blob: 23adcbc40ec00a431d396a172b43bd513d1e95b3 [file] [log] [blame]
// Copyright (c) 2012, the Dart project authors. Please see the AUTHORS file
// for details. 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:io';
import 'package:async/async.dart';
import 'package:path/path.dart' as p;
import 'package:test/test.dart';
import 'package:test_descriptor/test_descriptor.dart' as d;
import 'package:watcher/src/stat.dart';
import 'package:watcher/watcher.dart';
typedef WatcherFactory = Watcher Function(String directory);
/// Sets the function used to create the watcher.
set watcherFactory(WatcherFactory factory) {
_watcherFactory = factory;
}
/// The mock modification times (in milliseconds since epoch) for each file.
///
/// The actual file system has pretty coarse granularity for file modification
/// times. This means using the real file system requires us to put delays in
/// the tests to ensure we wait long enough between operations for the mod time
/// to be different.
///
/// Instead, we'll just mock that out. Each time a file is written, we manually
/// increment the mod time for that file instantly.
final _mockFileModificationTimes = <String, int>{};
late WatcherFactory _watcherFactory;
/// Creates a new [Watcher] that watches a temporary file or directory.
///
/// If [path] is provided, watches a subdirectory in the sandbox with that name.
Watcher createWatcher({String? path}) {
if (path == null) {
path = d.sandbox;
} else {
path = p.join(d.sandbox, path);
}
return _watcherFactory(path);
}
/// The stream of events from the watcher started with [startWatcher].
late StreamQueue<WatchEvent> _watcherEvents;
/// Whether the event stream has been closed.
///
/// If this is not done by a test (by calling [startClosingEventStream]) it will
/// be done automatically via [addTearDown] in [startWatcher].
var _hasClosedStream = true;
/// Creates a new [Watcher] that watches a temporary file or directory and
/// starts monitoring it for events.
///
/// If [path] is provided, watches a path in the sandbox with that name.
Future<void> startWatcher({String? path}) async {
mockGetModificationTime((path) {
final normalized = p.normalize(p.relative(path, from: d.sandbox));
// Make sure we got a path in the sandbox.
assert(p.isRelative(normalized) && !normalized.startsWith('..'),
'Path is not in the sandbox: $path not in ${d.sandbox}');
var mtime = _mockFileModificationTimes[normalized];
return DateTime.fromMillisecondsSinceEpoch(mtime ?? 0);
});
// We want to wait until we're ready *after* we subscribe to the watcher's
// events.
var watcher = createWatcher(path: path);
_watcherEvents = StreamQueue(watcher.events);
// Forces a subscription to the underlying stream.
unawaited(_watcherEvents.hasNext);
_hasClosedStream = false;
addTearDown(startClosingEventStream);
await watcher.ready;
}
/// Schedule closing the watcher stream after the event queue has been pumped.
///
/// This is necessary when events are allowed to occur, but don't have to occur,
/// at the end of a test. Otherwise, if they don't occur, the test will wait
/// indefinitely because they might in the future and because the watcher is
/// normally only closed after the test completes.
void startClosingEventStream() async {
if (_hasClosedStream) return;
_hasClosedStream = true;
await pumpEventQueue();
await _watcherEvents.cancel(immediate: true);
}
/// A list of [StreamMatcher]s that have been collected using
/// [_collectStreamMatcher].
List<StreamMatcher>? _collectedStreamMatchers;
/// Collects all stream matchers that are registered within [block] into a
/// single stream matcher.
///
/// The returned matcher will match each of the collected matchers in order.
StreamMatcher _collectStreamMatcher(void Function() block) {
var oldStreamMatchers = _collectedStreamMatchers;
var collectedStreamMatchers = _collectedStreamMatchers = <StreamMatcher>[];
try {
block();
return emitsInOrder(collectedStreamMatchers);
} finally {
_collectedStreamMatchers = oldStreamMatchers;
}
}
/// Either add [streamMatcher] as an expectation to [_watcherEvents], or collect
/// it with [_collectStreamMatcher].
///
/// [streamMatcher] can be a [StreamMatcher], a [Matcher], or a value.
Future _expectOrCollect(streamMatcher) {
var collectedStreamMatchers = _collectedStreamMatchers;
if (collectedStreamMatchers != null) {
collectedStreamMatchers.add(emits(streamMatcher));
return Future.sync(() {});
} else {
return expectLater(_watcherEvents, emits(streamMatcher));
}
}
/// Expects that [matchers] will match emitted events in any order.
///
/// [matchers] may be [Matcher]s or values, but not [StreamMatcher]s.
Future inAnyOrder(Iterable matchers) {
matchers = matchers.toSet();
return _expectOrCollect(emitsInAnyOrder(matchers));
}
/// Expects that the expectations established in either [block1] or [block2]
/// will match the emitted events.
///
/// If both blocks match, the one that consumed more events will be used.
Future allowEither(void Function() block1, void Function() block2) =>
_expectOrCollect(emitsAnyOf(
[_collectStreamMatcher(block1), _collectStreamMatcher(block2)]));
/// Allows the expectations established in [block] to match the emitted events.
///
/// If the expectations in [block] don't match, no error will be raised and no
/// events will be consumed. If this is used at the end of a test,
/// [startClosingEventStream] should be called before it.
Future allowEvents(void Function() block) =>
_expectOrCollect(mayEmit(_collectStreamMatcher(block)));
/// Returns a StreamMatcher that matches a [WatchEvent] with the given [type]
/// and [path].
Matcher isWatchEvent(ChangeType type, String path) {
return predicate((e) {
return e is WatchEvent &&
e.type == type &&
e.path == p.join(d.sandbox, p.normalize(path));
}, 'is $type $path');
}
/// Returns a [Matcher] that matches a [WatchEvent] for an add event for [path].
Matcher isAddEvent(String path) => isWatchEvent(ChangeType.ADD, path);
/// Returns a [Matcher] that matches a [WatchEvent] for a modification event for
/// [path].
Matcher isModifyEvent(String path) => isWatchEvent(ChangeType.MODIFY, path);
/// Returns a [Matcher] that matches a [WatchEvent] for a removal event for
/// [path].
Matcher isRemoveEvent(String path) => isWatchEvent(ChangeType.REMOVE, path);
/// Expects that the next event emitted will be for an add event for [path].
Future expectAddEvent(String path) =>
_expectOrCollect(isWatchEvent(ChangeType.ADD, path));
/// Expects that the next event emitted will be for a modification event for
/// [path].
Future expectModifyEvent(String path) =>
_expectOrCollect(isWatchEvent(ChangeType.MODIFY, path));
/// Expects that the next event emitted will be for a removal event for [path].
Future expectRemoveEvent(String path) =>
_expectOrCollect(isWatchEvent(ChangeType.REMOVE, path));
/// Consumes a modification event for [path] if one is emitted at this point in
/// the schedule, but doesn't throw an error if it isn't.
///
/// If this is used at the end of a test, [startClosingEventStream] should be
/// called before it.
Future allowModifyEvent(String path) =>
_expectOrCollect(mayEmit(isWatchEvent(ChangeType.MODIFY, path)));
/// Schedules writing a file in the sandbox at [path] with [contents].
///
/// If [contents] is omitted, creates an empty file. If [updateModified] is
/// `false`, the mock file modification time is not changed.
void writeFile(String path, {String? contents, bool? updateModified}) {
contents ??= '';
updateModified ??= true;
var fullPath = p.join(d.sandbox, path);
// Create any needed subdirectories.
var dir = Directory(p.dirname(fullPath));
if (!dir.existsSync()) {
dir.createSync(recursive: true);
}
File(fullPath).writeAsStringSync(contents);
if (updateModified) {
path = p.normalize(path);
_mockFileModificationTimes.update(path, (value) => value + 1,
ifAbsent: () => 1);
}
}
/// Schedules deleting a file in the sandbox at [path].
void deleteFile(String path) {
File(p.join(d.sandbox, path)).deleteSync();
}
/// Schedules renaming a file in the sandbox from [from] to [to].
void renameFile(String from, String to) {
File(p.join(d.sandbox, from)).renameSync(p.join(d.sandbox, to));
// Make sure we always use the same separator on Windows.
to = p.normalize(to);
_mockFileModificationTimes.update(to, (value) => value + 1,
ifAbsent: () => 1);
}
/// Schedules creating a directory in the sandbox at [path].
void createDir(String path) {
Directory(p.join(d.sandbox, path)).createSync();
}
/// Schedules renaming a directory in the sandbox from [from] to [to].
void renameDir(String from, String to) {
Directory(p.join(d.sandbox, from)).renameSync(p.join(d.sandbox, to));
}
/// Schedules deleting a directory in the sandbox at [path].
void deleteDir(String path) {
Directory(p.join(d.sandbox, path)).deleteSync(recursive: true);
}
/// Runs [callback] with every permutation of non-negative numbers for each
/// argument less than [limit].
///
/// Returns a set of all values returns by [callback].
///
/// [limit] defaults to 3.
Set<S> withPermutations<S>(S Function(int, int, int) callback, {int? limit}) {
limit ??= 3;
var results = <S>{};
for (var i = 0; i < limit; i++) {
for (var j = 0; j < limit; j++) {
for (var k = 0; k < limit; k++) {
results.add(callback(i, j, k));
}
}
}
return results;
}