chore: address DCM lint warnings

Author: spydon

packages/postgrest/lib/src/postgrest_typed_builder.dart

@@ -26,7 +26,7 @@ void _toVoid(dynamic data) {}
 /// before it is returned, so awaiting it never exposes raw
 /// `Map<String, dynamic>` data.
 class PostgrestTypedBuilder<T> implements Future<T> {
-  PostgrestTypedBuilder._(this._rawBuilder, this._convert);
+  const PostgrestTypedBuilder._(this._rawBuilder, this._convert);
 
   final PostgrestBuilder<dynamic, dynamic, dynamic> _rawBuilder;
   final T Function(dynamic data) _convert;

packages/postgrest/lib/src/postgrest_typed_filter_builder.dart

@@ -6,7 +6,7 @@ part of 'postgrest_typed_builder.dart';
 /// checks the value type of each filter against its column at compile time.
 class PostgrestTypedFilterBuilder<Row, T>
     extends PostgrestTypedTransformBuilder<Row, T> {
-  PostgrestTypedFilterBuilder._(
+  const PostgrestTypedFilterBuilder._(
     PostgrestFilterBuilder<dynamic> super.rawBuilder,
     super.table,
     super.convert,

packages/postgrest/lib/src/postgrest_typed_query_builder.dart

@@ -9,7 +9,7 @@ part of 'postgrest_typed_builder.dart';
 /// {@endtemplate}
 class PostgrestTypedQueryBuilder<Row> {
   /// {@macro postgrest_typed_query_builder}
-  PostgrestTypedQueryBuilder(
+  const PostgrestTypedQueryBuilder(
     PostgrestQueryBuilder<dynamic> queryBuilder,
     this.table,
   ) : _queryBuilder = queryBuilder;

packages/postgrest/lib/src/postgrest_typed_transform_builder.dart

@@ -5,7 +5,7 @@ part of 'postgrest_typed_builder.dart';
 /// [Row] is the type a single row converts into and [T] is the type the
 /// request resolves to when awaited.
 class PostgrestTypedTransformBuilder<Row, T> extends PostgrestTypedBuilder<T> {
-  PostgrestTypedTransformBuilder._(
+  const PostgrestTypedTransformBuilder._(
     PostgrestTransformBuilder<dynamic> super.rawBuilder,
     this._table,
     super.convert,

packages/postgrest/test/typed_query_test.dart

@@ -4,11 +4,14 @@ import 'package:http/http.dart';
 import 'package:postgrest/postgrest.dart';
 import 'package:test/test.dart';
 
-extension type Book(Map<String, dynamic> json) {
-  int get id => json['id'] as int;
-  String get title => json['title'] as String;
+extension type const Book(Map<String, dynamic> _json)
+    implements Map<String, dynamic> {
+  int get id => _json['id'] as int;
+  String get title => _json['title'] as String;
 }
 
+const bookRows = '[{"id":1,"title":"a"},{"id":2,"title":"b"}]';
+
 class Books {
   static const table = PostgrestTable('books', Book.new);
   static const id = TableColumn<int>('id');
@@ -41,8 +44,6 @@ void main() {
   late MockHttpClient httpClient;
   late PostgrestClient client;
 
-  const bookRows = '[{"id":1,"title":"a"},{"id":2,"title":"b"}]';
-
   setUp(() {
     httpClient = MockHttpClient();
     client = PostgrestClient(
@@ -94,7 +95,7 @@ void main() {
           .where(Books.id.eq(1))
           .maybeSingle();
 
-      expect(book, isNull);
+      expect(book == null, isTrue);
     });
 
     test('maybeSingle returns the row when one matches', () async {

packages/supabase/lib/src/supabase_typed_query_builder.dart

@@ -10,7 +10,7 @@ class SupabaseTypedQueryBuilder<Row> extends PostgrestTypedQueryBuilder<Row> {
   // The query builder is also kept as a field to expose [stream], so it
   // cannot become a super parameter.
   // ignore: use_super_parameters
-  SupabaseTypedQueryBuilder(
+  const SupabaseTypedQueryBuilder(
     SupabaseQueryBuilder queryBuilder,
     PostgrestTable<Row> table,
   ) : _queryBuilder = queryBuilder,

packages/supabase/lib/src/supabase_typed_stream_builder.dart

@@ -5,8 +5,10 @@ import 'package:supabase/supabase.dart';
 /// The typed counterpart of [SupabaseStreamBuilder]; emits the rows of the
 /// table converted into [Row] through [PostgrestTable.rowFromJson].
 class SupabaseTypedStreamBuilder<Row> extends Stream<List<Row>> {
-  SupabaseTypedStreamBuilder(SupabaseStreamBuilder streamBuilder, this._table)
-    : _streamBuilder = streamBuilder;
+  const SupabaseTypedStreamBuilder(
+    SupabaseStreamBuilder streamBuilder,
+    this._table,
+  ) : _streamBuilder = streamBuilder;
 
   final SupabaseStreamBuilder _streamBuilder;
   final PostgrestTable<Row> _table;
@@ -59,7 +61,7 @@ class SupabaseTypedStreamBuilder<Row> extends Stream<List<Row>> {
 /// A [SupabaseTypedStreamBuilder] that can still be filtered with [filter].
 class SupabaseTypedStreamFilterBuilder<Row>
     extends SupabaseTypedStreamBuilder<Row> {
-  SupabaseTypedStreamFilterBuilder(
+  const SupabaseTypedStreamFilterBuilder(
     SupabaseStreamFilterBuilder super.streamBuilder,
     super.table,
   );

packages/supabase/test/mock_test.dart

@@ -7,10 +7,11 @@ import 'dart:io';
 import 'package:supabase/supabase.dart';
 import 'package:test/test.dart';
 
-extension type Todo(Map<String, dynamic> json) {
-  int get id => json['id'] as int;
-  String get task => json['task'] as String;
-  bool get status => json['status'] as bool;
+extension type const Todo(Map<String, dynamic> _json)
+    implements Map<String, dynamic> {
+  int get id => _json['id'] as int;
+  String get task => _json['task'] as String;
+  bool get status => _json['status'] as bool;
 }
 
 class Todos {