Cancel streamed download cancellation for Http2Adapter

dio/test/cancel_token_test.dart

@@ -45,6 +45,8 @@ void main() {
           cancelToken.cancel();
         });
 
+        expect(response.statusCode, 200);
+
         await expectLater(
           (response.data as ResponseBody).stream.last,
           throwsA(predicate((DioException e) =>

plugins/http2_adapter/CHANGELOG.md

@@ -4,6 +4,7 @@
 
 - Implement `sendTimeout` and `receiveTimeout` for the adapter.
 - Fix redirect not working when requestStream is null.
+- Fix cancellation for streamed responses and downloads.
 
 ## 2.3.1+1
 

plugins/http2_adapter/lib/src/http2_adapter.dart

@@ -74,13 +74,6 @@ class Http2Adapter implements HttpClientAdapter {
     // Creates a new outgoing stream.
     final stream = transport.makeRequest(headers);
 
-    // ignore: unawaited_futures
-    cancelFuture?.whenComplete(() {
-      Future(() {
-        stream.terminate();
-      });
-    });
-
     List<Uint8List>? list;
     final hasRequestData = requestStream != null;
     if (!excludeMethods.contains(options.method) && hasRequestData) {
@@ -110,6 +103,7 @@ class Http2Adapter implements HttpClientAdapter {
     await stream.outgoingMessages.close();
 
     final sc = StreamController<Uint8List>();
+
     final responseHeaders = Headers();
     final completer = Completer();
     late int statusCode;
@@ -158,6 +152,14 @@ class Http2Adapter implements HttpClientAdapter {
       cancelOnError: true,
     );
 
+    /// Cancel any up/download streams if the [CancelToken] is cancelled
+    /// and propagate the [DioException] to the response stream.
+    cancelFuture?.whenComplete(() {
+      stream.terminate();
+      sc.addError(options.cancelToken!.cancelError!);
+      subscription.cancel();
+    });
+
     final receiveTimeout = options.receiveTimeout;
     if (receiveTimeout != null) {
       await completer.future.timeout(

plugins/http2_adapter/pubspec.yaml

@@ -22,3 +22,4 @@ dev_dependencies:
   crypto: ^3.0.2
   lints: any
   test: ^1.16.4
+  path: ^1.8.0

plugins/http2_adapter/test/request_test.dart

@@ -0,0 +1,94 @@
+@TestOn('vm')
+import 'dart:io';
+
+import 'package:dio/dio.dart';
+import 'package:dio_http2_adapter/dio_http2_adapter.dart';
+import 'package:path/path.dart' as p;
+import 'package:test/test.dart';
+
+void main() {
+  late Directory tmp;
+
+  final dio = Dio()
+    ..httpClientAdapter = Http2Adapter(null)
+    ..options.baseUrl = 'https://httpbun.com/';
+
+  setUpAll(() {
+    tmp = Directory.systemTemp.createTempSync('dio_http_download_test');
+    addTearDown(() {
+      tmp.deleteSync(recursive: true);
+    });
+  });
+
+  group('requests', () {
+    test('download README.md', () async {
+      final path = p.join(tmp.path, 'README.md');
+
+      int count = 0;
+      int total = 0;
+      final source = File('README.md');
+      await dio.download(
+        '/payload',
+        path,
+        options: Options(
+          method: 'POST',
+          contentType: 'text/plain',
+        ),
+        data: source.openRead(),
+        onReceiveProgress: (c, t) {
+          total = t;
+          count = c;
+        },
+      );
+
+      final f = File(path);
+      expect(f.readAsStringSync(), source.readAsStringSync());
+      expect(count, await source.length());
+
+      // TODO: disabled pending https://github.com/sharat87/httpbun/issues/13
+      // expect(count, total);
+    });
+
+    test('cancels request', () async {
+      final cancelToken = CancelToken();
+
+      expectLater(
+        dio.get(
+          'get',
+          cancelToken: cancelToken,
+        ),
+        throwsA(predicate((DioException e) =>
+            e.type == DioExceptionType.cancel &&
+            e.message!
+                .contains('The request was manually cancelled by the user'))),
+      );
+
+      Future.delayed(const Duration(milliseconds: 50), () {
+        cancelToken.cancel();
+      });
+    });
+
+    test('cancels streamed responses', () async {
+      final cancelToken = CancelToken();
+      final response = await dio.get(
+        'bytes/${1024 * 1024 * 10}',
+        options: Options(responseType: ResponseType.stream),
+        cancelToken: cancelToken,
+      );
+
+      Future.delayed(const Duration(milliseconds: 750), () {
+        cancelToken.cancel();
+      });
+
+      expect(response.statusCode, 200);
+
+      await expectLater(
+        (response.data as ResponseBody).stream.last,
+        throwsA(predicate((DioException e) =>
+            e.type == DioExceptionType.cancel &&
+            e.message!
+                .contains('The request was manually cancelled by the user'))),
+      );
+    });
+  });
+}