Support for conditionless queries

example/flutter/objectbox_demo/lib/main.dart

@@ -59,12 +59,8 @@ class ViewModel {
     _box = Box<Note>(_store);
 
     final dateProp = Note_.date;
-    final dummyCondition = dateProp.greaterThan(0);
 
-    _query = _box
-        .query(dummyCondition)
-        .order(dateProp, flags: Order.descending)
-        .build();
+    _query = _box.emptyQuery.order(dateProp, flags: Order.descending).build();
   }
 
   void addNote(Note note) => _box.put(note);

lib/src/bindings/signatures.dart

@@ -259,3 +259,10 @@ typedef obx_bytes_array_set_t<Ret, SizeT> = Ret Function(
     SizeT index,
     Pointer<Uint8> data,
     SizeT size);
+
+/*  // TODO
+    obx_qb_bytes_eq_dart_t obx_qb_bytes_equal;
+    obx_qb_bytes_lt_gt_dart_t obx_qb_bytes_greater, obx_qb_bytes_less;
+
+    obx_qb_param_alias_dart_t obx_qb_param_alias;
+*/

lib/src/box.dart

@@ -257,6 +257,10 @@ class Box<T> {
     }
   }
 
+  /// When no conditions are required on properties
+  QueryBuilder get emptyQuery =>
+      QueryBuilder<T>(_store, _fbManager, _modelEntity.id.id);
+
   /// Returns true if no objects are in this box.
   bool isEmpty() {
     final isEmpty = allocate<Uint8>();

lib/src/query/builder.dart

@@ -8,8 +8,8 @@ class QueryBuilder<T> {
   Pointer<Void> _cBuilder;
   final OBXFlatbuffersManager _fbManager;
 
-  QueryBuilder(
-      this._store, this._fbManager, this._entityId, this._queryCondition);
+  QueryBuilder(this._store, this._fbManager, this._entityId,
+      [this._queryCondition]);
 
   void _throwExceptionIfNecessary() {
     if (bindings.obx_qb_error_code(_cBuilder) != OBXError.OBX_SUCCESS) {
@@ -24,7 +24,7 @@ class QueryBuilder<T> {
   Query build() {
     _createBuilder();
 
-    if (0 == _queryCondition.apply(this, true)) {
+    if (_queryCondition != null && 0 == _queryCondition.apply(this, true)) {
       _throwExceptionIfNecessary();
     }
 
@@ -45,37 +45,3 @@ class QueryBuilder<T> {
     return this;
   }
 }
-
-/*  // Not done yet
-    obx_qb_bytes_eq_dart_t obx_qb_bytes_equal;
-    obx_qb_bytes_lt_gt_dart_t obx_qb_bytes_greater, obx_qb_bytes_less;
-
-    obx_qb_param_alias_dart_t obx_qb_param_alias;
-*/
-
-//////
-//////
-
-/** Inspiration
-    Modifier and Type	Method	Description
-    <TARGET> QueryBuilder<TARGET>	backlink​(RelationInfo<TARGET,?> relationInfo)
-    Creates a backlink (reversed link) to another entity, for which you also can describe conditions using the returned builder.
-    void	close()
- ** QueryBuilder<T>	eager​(int limit, RelationInfo relationInfo, RelationInfo... more)
-    Like eager(RelationInfo, RelationInfo[]), but limits eager loading to the given count.
- ** QueryBuilder<T>	eager​(RelationInfo relationInfo, RelationInfo... more)
-    Specifies relations that should be resolved eagerly.
- ** QueryBuilder<T>	filter​(QueryFilter<T> filter) // dart has built-in higher order functions
-    Sets a filter that executes on primary query results (returned from the db core) on a Java level.
-    <TARGET> QueryBuilder<TARGET>	link​(RelationInfo<?,TARGET> relationInfo)
-    Creates a link to another entity, for which you also can describe conditions using the returned builder.
- ** QueryBuilder<T>	order​(Property<T> property)
-    Specifies given property to be used for sorting.
- ** QueryBuilder<T>	order​(Property<T> property, int flags)
-    Defines the order with which the results are ordered (default: none).
- ** QueryBuilder<T>	orderDesc​(Property<T> property)
-    Specifies given property in descending order to be used for sorting.
- ** QueryBuilder<T>	parameterAlias​(java.lang.String alias)
-    Assigns the given alias to the previous condition.
- ** QueryBuilder<T>	sort​(java.util.Comparator<T> comparator)
- */

test/query_test.dart

@@ -15,6 +15,23 @@ void main() {
     box = env.box;
   });
 
+  test('Query with no conditions, and order as desc ints', () {
+    box.putMany([
+      TestEntity(tInt: 0),
+      TestEntity(tInt: 10),
+      TestEntity(tInt: 100),
+      TestEntity(tInt: 10),
+      TestEntity(tInt: 0),
+    ]);
+
+    var query =
+        box.emptyQuery.order(TestEntity_.tInt, flags: Order.descending).build();
+    final listDesc = query.find();
+    query.close();
+
+    expect(listDesc.map((t) => t.tInt).toList(), [100, 10, 10, 0, 0]);
+  });
+
   test('ignore transient field', () {
     box.put(TestEntity(tDouble: 0.1, ignore: 1337));