fake_api: Add apiException parameter; switch to it where needed

Author: gnprice

test/api/fake_api.dart

@@ -4,6 +4,7 @@ import 'dart:convert';
 import 'package:flutter/foundation.dart';
 import 'package:http/http.dart' as http;
 import 'package:zulip/api/core.dart';
+import 'package:zulip/api/exception.dart';
 import 'package:zulip/model/store.dart';
 
 import '../example_data.dart' as eg;
@@ -211,27 +212,47 @@ class FakeApiConnection extends ApiConnection {
 
   /// Prepare the HTTP response for the next request.
   ///
-  /// If `httpException` is null, the next request will produce an [http.Response]
+  /// If `httpException` and `apiException` are both null, then
+  /// the next request will produce an [http.Response]
   /// with the given `httpStatus`, defaulting to 200.  The body of the response
   /// will be `body` if non-null, or `jsonEncode(json)` if `json` is non-null,
   /// or else ''.  The `body` and `json` parameters must not both be non-null.
   ///
-  /// If `httpException` is non-null, then
+  /// If `httpException` is non-null, then `apiException`,
   /// `httpStatus`, `body`, and `json` must all be null, and the next request
   /// will throw the given exception within the HTTP client layer,
   /// causing the API request to throw a [NetworkException]
   /// wrapping the given exception.
   ///
-  /// In either case, the next request will complete a duration of `delay`
+  /// If `apiException` is non-null, then `httpException`,
+  /// `httpStatus`, `body`, and `json` must all be null, and the next request
+  /// will throw an exception equivalent to the given exception
+  /// (except [ApiRequestException.routeName], which is ignored).
+  ///
+  /// In each case, the next request will complete a duration of `delay`
   /// after being started.
   void prepare({
     Object? httpException,
+    ZulipApiException? apiException,
     int? httpStatus,
     Map<String, dynamic>? json,
     String? body,
     Duration delay = Duration.zero,
   }) {
     assert(isOpen);
+
+    if (apiException != null) {
+      assert(httpException == null
+        && httpStatus == null && json == null && body == null);
+      httpStatus = apiException.httpStatus;
+      json = {
+        'result': 'error',
+        'code': apiException.code,
+        'msg': apiException.message,
+        ...apiException.data,
+      };
+    }
+
     client.prepare(
       exception: httpException,
       httpStatus: httpStatus, json: json, body: body,

test/api/fake_api_test.dart

@@ -34,6 +34,22 @@ void main() {
         ..cause.identicalTo(exception));
   });
 
+  test('prepare API exception', () async {
+    final connection = FakeApiConnection();
+    final exception = ZulipApiException(routeName: 'someRoute',
+      httpStatus: 456, code: 'SOME_ERROR',
+      data: {'foo': ['bar']}, message: 'Something failed');
+    connection.prepare(apiException: exception);
+    await check(connection.get('aRoute', (json) => json, '/', null))
+      .throws((it) => it.isA<ZulipApiException>()
+        ..routeName.equals('aRoute') // actual route, not the prepared one
+        ..routeName.not((it) => it.equals(exception.routeName))
+        ..httpStatus.equals(exception.httpStatus)
+        ..code.equals(exception.code)
+        ..data.deepEquals(exception.data)
+        ..message.equals(exception.message));
+  });
+
   test('delay success', () => awaitFakeAsync((async) async {
     final connection = FakeApiConnection();
     connection.prepare(delay: const Duration(seconds: 2),

test/model/actions_test.dart

@@ -103,7 +103,7 @@ void main() {
       assert(unregisterDelay > TestGlobalStore.removeAccountDuration);
       final exception = eg.apiExceptionUnauthorized(routeName: 'removeEtcEtcToken');
       final newConnection = separateConnection()
-        ..prepare(delay: unregisterDelay, httpException: exception); // TODO this isn't an HTTP exception
+        ..prepare(delay: unregisterDelay, apiException: exception);
 
       final future = logOutAccount(testBinding.globalStore, eg.selfAccount.id);
       // Unregister-token request and account removal dispatched together
@@ -165,7 +165,7 @@ void main() {
 
       final exception = eg.apiExceptionUnauthorized(routeName: 'removeEtcEtcToken');
       final newConnection = separateConnection()
-        ..prepare(httpException: exception); // TODO this isn't an HTTP exception
+        ..prepare(apiException: exception);
       final future = unregisterToken(testBinding.globalStore, eg.selfAccount.id);
       async.elapse(Duration.zero);
       await future;