blob: 114f5ee831fdb4447b90beb595e90704da2f79e2 [file] [log] [blame]
// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import 'dart:async';
import 'package:flutter/foundation.dart';
import 'package:flutter/services.dart';
import 'package:flutter_test/flutter_test.dart';
export 'package:flutter/services.dart' show TextEditingValue, TextInputAction;
/// A testing stub for the system's onscreen keyboard.
///
/// Typical app tests will not need to use this class directly.
///
/// The [TestWidgetsFlutterBinding] class registers a [TestTextInput] instance
/// ([TestWidgetsFlutterBinding.testTextInput]) as a stub keyboard
/// implementation if its [TestWidgetsFlutterBinding.registerTestTextInput]
/// property returns true when a test starts, and unregisters it when the test
/// ends (unless it ends with a failure).
///
/// See [register], [unregister], and [isRegistered] for details.
///
/// The [enterText], [updateEditingValue], [receiveAction], and
/// [closeConnection] methods can be used even when the [TestTextInput] is not
/// registered. All other methods will assert if [isRegistered] is false.
///
/// See also:
///
/// * [WidgetTester.enterText], which uses this class to simulate keyboard input.
/// * [WidgetTester.showKeyboard], which uses this class to simulate showing the
/// popup keyboard and initializing its text.
class TestTextInput {
/// Create a fake keyboard backend.
///
/// The [onCleared] argument may be set to be notified of when the keyboard
/// is dismissed.
TestTextInput({ this.onCleared });
/// Called when the keyboard goes away.
///
/// To use the methods on this API that send fake keyboard messages (such as
/// [updateEditingValue], [enterText], or [receiveAction]), the keyboard must
/// first be requested, e.g. using [WidgetTester.showKeyboard].
final VoidCallback? onCleared;
/// Log for method calls.
///
/// For all registered channels, handled calls are added to the list. Can
/// be cleaned using `log.clear()`.
final List<MethodCall> log = <MethodCall>[];
/// Installs this object as a mock handler for [SystemChannels.textInput].
///
/// Called by the binding at the top of a test when
/// [TestWidgetsFlutterBinding.registerTestTextInput] is true.
void register() => SystemChannels.textInput.setMockMethodCallHandler(_handleTextInputCall);
/// Removes this object as a mock handler for [SystemChannels.textInput].
///
/// After calling this method, the channel will exchange messages with the
/// Flutter engine instead of the stub.
///
/// Called by the binding at the end of a (successful) test when
/// [TestWidgetsFlutterBinding.registerTestTextInput] is true.
void unregister() => SystemChannels.textInput.setMockMethodCallHandler(null);
/// Whether this [TestTextInput] is registered with [SystemChannels.textInput].
///
/// The binding uses the [register] and [unregister] methods to control this
/// value when [TestWidgetsFlutterBinding.registerTestTextInput] is true.
bool get isRegistered => SystemChannels.textInput.checkMockMethodCallHandler(_handleTextInputCall);
int? _client;
/// Whether there are any active clients listening to text input.
bool get hasAnyClients {
assert(isRegistered);
return _client != null && _client! > 0;
}
/// The last set of arguments supplied to the `TextInput.setClient` and
/// `TextInput.updateConfig` methods of this stub implementation.
Map<String, dynamic>? setClientArgs;
/// The last set of arguments that [TextInputConnection.setEditingState] sent
/// to this stub implementation (i.e. the arguments set to
/// `TextInput.setEditingState`).
///
/// This is a map representation of a [TextEditingValue] object. For example,
/// it will have a `text` entry whose value matches the most recent
/// [TextEditingValue.text] that was sent to the embedder.
Map<String, dynamic>? editingState;
/// Whether the onscreen keyboard is visible to the user.
///
/// Specifically, this reflects the last call to `TextInput.show` or
/// `TextInput.hide` received by the stub implementation.
bool get isVisible {
assert(isRegistered);
return _isVisible;
}
bool _isVisible = false;
/// Resets any internal state of this object.
///
/// This method is invoked by the testing framework between tests. It should
/// not ordinarily be called by tests directly.
void reset() {
log.clear();
_client = null;
setClientArgs = null;
editingState = null;
_isVisible = false;
}
Future<dynamic> _handleTextInputCall(MethodCall methodCall) async {
log.add(methodCall);
switch (methodCall.method) {
case 'TextInput.setClient':
final List<dynamic> arguments = methodCall.arguments as List<dynamic>;
_client = arguments[0] as int;
setClientArgs = arguments[1] as Map<String, dynamic>;
break;
case 'TextInput.updateConfig':
setClientArgs = methodCall.arguments as Map<String, dynamic>;
break;
case 'TextInput.clearClient':
_client = null;
_isVisible = false;
onCleared?.call();
break;
case 'TextInput.setEditingState':
editingState = methodCall.arguments as Map<String, dynamic>;
break;
case 'TextInput.show':
_isVisible = true;
break;
case 'TextInput.hide':
_isVisible = false;
break;
}
}
/// Simulates the user hiding the onscreen keyboard.
///
/// This does nothing but set the internal flag.
void hide() {
assert(isRegistered);
_isVisible = false;
}
/// Simulates the user changing the text of the focused text field, and resets
/// the selection.
///
/// Calling this method replaces the content of the connected input field with
/// `text`, and places the caret at the end of the text.
///
/// To update the UI under test after this method is invoked, use
/// [WidgetTester.pump].
///
/// This can be called even if the [TestTextInput] has not been [register]ed.
///
/// If this is used to inject text when there is a real IME connection, for
/// example when using the [integration_test] library, there is a risk that
/// the real IME will become confused as to the current state of input.
///
/// See also:
///
/// * [updateEditingValue], which takes a [TextEditingValue] so that one can
/// also change the selection.
void enterText(String text) {
updateEditingValue(TextEditingValue(
text: text,
selection: TextSelection.collapsed(offset: text.length),
));
}
/// Simulates the user changing the [TextEditingValue] to the given value.
///
/// To update the UI under test after this method is invoked, use
/// [WidgetTester.pump].
///
/// This can be called even if the [TestTextInput] has not been [register]ed.
///
/// If this is used to inject text when there is a real IME connection, for
/// example when using the [integration_test] library, there is a risk that
/// the real IME will become confused as to the current state of input.
///
/// See also:
///
/// * [enterText], which is similar but takes only a String and resets the
/// selection.
void updateEditingValue(TextEditingValue value) {
TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
SystemChannels.textInput.name,
SystemChannels.textInput.codec.encodeMethodCall(
MethodCall(
'TextInputClient.updateEditingState',
<dynamic>[_client ?? -1, value.toJSON()],
),
),
(ByteData? data) { /* ignored */ },
);
}
/// Simulates the user pressing one of the [TextInputAction] buttons.
/// Does not check that the [TextInputAction] performed is an acceptable one
/// based on the `inputAction` [setClientArgs].
///
/// This can be called even if the [TestTextInput] has not been [register]ed.
///
/// If this is used to inject an action when there is a real IME connection,
/// for example when using the [integration_test] library, there is a risk
/// that the real IME will become confused as to the current state of input.
Future<void> receiveAction(TextInputAction action) async {
return TestAsyncUtils.guard(() {
final Completer<void> completer = Completer<void>();
TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
SystemChannels.textInput.name,
SystemChannels.textInput.codec.encodeMethodCall(
MethodCall(
'TextInputClient.performAction',
<dynamic>[_client ?? -1, action.toString()],
),
),
(ByteData? data) {
assert(data != null);
try {
// Decoding throws a PlatformException if the data represents an
// error, and that's all we care about here.
SystemChannels.textInput.codec.decodeEnvelope(data!);
// If we reach here then no error was found. Complete without issue.
completer.complete();
} catch (error) {
// An exception occurred as a result of receiveAction()'ing. Report
// that error.
completer.completeError(error);
}
},
);
return completer.future;
});
}
/// Simulates the user closing the text input connection.
///
/// For example:
///
/// * User pressed the home button and sent the application to background.
/// * User closed the virtual keyboard.
///
/// This can be called even if the [TestTextInput] has not been [register]ed.
///
/// If this is used to inject text when there is a real IME connection, for
/// example when using the [integration_test] library, there is a risk that
/// the real IME will become confused as to the current state of input.
void closeConnection() {
TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
SystemChannels.textInput.name,
SystemChannels.textInput.codec.encodeMethodCall(
MethodCall(
'TextInputClient.onConnectionClosed',
<dynamic>[_client ?? -1],
),
),
(ByteData? data) { /* response from framework is discarded */ },
);
}
}