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// 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 'dart:ui' show SemanticsUpdate;
import 'package:flutter/foundation.dart';
import 'package:flutter/gestures.dart';
import 'package:flutter/rendering.dart';
import 'package:flutter/scheduler.dart';
import 'package:flutter/services.dart';
import 'package:flutter_test/flutter_test.dart' show EnginePhase, TestDefaultBinaryMessengerBinding, fail;
export 'package:flutter/foundation.dart' show FlutterError, FlutterErrorDetails;
export 'package:flutter_test/flutter_test.dart' show EnginePhase, TestDefaultBinaryMessengerBinding;
class TestRenderingFlutterBinding extends BindingBase with SchedulerBinding, ServicesBinding, GestureBinding, PaintingBinding, SemanticsBinding, RendererBinding, TestDefaultBinaryMessengerBinding {
/// Creates a binding for testing rendering library functionality.
///
/// If [onErrors] is not null, it is called if [FlutterError] caught any errors
/// while drawing the frame. If [onErrors] is null and [FlutterError] caught at least
/// one error, this function fails the test. A test may override [onErrors] and
/// inspect errors using [takeFlutterErrorDetails].
///
/// Errors caught between frames will cause the test to fail unless
/// [FlutterError.onError] has been overridden.
TestRenderingFlutterBinding({ this.onErrors }) {
FlutterError.onError = (FlutterErrorDetails details) {
FlutterError.dumpErrorToConsole(details);
Zone.current.parent!.handleUncaughtError(details.exception, details.stack!);
};
}
/// The current [TestRenderingFlutterBinding], if one has been created.
///
/// Provides access to the features exposed by this binding. The binding must
/// be initialized before using this getter; this is typically done by calling
/// [TestRenderingFlutterBinding.ensureInitialized].
static TestRenderingFlutterBinding get instance => BindingBase.checkInstance(_instance);
static TestRenderingFlutterBinding? _instance;
@override
void initInstances() {
super.initInstances();
_instance = this;
// TODO(goderbauer): Create (fake) window if embedder doesn't provide an implicit view.
assert(platformDispatcher.implicitView != null);
_renderView = initRenderView(platformDispatcher.implicitView!);
}
@override
RenderView get renderView => _renderView;
late RenderView _renderView;
@override
PipelineOwner get pipelineOwner => rootPipelineOwner;
/// Creates a [RenderView] object to be the root of the
/// [RenderObject] rendering tree, and initializes it so that it
/// will be rendered when the next frame is requested.
///
/// Called automatically when the binding is created.
RenderView initRenderView(FlutterView view) {
final RenderView renderView = RenderView(view: view);
rootPipelineOwner.rootNode = renderView;
addRenderView(renderView);
renderView.prepareInitialFrame();
return renderView;
}
@override
PipelineOwner createRootPipelineOwner() {
return PipelineOwner(
onSemanticsOwnerCreated: () {
renderView.scheduleInitialSemantics();
},
onSemanticsUpdate: (SemanticsUpdate update) {
renderView.updateSemantics(update);
},
onSemanticsOwnerDisposed: () {
renderView.clearSemantics();
},
);
}
/// Creates and initializes the binding. This function is
/// idempotent; calling it a second time will just return the
/// previously-created instance.
static TestRenderingFlutterBinding ensureInitialized({ VoidCallback? onErrors }) {
return _instance ?? TestRenderingFlutterBinding(onErrors: onErrors);
}
final List<FlutterErrorDetails> _errors = <FlutterErrorDetails>[];
/// A function called after drawing a frame if [FlutterError] caught any errors.
///
/// This function is expected to inspect these errors and decide whether they
/// are expected or not. Use [takeFlutterErrorDetails] to take one error at a
/// time, or [takeAllFlutterErrorDetails] to iterate over all errors.
VoidCallback? onErrors;
/// Returns the error least recently caught by [FlutterError] and removes it
/// from the list of captured errors.
///
/// Returns null if no errors were captures, or if the list was exhausted by
/// calling this method repeatedly.
FlutterErrorDetails? takeFlutterErrorDetails() {
if (_errors.isEmpty) {
return null;
}
return _errors.removeAt(0);
}
/// Returns all error details caught by [FlutterError] from least recently caught to
/// most recently caught, and removes them from the list of captured errors.
///
/// The returned iterable takes errors lazily. If, for example, you iterate over 2
/// errors, but there are 5 errors total, this binding will still fail the test.
/// Tests are expected to take and inspect all errors.
Iterable<FlutterErrorDetails> takeAllFlutterErrorDetails() sync* {
// sync* and yield are used for lazy evaluation. Otherwise, the list would be
// drained eagerly and allow a test pass with unexpected errors.
while (_errors.isNotEmpty) {
yield _errors.removeAt(0);
}
}
/// Returns all exceptions caught by [FlutterError] from least recently caught to
/// most recently caught, and removes them from the list of captured errors.
///
/// The returned iterable takes errors lazily. If, for example, you iterate over 2
/// errors, but there are 5 errors total, this binding will still fail the test.
/// Tests are expected to take and inspect all errors.
Iterable<dynamic> takeAllFlutterExceptions() sync* {
// sync* and yield are used for lazy evaluation. Otherwise, the list would be
// drained eagerly and allow a test pass with unexpected errors.
while (_errors.isNotEmpty) {
yield _errors.removeAt(0).exception;
}
}
EnginePhase phase = EnginePhase.composite;
/// Pumps a frame and runs its entire life cycle.
///
/// This method runs all of the [SchedulerPhase]s in a frame, this is useful
/// to test [SchedulerPhase.postFrameCallbacks].
void pumpCompleteFrame() {
final FlutterExceptionHandler? oldErrorHandler = FlutterError.onError;
FlutterError.onError = _errors.add;
try {
TestRenderingFlutterBinding.instance.handleBeginFrame(null);
TestRenderingFlutterBinding.instance.handleDrawFrame();
} finally {
FlutterError.onError = oldErrorHandler;
if (_errors.isNotEmpty) {
if (onErrors != null) {
onErrors!();
if (_errors.isNotEmpty) {
_errors.forEach(FlutterError.dumpErrorToConsole);
fail('There are more errors than the test inspected using TestRenderingFlutterBinding.takeFlutterErrorDetails.');
}
} else {
_errors.forEach(FlutterError.dumpErrorToConsole);
fail('Caught error while rendering frame. See preceding logs for details.');
}
}
}
}
@override
void drawFrame() {
assert(phase != EnginePhase.build, 'rendering_tester does not support testing the build phase; use flutter_test instead');
final FlutterExceptionHandler? oldErrorHandler = FlutterError.onError;
FlutterError.onError = _errors.add;
try {
rootPipelineOwner.flushLayout();
if (phase == EnginePhase.layout) {
return;
}
rootPipelineOwner.flushCompositingBits();
if (phase == EnginePhase.compositingBits) {
return;
}
rootPipelineOwner.flushPaint();
if (phase == EnginePhase.paint) {
return;
}
for (final RenderView renderView in renderViews) {
renderView.compositeFrame();
}
if (phase == EnginePhase.composite) {
return;
}
rootPipelineOwner.flushSemantics();
if (phase == EnginePhase.flushSemantics) {
return;
}
assert(phase == EnginePhase.flushSemantics || phase == EnginePhase.sendSemanticsUpdate);
} finally {
FlutterError.onError = oldErrorHandler;
if (_errors.isNotEmpty) {
if (onErrors != null) {
onErrors!();
if (_errors.isNotEmpty) {
_errors.forEach(FlutterError.dumpErrorToConsole);
fail('There are more errors than the test inspected using TestRenderingFlutterBinding.takeFlutterErrorDetails.');
}
} else {
_errors.forEach(FlutterError.dumpErrorToConsole);
fail('Caught error while rendering frame. See preceding logs for details.');
}
}
}
}
}
/// Place the box in the render tree, at the given size and with the given
/// alignment on the screen.
///
/// If you've updated `box` and want to lay it out again, use [pumpFrame].
///
/// Once a particular [RenderBox] has been passed to [layout], it cannot easily
/// be put in a different place in the tree or passed to [layout] again, because
/// [layout] places the given object into another [RenderBox] which you would
/// need to unparent it from (but that box isn't itself made available).
///
/// The EnginePhase must not be [EnginePhase.build], since the rendering layer
/// has no build phase.
///
/// If `onErrors` is not null, it is set as [TestRenderingFlutterBinding.onError].
void layout(
RenderBox box, { // If you want to just repump the last box, call pumpFrame().
BoxConstraints? constraints,
Alignment alignment = Alignment.center,
EnginePhase phase = EnginePhase.layout,
VoidCallback? onErrors,
}) {
assert(box.parent == null); // We stick the box in another, so you can't reuse it easily, sorry.
TestRenderingFlutterBinding.instance.renderView.child = null;
if (constraints != null) {
box = RenderPositionedBox(
alignment: alignment,
child: RenderConstrainedBox(
additionalConstraints: constraints,
child: box,
),
);
}
TestRenderingFlutterBinding.instance.renderView.child = box;
pumpFrame(phase: phase, onErrors: onErrors);
}
/// Pumps a single frame.
///
/// If `onErrors` is not null, it is set as [TestRenderingFlutterBinding.onError].
void pumpFrame({ EnginePhase phase = EnginePhase.layout, VoidCallback? onErrors }) {
assert(TestRenderingFlutterBinding.instance.renderView.child != null); // call layout() first!
if (onErrors != null) {
TestRenderingFlutterBinding.instance.onErrors = onErrors;
}
TestRenderingFlutterBinding.instance.phase = phase;
TestRenderingFlutterBinding.instance.drawFrame();
}
class TestCallbackPainter extends CustomPainter {
const TestCallbackPainter({ required this.onPaint });
final VoidCallback onPaint;
@override
void paint(Canvas canvas, Size size) {
onPaint();
}
@override
bool shouldRepaint(TestCallbackPainter oldPainter) => true;
}
class RenderSizedBox extends RenderBox {
RenderSizedBox(this._size);
final Size _size;
@override
double computeMinIntrinsicWidth(double height) {
return _size.width;
}
@override
double computeMaxIntrinsicWidth(double height) {
return _size.width;
}
@override
double computeMinIntrinsicHeight(double width) {
return _size.height;
}
@override
double computeMaxIntrinsicHeight(double width) {
return _size.height;
}
@override
bool get sizedByParent => true;
@override
void performResize() {
size = constraints.constrain(_size);
}
@override
void performLayout() { }
@override
bool hitTestSelf(Offset position) => true;
}
class FakeTickerProvider implements TickerProvider {
@override
Ticker createTicker(TickerCallback onTick, [ bool disableAnimations = false ]) {
return FakeTicker();
}
}
class FakeTicker implements Ticker {
@override
bool muted = false;
@override
void absorbTicker(Ticker originalTicker) { }
@override
String? get debugLabel => null;
@override
bool get isActive => throw UnimplementedError();
@override
bool get isTicking => throw UnimplementedError();
@override
bool get scheduled => throw UnimplementedError();
@override
bool get shouldScheduleTick => throw UnimplementedError();
@override
void dispose() { }
@override
void scheduleTick({ bool rescheduling = false }) { }
@override
TickerFuture start() {
throw UnimplementedError();
}
@override
void stop({ bool canceled = false }) { }
@override
void unscheduleTick() { }
@override
String toString({ bool debugIncludeStack = false }) => super.toString();
@override
DiagnosticsNode describeForError(String name) {
return DiagnosticsProperty<Ticker>(name, this, style: DiagnosticsTreeStyle.errorProperty);
}
}
class TestClipPaintingContext extends PaintingContext {
TestClipPaintingContext() : this._(ContainerLayer());
TestClipPaintingContext._(this._containerLayer) : super(_containerLayer, Rect.zero);
final ContainerLayer _containerLayer;
@override
ClipRectLayer? pushClipRect(
bool needsCompositing,
Offset offset,
Rect clipRect,
PaintingContextCallback painter, {
Clip clipBehavior = Clip.hardEdge,
ClipRectLayer? oldLayer,
}) {
this.clipBehavior = clipBehavior;
return null;
}
Clip clipBehavior = Clip.none;
@mustCallSuper
void dispose() {
_containerLayer.dispose();
}
}
class TestPushLayerPaintingContext extends PaintingContext {
TestPushLayerPaintingContext() : super(ContainerLayer(), Rect.zero);
final List<ContainerLayer> pushedLayers = <ContainerLayer>[];
@override
void pushLayer(
ContainerLayer childLayer,
PaintingContextCallback painter,
Offset offset, {
Rect? childPaintBounds
}) {
pushedLayers.add(childLayer);
super.pushLayer(childLayer, painter, offset, childPaintBounds: childPaintBounds);
}
}
// Absorbs errors that don't have "overflowed" in their error details.
void absorbOverflowedErrors() {
final Iterable<FlutterErrorDetails> errorDetails = TestRenderingFlutterBinding.instance.takeAllFlutterErrorDetails();
final Iterable<FlutterErrorDetails> filtered = errorDetails.where((FlutterErrorDetails details) {
return !details.toString().contains('overflowed');
});
if (filtered.isNotEmpty) {
filtered.forEach(FlutterError.reportError);
}
}
// Reports any FlutterErrors.
void expectNoFlutterErrors() {
final Iterable<FlutterErrorDetails> errorDetails = TestRenderingFlutterBinding.instance.takeAllFlutterErrorDetails();
errorDetails.forEach(FlutterError.reportError);
}
RenderConstrainedBox get box200x200 =>
RenderConstrainedBox(additionalConstraints: const BoxConstraints.tightFor(height: 200.0, width: 200.0));