicy policy)
-{
-    if (m_is_embedded) {
-        validate_embedded(ctx, value, policy);
-        auto key = policy.diff ? this->get<Obj>(row_ndx) : as<Obj>().create_and_set_linked_object(row_ndx);
-        ctx.template unbox<Obj>(value, policy, key.get_key());
-        return;
-    }
-    dispatch([&](auto t) {
-        using U = std::decay_t<decltype(*t)>;
-        if constexpr (std::is_same_v<U, Obj>) {
-            auto old_value = this->get<U>(row_ndx);
-            auto new_value = ctx.template unbox<U>(value, policy, old_value.get_key());
-            if (new_value.get_key() != old_value.get_key())
-                this->set(row_ndx, new_value);
-        }
-        else {
-            auto old_value = this->get<U>(row_ndx);
-            auto new_value = ctx.template unbox<U>(value, policy);
-            if (old_value != new_value)
-                this->set(row_ndx, new_value);
-        }
-    });
-}
-
-template <typename T, typename Context>
-void List::assign(Context& ctx, T&& values, CreatePolicy policy)
-{
-    if (ctx.is_same_list(*this, values))
-        return;
-
-    if (ctx.is_null(values)) {
-        remove_all();
-        return;
-    }
-
-    if (!policy.diff)
-        remove_all();
-
-    size_t sz = size();
-    size_t index = 0;
-    ctx.enumerate_collection(values, [&](auto&& element) {
-        if (index >= sz)
-            this->add(ctx, element, policy);
-        else if (policy.diff)
-            this->set_if_different(ctx, index, element, policy);
-        else
-            this->set(ctx, index, element, policy);
-        index++;
-    });
-    while (index < sz)
-        remove(--sz);
-}
 } // namespace realm
 
 namespace std {