feat: move hasMulticastAddress extension to core package

Author: JKRhb

lib/core.dart

@@ -9,8 +9,10 @@
 /// runtime used for consuming, exposing, and discovering Things.
 library core;
 
+// TODO(JKRhb): Reorganize top-level core package into smaller packages.
 export "src/core/definitions.dart";
 export "src/core/exceptions.dart";
+export "src/core/extensions.dart";
 export "src/core/implementation.dart";
 export "src/core/protocol_interfaces.dart";
 export "src/core/scripting_api.dart";

lib/src/binding_coap/coap_client.dart

@@ -506,7 +506,7 @@ final class CoapClient extends ProtocolClient {
     final streamController = StreamController<DiscoveryContent>();
 
     // TODO: Replace once https://github.com/shamblett/coap/pull/129 is merged
-    if (uri.isMulticastAddress) {
+    if (uri.hasMulticastAddress) {
       multicastResponseHandler = coap.CoapMulticastResponseHandler(
         (data) {
           streamController.add(data.determineDiscoveryContent(uri.scheme));
@@ -526,7 +526,7 @@ final class CoapClient extends ProtocolClient {
       multicastResponseHandler: multicastResponseHandler,
     );
 
-    if (uri.isMulticastAddress) {
+    if (uri.hasMulticastAddress) {
       yield* streamController.stream;
     } else {
       yield content;

lib/src/binding_coap/coap_extensions.dart

@@ -4,7 +4,6 @@
 //
 // SPDX-License-Identifier: BSD-3-Clause
 
-import "dart:io";
 import "dart:typed_data";
 
 import "package:cbor/cbor.dart";
@@ -16,15 +15,6 @@ import "../../core.dart" hide PskCredentials;
 import "coap_binding_exception.dart";
 import "coap_definitions.dart";
 
-/// Extension which makes it easier to handle [Uri]s containing
-/// [InternetAddress]es.
-extension InternetAddressMethods on Uri {
-  /// Checks whether the host of this [Uri] is a multicast [InternetAddress].
-  bool get isMulticastAddress {
-    return InternetAddress.tryParse(host)?.isMulticast ?? false;
-  }
-}
-
 /// CoAP-specific extensions for the [AugmentedForm] class.
 extension CoapFormExtension on AugmentedForm {
   T? _obtainVocabularyTerm<T>(String vocabularyTerm) {

lib/src/core/extensions.dart

@@ -0,0 +1,10 @@
+// Copyright 2024 Contributors to the Eclipse Foundation. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+/// Sub-library for extensions used by `dart_wot`.
+library extensions;
+
+export "extensions/uri_extensions.dart";

lib/src/core/extensions/uri_extensions.dart

@@ -0,0 +1,16 @@
+// Copyright 2024 Contributors to the Eclipse Foundation. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+import "dart:io";
+
+/// Extension that makes it easier to handle [Uri]s which potentially contain
+/// [InternetAddress]es.
+extension InternetAddressMethodExtension on Uri {
+  /// Checks whether the host of this [Uri] is a multicast [InternetAddress].
+  bool get hasMulticastAddress {
+    return InternetAddress.tryParse(host)?.isMulticast ?? false;
+  }
+}