Rename `nullsOrder` to `nulls`, move sql strings to enums, add `nulls` argument to the factory methods

drift/lib/src/runtime/query_builder/components/order_by.dart

@@ -3,30 +3,28 @@ part of '../query_builder.dart';
 /// Describes how to order rows
 enum OrderingMode {
   /// Ascending ordering mode (lowest items first)
-  asc,
+  asc._('ASC'),
 
   /// Descending ordering mode (highest items first)
-  desc
-}
+  desc._('DESC');
 
-const _modeToString = {
-  OrderingMode.asc: 'ASC',
-  OrderingMode.desc: 'DESC',
-};
+  final String _mode;
+
+  const OrderingMode._(this._mode);
+}
 
 /// Describes how to order nulls
 enum NullsOrder {
   /// Place NULLs at the start
-  first,
+  first._('NULLS FIRST'),
 
   /// Place NULLs at the end
-  last,
-}
+  last._('NULLS LAST');
 
-const _nullsOrderToString = {
-  NullsOrder.first: 'NULLS FIRST',
-  NullsOrder.last: 'NULLS LAST',
-};
+  final String _order;
+
+  const NullsOrder._(this._order);
+}
 
 /// A single term in a [OrderBy] clause. The priority of this term is determined
 /// by its position in [OrderBy.terms].
@@ -38,29 +36,39 @@ class OrderingTerm extends Component {
   final OrderingMode mode;
 
   /// How to order NULLs.
-  /// When [nullsOrder] is [null], then it's ignored.
+  /// When [nulls] is [null], then it's ignored.
   ///
   /// Note that this feature are only available in sqlite3 version `3.30.0` and
   /// newer. When using `sqlite3_flutter_libs` or a web database, this is not
   /// a problem.
-  final NullsOrder? nullsOrder;
+  final NullsOrder? nulls;
 
-  /// Creates an ordering term by the [expression] and the [mode] (defaults to
-  /// ascending).
+  /// Creates an ordering term by the [expression], the [mode] (defaults to
+  /// ascending) and the [nulls].
   OrderingTerm({
     required this.expression,
     this.mode = OrderingMode.asc,
-    this.nullsOrder,
+    this.nulls,
   });
 
-  /// Creates an ordering term that sorts for ascending values of [expression].
-  factory OrderingTerm.asc(Expression expression) {
-    return OrderingTerm(expression: expression, mode: OrderingMode.asc);
+  /// Creates an ordering term that sorts for ascending values
+  /// of [expression] and the [nulls].
+  factory OrderingTerm.asc(Expression expression, [NullsOrder? nulls]) {
+    return OrderingTerm(
+      expression: expression,
+      mode: OrderingMode.asc,
+      nulls: nulls,
+    );
   }
 
-  /// Creates an ordering term that sorts for descending values of [expression].
-  factory OrderingTerm.desc(Expression expression) {
-    return OrderingTerm(expression: expression, mode: OrderingMode.desc);
+  /// Creates an ordering term that sorts for descending values
+  /// of [expression] and the [nulls].
+  factory OrderingTerm.desc(Expression expression, [NullsOrder? nulls]) {
+    return OrderingTerm(
+      expression: expression,
+      mode: OrderingMode.desc,
+      nulls: nulls,
+    );
   }
 
   /// Creates an ordering term  to get a number of random rows
@@ -73,10 +81,10 @@ class OrderingTerm extends Component {
   void writeInto(GenerationContext context) {
     expression.writeInto(context);
     context.writeWhitespace();
-    context.buffer.write(_modeToString[mode]);
-    if (nullsOrder != null) {
+    context.buffer.write(mode._mode);
+    if (nulls != null) {
       context.writeWhitespace();
-      context.buffer.write(_nullsOrderToString[nullsOrder]);
+      context.buffer.write(nulls?._order);
     }
   }
 }

drift/test/database/statements/order_by_test.dart

@@ -29,7 +29,7 @@ void main() {
     query.orderBy([
       (tbl) => OrderingTerm(
             expression: tbl.name,
-            nullsOrder: NullsOrder.last,
+            nulls: NullsOrder.last,
           ),
     ]);
     await query.get();
@@ -44,7 +44,7 @@ void main() {
     query.orderBy([
       (tbl) => OrderingTerm(
             expression: tbl.name,
-            nullsOrder: NullsOrder.first,
+            nulls: NullsOrder.first,
           ),
     ]);
     await query.get();
@@ -59,14 +59,14 @@ void main() {
     query.orderBy([
       (tbl) => OrderingTerm(
             expression: tbl.name,
-            nullsOrder: NullsOrder.first,
+            nulls: NullsOrder.first,
           ),
       (tbl) => OrderingTerm(
             expression: tbl.creationTime,
           ),
       (tbl) => OrderingTerm(
             expression: tbl.profilePicture,
-            nullsOrder: NullsOrder.last,
+            nulls: NullsOrder.last,
           ),
     ]);
     await query.get();