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Extension methods for `package:vm_service`, used to make requests a Dart Development Service (DDS) instance.
Last release 1 years ago
08 Aug 2025
Release timing varies
gaps range from 2 weeks to 10 months
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notes for 8 of 15 stable releases
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no release was ever pulled
5 years old
15 releases · first in 2022
Breaking change: A number of static errors that should have been detected and reported were not supported in 2.0.0. These are reported now, which mean…
This is a minor version release. The team's focus was mostly on improving performance and stability after the large changes in Dart 2.0.0. Notable changes:
We've introduced a dedicated syntax for declaring a mixin. Instead of the
class keyword, it uses mixin:
mixin SetMixin<E> implements Set<E> {
...
}
The new syntax also enables super calls inside mixins.
Integer literals now work in double contexts. When passing a literal number to
a function that expects a double, you no longer need an explicit .0 at the
end of the number. In releases before 2.1, you need code like this when
setting a double like fontSize:
TextStyle(fontSize: 18.0)
Now you can remove the .0:
TextStyle(fontSize: 18)
In releases before 2.1, fontSize : 18 causes a static error. This was a
common mistake and source of friction.
Breaking change: A number of static errors that should have been detected and reported were not supported in 2.0.0. These are reported now, which means existing incorrect code may show new errors.
dart:core now exports Future and Stream. You no longer need to import
dart:async to use those very common types.
Introduced a new syntax for mixin declarations.
mixin SetMixin<E> implements Set<E> {
...
}
Most classes that are intended to be used as mixins are intended to only be
used as mixins. The library author doesn't want users to be able to construct
or subclass the class. The new syntax makes that intent clear and enforces it
in the type system. It is an error to extend or construct a type declared
using mixin. (You can implement it since mixins expose an implicit
interface.)
Over time, we expect most mixin declarations to use the new syntax. However, if you have a "mixin" class where users are extending or constructing it, note that moving it to the new syntax is a breaking API change since it prevents users from doing that. If you have a type like this that is a mixin as well as being a concrete class and/or superclass, then the existing syntax is what you want.
If you need to use a super inside a mixin, the new syntax is required. This
was previously only allowed with the experimental --supermixins flag because
it has some complex interactions with the type system. The new syntax
addresses those issues and lets you use super calls by declaring the
superclass constraint your mixin requires:
class Superclass {
superclassMethod() {
print("in superclass");
}
}
mixin SomeMixin on Superclass {
mixinMethod() {
// This is OK:
super.superclassMethod();
}
}
class GoodSub extends Superclass with SomeMixin {}
class BadSub extends Object with SomeMixin {}
// Error: Since the super() call in mixinMethod() can't find a
// superclassMethod() to call, this is prohibited.
Even if you don't need to use super calls, the new mixin syntax is good
because it clearly expresses that you intend the type to be mixed in.
Allow integer literals to be used in double contexts. An integer literal used in a place where a double is required is now interpreted as a double value. The numerical value of the literal needs to be precisely representable as a double value.
Integer literals compiled to JavaScript are now allowed to have any value that
can be exactly represented as a JavaScript Number. They were previously
limited to such numbers that were also representable as signed 64-bit
integers.
(Breaking) A number of static errors that should have been detected and reported were not supported in 2.0.0. These are reported now, which means existing incorrect code may show new errors:
Setters with the same name as the enclosing class aren't allowed. (Issue 34225.) It is not allowed to have a class member with the same name as the enclosing class:
class A {
set A(int x) {}
}
Dart 2.0.0 incorrectly allows this for setters (only). Dart 2.1.0 rejects it.
To fix: This is unlikely to break anything, since it violates all style guides anyway.
Constant constructors cannot redirect to non-constant constructors. (Issue 34161.) It is not allowed to have a constant constructor that redirects to a non-constant constructor:
class A {
const A.foo() : this(); // Redirecting to A()
A() {}
}
Dart 2.0.0 incorrectly allows this. Dart 2.1.0 rejects it.
To fix: Make the target of the redirection a properly const constructor.
Abstract methods may not unsoundly override a concrete method. (Issue 32014.) Concrete methods must be valid implementations of their interfaces:
class A {
num get thing => 2.0;
}
abstract class B implements A {
int get thing;
}
class C extends A with B {}
// 'thing' from 'A' is not a valid override of 'thing' from 'B'.
main() {
print(new C().thing.isEven); // Expects an int but gets a double.
}
Dart 2.0.0 allows unsound overrides like the above in some cases. Dart 2.1.0 rejects them.
To fix: Relax the type of the invalid override, or tighten the type of the overridden method.
Classes can't implement FutureOr. (Issue 33744.) Dart doesn't allow classes to implement the FutureOr type:
class A implements FutureOr<Object> {}
Dart 2.0.0 allows classes to implement FutureOr. Dart 2.1.0 does not.
To fix: Don't do this.
Type arguments to generic typedefs must satisfy their bounds. (Issue 33308.) If a parameterized typedef specifies a bound, actual arguments must be checked against it:
class A<X extends int> {}
typedef F<Y extends int> = A<Y> Function();
F<num> f = null;
Dart 2.0.0 allows bounds violations like F<num> above. Dart 2.1.0 rejects
them.
To fix: Either remove the bound on the typedef parameter, or pass a valid argument to the typedef.
Constructor invocations must use valid syntax, even with optional new.
(Issue 34403.) Type arguments to generic named constructors go after the
class name, not the constructor name, even when used without an explicit
new:
class A<T> {
A.foo() {}
}
main() {
A.foo<String>(); // Incorrect syntax, was accepted in 2.0.0.
A<String>.foo(); // Correct syntax.
}
Dart 2.0.0 accepts the incorrect syntax when the new keyword is left out.
Dart 2.1.0 correctly rejects this code.
To fix: Move the type argument to the correct position after the class name.
Instance members should shadow prefixes. (Issue 34498.) If the same name is used as an import prefix and as a class member name, then the class member name takes precedence in the class scope.
import 'dart:core';
import 'dart:core' as core;
class A {
core.List get core => null; // "core" refers to field, not prefix.
}
Dart 2.0.0 incorrectly resolves the use of core in core.List to the prefix
name. Dart 2.1.0 correctly resolves this to the field name.
To fix: Change the prefix name to something which does not clash with the instance member.
Implicit type arguments in extends clauses must satisfy the class bounds.
(Issue 34532.) Implicit type arguments for generic classes are computed if
not passed explicitly, but when used in an extends clause they must be
checked for validity:
class Foo<T> {}
class Bar<T extends Foo<T>> {}
class Baz extends Bar {} // Should error because Bar completes to Bar<Foo>
Dart 2.0.0 accepts the broken code above. Dart 2.1.0 rejects it.
To fix: Provide explicit type arguments to the superclass that satisfy the bound for the superclass.
Mixins must correctly override their superclasses. (Issue 34235.) In some rare cases, combinations of uses of mixins could result in invalid overrides not being caught:
class A {
num get thing => 2.0;
}
class M1 {
int get thing => 2;
}
class B = A with M1;
class M2 {
num get thing => 2.0;
}
class C extends B with M2 {} // 'thing' from 'M2' not a valid override.
main() {
M1 a = new C();
print(a.thing.isEven); // Expects an int but gets a double.
}
Dart 2.0.0 accepts the above example. Dart 2.1.0 rejects it.
To fix: Ensure that overriding methods are correct overrides of their superclasses, either by relaxing the superclass type, or tightening the subclass/mixin type.
dart:asyncstream.take(0).drain(value) would not correctly
forward the value through the returned Future.StreamTransformer.fromBind constructor.Stream.fromIterable to send a done event after the error when the
iterator's moveNext throws, and handle if the current getter throws (issue
33431).dart:coreHashMap.fromEntries and LinkedHashmap.fromEntries constructors.ArgumentError.checkNotNull utility method.Uri parsing more permissive about [ and ] occurring in the path,
query or fragment, and # occurring in fragment.Future and Stream from dart:core.&, | and ^ to bool.UnmodifiableMapMixin. Some maps intended to be
unmodifiable incorrectly allowed new methods added in Dart 2 to succeed.provisional annotation and the Provisional annotation
class. These should have been removed before releasing Dart 2.0, and they have
no effect.dart:htmlFixed Service Workers and any Promise/Future API with a Dictionary parameter.
APIs in dart:html (that take a Dictionary) will receive a Dart Map parameter. The Map parameter must be converted to a Dictionary before passing to the browser's API. Before this change, any Promise/Future API with a Map/Dictionary parameter never called the Promise and didn't return a Dart Future - now it does.
This caused a number of breaks especially in Service Workers (register, etc.). Here is a complete list of the fixed APIs:
BackgroundFetchManager
Future<BackgroundFetchRegistration> fetch(String id, Object requests, [Map options])CacheStorage
Future match(/*RequestInfo*/ request, [Map options])CanMakePayment
Future<List<Client>> matchAll([Map options])CookieStore
Future getAll([Map options])Future set(String name, String value, [Map options])CredentialsContainer
Future get([Map options])Future create([Map options])ImageCapture
Future setOptions(Map photoSettings)MediaCapabilities
Future<MediaCapabilitiesInfo> decodingInfo(Map configuration)Future<MediaCapabilitiesInfo> encodingInfo(Map configuration)MediaStreamTrack
Future applyConstraints([Map constraints])Navigator
Future requestKeyboardLock([List<String> keyCodes])Future requestMidiAccess([Map options])Future share([Map data])OffscreenCanvas
Future<Blob> convertToBlob([Map options])PaymentInstruments
Future set(String instrumentKey, Map details)Permissions
Future<PermissionStatus> query(Map permission)Future<PermissionStatus> request(Map permissions)Future<PermissionStatus> revoke(Map permission)PushManager
Future permissionState([Map options])Future<PushSubscription> subscribe([Map options])RtcPeerConnection
Changed:
Future createAnswer([options_OR_successCallback,
RtcPeerConnectionErrorCallback failureCallback,
Map mediaConstraints])
to:
Future<RtcSessionDescription> createAnswer([Map options])
Changed:
Future createOffer([options_OR_successCallback,
RtcPeerConnectionErrorCallback failureCallback,
Map rtcOfferOptions])
to:
Future<RtcSessionDescription> createOffer([Map options])
Changed:
Future setLocalDescription(Map description,
VoidCallback successCallback,
[RtcPeerConnectionErrorCallback failureCallback])
to:
Future setLocalDescription(Map description)
Changed:
Future setLocalDescription(Map description,
VoidCallback successCallback,
[RtcPeerConnectionErrorCallback failureCallback])
to:
Future setRemoteDescription(Map description)
ServiceWorkerContainer
Future<ServiceWorkerRegistration> register(String url, [Map options])ServiceWorkerRegistration
Future<List<Notification>> getNotifications([Map filter])Future showNotification(String title, [Map options])VRDevice
Future requestSession([Map options])Future supportsSession([Map options])VRSession
Future requestFrameOfReference(String type, [Map options])Window
Future fetch(/*RequestInfo*/ input, [Map init])WorkerGlobalScope
Future fetch(/*RequestInfo*/ input, [Map init])In addition, exposed Service Worker "self" as a static getter named "instance". The instance is exposed on four different Service Worker classes and can throw a InstanceTypeError if the instance isn't of the class expected (WorkerGlobalScope.instance will always work and not throw):
SharedWorkerGlobalScope.instanceDedicatedWorkerGlobalScope.instanceServiceWorkerGlobalScope.instanceWorkerGlobalScope.instancedart:io(Breaking) Duplicate keys in a const map are not allowed and produce a compile-time error. Dart2js used to report this as a warning before. This was already an error in dartanalyzer and DDC and will be an error in other tools in the future as well.
Added -O flag to tune optimization levels. For more details run
dart2js -h -v.
We recommend to enable optimizations using the -O flag instead of individual
flags for each optimization. This is because the -O flag is intended to be
stable and continue to work in future versions of dart2js, while individual
flags may come and go.
At this time we recommend to test and debug with -O1 and to deploy with
-O3.
Bumped the linter to 0.1.70 which includes the following new lints:
avoid_returning_null_for_voidsort_pub_dependenciesprefer_mixinavoid_implementing_value_typesflutter_style_todosavoid_void_asyncprefer_void_to_nulland improvements:
prefer_iterable_whereType.await_only_futuresnull_closuressort_constructors_first to apply to all members.unnecessary_this to work on field initializers.unawaited_futures to ignore assignments within cascades.invariant_booleans.unawaited_futures.unawaited_futures to check cascades.void_checks (allowing T Function() to be assigned to
void Function()).lines_longer_than_80_chars.--checked flag to pub run to --enable-asserts.--packages-dir flag is now ignored.One column per quarter.
DdsExtension.getAvailableCachedCpuSamples and
DdsExtension.getCachedCpuSamples methods.Require dart sdk v. 3.5.0 or higher.
DdsExtension.onTimerEventWithHistory.DdsExtension.on*EventWithHistory stream
contain an incorrect set of events.package:async.Update vm_service to >=14.0.0 <16.0.0.
vm_service to >=14.0.0 <16.0.0.The Dart 1.0 syntax is supported but deprecated.
This is the first major version release of Dart since 1.0.0, so it contains many significant changes across all areas of the platform. Large changes include:
(Breaking) The unsound optional static type system has been replaced with a sound static type system using type inference and runtime checks. This was formerly called "strong mode" and only used by the Dart for web products. Now it is the one official static type system for the entire platform and replaces the previous "checked" and "production" modes.
(Breaking) Functions marked async now run synchronously until the first
await statement. Previously, they would return to the event loop once at the
top of the function body before any code runs (issue 30345).
(Breaking) Constants in the core libraries have been renamed from
SCREAMING_CAPS to lowerCamelCase.
(Breaking) Many new methods have been added to core library classes. If you implement the interfaces of these classes, you will need to implement the new methods.
(Breaking) "dart:isolate" and "dart:mirrors" are no longer supported when using Dart for the web. They are still supported in the command-line VM.
(Breaking) Pub's transformer-based build system has been replaced by a new build system.
The new keyword is optional and can be omitted. Likewise, const can be
omitted inside a const context (issue 30921).
Dartium is no longer maintained or supported.
"Strong mode" is now the official type system of the language.
The new keyword is optional and can be omitted. Likewise, const can be
omitted inside a const context.
A string in a part of declaration may now be used to refer to the library
this file is part of. A library part can now declare its library as either:
part of name.of.library;
Or:
part of "uriReferenceOfLibrary.dart";
This allows libraries with no library declarations (and therefore no name) to have parts, and it allows tools to easily find the library of a part file. The Dart 1.0 syntax is supported but deprecated.
Functions marked async now run synchronously until the first await
statement. Previously, they would return to the event loop once at the top of
the function body before any code runs (issue 30345).
The type void is now a Top type like dynamic, and Object. It also now
has new errors for being used where not allowed (such as being assigned to any
non-void-typed parameter). Some libraries (importantly, mockito) may need to
be updated to accept void values to keep their APIs working.
Future flattening is now done only as specified in the Dart 2.0 spec, rather
than more broadly. This means that the following code has an error on the
assignment to y.
test() {
Future<int> f;
var x = f.then<Future<List<int>>>((x) => []);
Future<List<int>> y = x;
}
Invocations of noSuchMethod() receive default values for optional args. The
following program used to print "No arguments passed", and now prints "First
argument is 3".
abstract class B {
void m([int x = 3]);
}
class A implements B {
noSuchMethod(Invocation i) {
if (i.positionalArguments.length == 0) {
print("No arguments passed");
} else {
print("First argument is ${i.positionalArguments[0]}");
}
}
}
void main() {
A().m();
}
Bounds on generic functions are invariant. The following program now issues an invalid override error (issue 29014):
class A {
void f<T extends int>() {}
}
class B extends A {
@override
void f<T extends num>() {}
}
Numerous corner case bugs around return statements in synchronous and asynchronous functions fixed. Specifically:
An empty return; in an async function with return type Future<Object> does
not report an error.
return exp; where exp has type void in an async function is now an error
unless the return type of the function is void or dynamic.
Mixed return statements of the form return; and return exp; are now
allowed when exp has type void.
A compile time error is emitted for any literal which cannot be exactly represented on the target platform. As a result, dart2js and DDC report errors if an integer literal cannot be represented exactly in JavaScript (issue 33282).
New member conflict rules have been implemented. Most cases of conflicting members with the same name are now static errors (issue 33235).
Replaced UPPER_CASE constant names with lowerCamelCase. For example,
HTML_ESCAPE is now htmlEscape.
The Web libraries were re-generated using Chrome 63 WebIDLs (details).
dart:asyncStream:
cast and castFrom.firstWhere, lastWhere, and singleWhere to return Future<T>
and added an optional T orElse() callback.StreamTransformer: added cast and castFrom.StreamTransformerBase: new class.Timer: added tick property.Zone
bindBinaryCallbackGuarded, bindCallbackGuarded, and
bindUnaryCallbackGuarded.Zone.ROOT to Zone.root.defaultValue parameter on Stream.firstWhere and
Stream.lastWhere.dart:cliwaitFor: function that suspends a stack to wait for a Future to complete.dart:collectionMapBase: added mapToString.LinkedHashMap no longer implements HashMapLinkedHashSet no longer implements HashSet.of constructor to Queue, ListQueue, DoubleLinkedQueue,
HashSet, LinkedHashSet, SplayTreeSet, Map, HashMap, LinkedHashMap,
SplayTreeMap.Maps class. Extend MapBase or mix in MapMixin instead to provide
map method implementations for a class.Document method getCSSCanvasContext and property
supportsCssCanvasContext.Element property xtag no longer supported in browsers.ServiceWorker class.MessageChannel and MessagePort addEventListener
automatically calls start method to receive queued messages.dart:convertBase64Codec.decode return type is now Uint8List.JsonUnsupportedObjectError: added partialResult propertyLineSplitter now implements StreamTransformer<String, String> instead of
Converter. It retains Converter methods convert and
startChunkedConversion.Utf8Decoder when compiled with dart2js uses the browser's TextDecoder in
some common cases for faster decoding.ASCII, BASE64, BASE64URI, JSON, LATIN1 and UTF8 to
ascii, base64, base64Uri, json, latin1 and utf8.HtmlEscapeMode constants UNKNOWN, ATTRIBUTE, SQ_ATTRIBUTE
and ELEMENT to unknown, attribute, sqAttribute and elements.jsonEncode, jsonDecode, base64Encode, base64UrlEncode and
base64Decode top-level functions.encode on AsciiCodec and Latin1Codec, and
convert on AsciiEncoder, Latin1Encoder, to Uint8List.utf8.decoder.fuse(json.decoder) to ignore leading Unicode BOM.dart:coreBigInt class added to support integers greater than 64-bits.proxy annotation.Provisional class and provisional field.pragma annotation.RegExp added static escape function.Uri class now correctly handles paths while running on Node.js on
Windows.Iterable added members cast, castFrom, followedBy and whereType.Iterable.singleWhere added orElse parameter.List added + operator, first and last setters, and indexWhere and
lastIndexWhere methods, and static copyRange and writeIterable
methods.Map added fromEntries constructor.Map added addEntries, cast, entries, map, removeWhere, update
and updateAll members.MapEntry: new class used by Map.entries.IterableBase, ListBase, SetBase or
MapBase (or uses the corresponding mixins) from dart:collection, the new
members are implemented automatically.of constructor to List, Set, Map.double.INFINITY, double.NEGATIVE_INFINITY, double.NAN,
double.MAX_FINITE and double.MIN_POSITIVE to double.infinity,
double.negativeInfinity, double.nan, double.maxFinite and
double.minPositive.DateTime to lower case: MONDAY through
SUNDAY, DAYS_PER_WEEK (as daysPerWeek), JANUARY through DECEMBER and
MONTHS_PER_YEAR (as monthsPerYear).Duration to lower case:
MICROSECONDS_PER_MILLISECOND to microsecondsPerMillisecond,
MILLISECONDS_PER_SECOND to millisecondsPerSecond, SECONDS_PER_MINUTE to
secondsPerMinute, MINUTES_PER_HOUR to minutesPerHour, HOURS_PER_DAY to
hoursPerDay, MICROSECONDS_PER_SECOND to microsecondsPerSecond,
MICROSECONDS_PER_MINUTE to microsecondsPerMinute, MICROSECONDS_PER_HOUR
to microsecondsPerHour, MICROSECONDS_PER_DAY to microsecondsPerDay,
MILLISECONDS_PER_MINUTE to millisecondsPerMinute, MILLISECONDS_PER_HOUR
to millisecondsPerHour, MILLISECONDS_PER_DAY to millisecondsPerDay,
SECONDS_PER_HOUR to secondsPerHour, SECONDS_PER_DAY to secondsPerDay,
MINUTES_PER_DAY to minutesPerDay, and ZERO to zero.typeArguments to Invocation class.Invocation
objects directly, without going through noSuchMethod.unaryMinus and empty constant symbols on the Symbol class.UriData.dataAsBytes to Uint8List.tryParse static method to int, double, num, BigInt, Uri and
DateTime.onError parameter on int.parse, double.parse and num.parse.NoSuchMethodError constructor.int.parse on the VM no longer accepts unsigned hexadecimal numbers greater
than or equal to 2**63 when not prefixed by 0x. (SDK issue
32858)dart:developerFlow class added.Timeline.startSync and Timeline.timeSync now accepts an optional parameter
flow of type Flow. The flow parameter is used to generate flow timeline
events that are enclosed by the slice described by
Timeline.{start,finish}Sync and Timeline.timeSync.<!-- Still need entries for all changes to dart:html since 1.x -->
dart:htmlquery and queryAll. Use querySelector and
querySelectorAll.dart:ioHttpStatus added UPGRADE_REQUIRED.IOOverrides and HttpOverrides added to aid in writing tests that wish to
mock varios dart:io objects.Platform.operatingSystemVersion added that gives a platform-specific String
describing the version of the operating system.ProcessStartMode.INHERIT_STDIO added, which allows a child process to
inherit the parent's stdio handles.RawZLibFilter added for low-level access to compression and decompression
routines.SecureSocket, SecurityContext, and X509Certificate
to be consistent across all platforms. All SecureSocket, SecurityContext,
and X509Certificate properties and methods are now supported on iOS and OSX.SecurityContext.alpnSupported deprecated as ALPN is now supported on all
platforms.SecurityContext: added withTrustedRoots named optional parameter
constructor, which defaults to false.timeout parameter to Socket.connect, RawSocket.connect,
SecureSocket.connect and RawSecureSocket.connect. If a connection attempt
takes longer than the duration specified in timeout, a SocketException
will be thrown. Note: if the duration specified in timeout is greater than
the OS level timeout, a timeout may occur sooner than specified in timeout.Stdin.hasTerminal added, which is true if stdin is attached to a terminal.WebSocket added static userAgent property.RandomAccessFile.close returns Future<void>IOOverrides.socketConnect.ZLibOptions, FileMode, FileLock,
FileSystemEntityType, FileSystemEvent, ProcessStartMode,
ProcessSignal, InternetAddressType, InternetAddress, SocketDirection,
SocketOption, RawSocketEvent, and StdioType, and deprecated the old
SCREAMING_CAPS constants.zlib, gzip, and
systemEncoding, and deprecated the old SCREAMING_CAPS top-level constants.FileMode constants READ, WRITE, APPEND,
WRITE_ONLY, and WRITE_ONLY_APPEND. Please use e.g. FileMode.read
instead.X509Certificate.der, X509Certificate.pem, and
X509Certificate.sha1.FileSystemEntity.fromRawPath constructor to allow for the creation of
FileSystemEntity using Uint8List buffers.HttpStatus, HttpHeaders,
ContentType, HttpClient, WebSocketStatus, CompressionOptions, and
WebSocket. The SCREAMING_CAPS constants are marked deprecated. Note that
HttpStatus.CONTINUE is now HttpStatus.continue_, and that e.g.
HttpHeaders.FIELD_NAME is now HttpHeaders.fieldNameHeader.Platform.packageRoot, which is only used for packages/
directory resolution which is no longer supported. It will now always return
null, which is a value that was always possible for it to return previously.HttpClient.connectionTimeout.{Socket,RawSocket,SecureSocket}.startConnect. These return a
ConnectionTask, which can be used to cancel an in-flight connection attempt.dart:isolateIsolate.spawn take a type parameter representing the argument type of
the provided function. This allows functions with arguments types other than
Object in strong mode.IMMEDIATE and BEFORE_NEXT_EVENT on Isolate to immediate and
beforeNextEvent.Isolate.packageRoot, which is only used for packages/ directory
resolution which is no longer supported. It will now always return null, which
is a value that was always possible for it to return previously.packageRoot parameter in Isolate.spawnUri, which is was
previously used only for packages/ directory resolution. That style of
resolution is no longer supported in Dart 2.<!-- Still need entries for all changes to dart:js since 1.x -->
dart.mathE, LN10, LN, LOG2E, LOG10E, PI, SQRT1_2 and SQRT2 to
e, ln10, ln, log2e, log10e, pi, sqrt1_2 and sqrt2.dart.mirrorsIsolateMirror.loadUri, which allows dynamically loading additional
code.MirrorsUsed as deprecated. The MirrorsUsed annotation was only used
to inform the dart2js compiler about how mirrors were used, but dart2js no
longer supports the mirrors library altogether.<!-- Still need entries for all changes to dart:svg since 1.x -->
dart:typed_dataUnmodifiable view classes over all List types.BYTES_PER_ELEMENT to bytesPerElement on all typed data lists.XXXX through WWWW on Float32x4 and Int32x4 to
lower-case xxxx through wwww.Endinanness to Endian and its constants from BIG_ENDIAN,
LITTLE_ENDIAN and HOST_ENDIAN to little, big and host.<!-- Still need entries for all changes to dart:web_audio,web_gl,web_sql since 1.x -->
Support for MIPS has been removed.
Dart int is now restricted to 64 bits. On overflow, arithmetic operations
wrap around, and integer literals larger than 64 bits are not allowed. See
https://github.com/dart-lang/sdk/blob/main/docs/language/informal/int64.md
for details.
The Dart VM no longer attempts to perform packages/ directory resolution
(for loading scripts, and in Isolate.resolveUri). Users relying on
packages/ directories should switch to .packages files.
Expose JavaScript Promise APIs using Dart futures. For example,
BackgroundFetchManager.get is defined as:
Future<BackgroundFetchRegistration> get(String id)
It can be used like:
BackgroundFetchRegistration result = await fetchMgr.get('abc');
The underlying JS Promise-to-Future mechanism will be exposed as a public API in the future.
dartdevc will no longer throw an error from is checks that return a
different result in weak mode (SDK issue 28988). For example:
main() {
List l = [];
// Prints "false", does not throw.
print(l is List<String>);
}
Failed as casts on Iterable<T>, Map<T>, Future<T>, and Stream<T> are
no longer ignored. These failures were ignored to make it easier to migrate
Dart 1 code to strong mode, but ignoring them is a hole in the type system.
This closes part of that hole. (We still need to stop ignoring "as" cast
failures on function types, and implicit cast failures on the above types and
function types.)
dart2js now compiles programs with Dart 2.0 semantics. Apps are expected to be
bigger than before, because Dart 2.0 has many more implicit checks (similar to
the --checked flag in Dart 1.0).
We exposed a --omit-implicit-checks flag which removes most of the extra
implicit checks. Only use this if you have enough test coverage to know that
the app will work well without the checks. If a check would have failed and it
is omitted, your app may crash or behave in unexpected ways. This flag is
similar to --trust-type-annotations in Dart 1.0.
dart2js replaced its front-end with the common front-end (CFE). Thanks to the CFE, dart2js errors are more consistent with all other Dart tools.
dart2js replaced its source-map implementation. There aren't any big differences, but more data is emitted for synthetic code generated by the compiler.
dart:mirrors support was removed. Frameworks are encouraged to use
code-generation instead. Conditional imports indicate that mirrors are not
supported, and any API in the mirrors library will throw at runtime.
The generated output of dart2js can now be run as a webworker.
dart:isolate support was removed. To launch background tasks, please use
webworkers instead. APIs for webworkers can be accessed from dart:html or
JS-interop.
dart2js no longer supports the --package-root flag. This flag was deprecated
in favor of --packages long ago.
The analyzer will no longer issue a warning when a generic type parameter is used as the type in an instance check. For example:
test<T>() {
print(3 is T); // No warning
}
New static checking of @visibleForTesting elements. Accessing a method,
function, class, etc. annotated with @visibleForTesting from a file not in
a test/ directory will result in a new hint (issue 28273).
Static analysis now respects functions annotated with @alwaysThrows (issue
31384).
New hints added:
NULL_AWARE_BEFORE_OPERATOR when an operator is used after a null-aware
access. For example:
x?.a - ''; // HINT
NULL_AWARE_IN_LOGICAL_OPERATOR when an expression with null-aware access
is used as a condition in logical operators. For example:
x.a || x?.b; // HINT
The command line analyzer (dartanalyzer) and the analysis server no longer
treat directories named packages specially. Previously they had ignored
these directories - and their contents - from the point of view of analysis.
Now they'll be treated just as regular directories. This special-casing of
packages directories was to support using symlinks for package: resolution;
that functionality is now handled by .packages files.
New static checking of duplicate shown or hidden names in an export directive (issue 33182).
The analysis server will now only analyze code in Dart 2 mode ('strong mode').
It will emit warnings for analysis options files that have
strong-mode: false set (and will emit a hint for strong-mode: true, which
is no longer necessary).
The dartanalyzer --strong flag is now deprecated and ignored. The
command-line analyzer now only analyzes code in strong mode.
Support assert() in const constructor initializer lists.
Better formatting for multi-line strings in argument lists.
Force splitting an empty block as the then body of an if with an else.
Support metadata annotations on enum cases.
Add --fix to remove unneeded new and const keywords, and change : to
= before named parameter default values.
Change formatting rules around static methods to uniformly format code with
and without new and const.
Format expressions inside string interpolation.
Pub has a brand new version solver! It supports all the same features as the old version solver, but it's much less likely to stall out on difficult package graphs, and it's much clearer about why a solution can't be found when version solving fails.
Remove support for transformers, pub build, and pub serve. Use the [new
build system][transformers] instead.
There is now a default SDK constraint of <2.0.0 for any package with no
existing upper bound. This allows us to move more safely to 2.0.0. All new
packages published on pub will now require an upper bound SDK constraint so
future major releases of Dart don't destabilize the package ecosystem.
All SDK constraint exclusive upper bounds are now treated as though they allow
pre-release versions of that upper bound. For example, the SDK constraint
>=1.8.0 <2.0.0 now allows pre-release SDK versions such as 2.0.0-beta.3.0.
This allows early adopters to try out packages that don't explicitly declare
support for the new version yet. You can disable this functionality by setting
the PUB_ALLOW_PRERELEASE_SDK environment variable to false.
Allow depending on a package in a subdirectory of a Git repository. Git
dependencies may now include a path parameter, indicating that the package
exists in a subdirectory of the Git repository. For example:
dependencies:
foobar:
git:
url: git://github.com/dart-lang/multi_package_repo
path: pkg/foobar
Added an --executables option to pub deps command. This will list all
available executables that can be run with pub run.
The Flutter sdk source will now look for packages in
flutter/bin/cache/pkg/ as well as flutter/packages/. In particular, this
means that packages can depend on the sky_engine package from the sdk
source (issue 1775).
Pub now caches compiled packages and snapshots in the .dart_tool/pub
directory, rather than the .pub directory (issue 1795).
Other bug fixes and improvements.
readyToResumerequireUserPermissionToResumeBreaking change: HttpClient.close must be called for all clients or they will keep the Dart process alive until they time out. This fixes the handling…
pub now generates binstubs for packages that are globally activated so that
they can be put on the user's PATH and used as normal executables. See the
pub global activate documentation.
When using dart2js, deferred loading now works with multiple Dart apps on
the same page.
dart:async: Zone, ZoneDelegate, and ZoneSpecification added the
errorCallback function, which allows errors that have been programmatically
added to a Future or Stream to be intercepted.
dart:io:
Breaking change: HttpClient.close must be called for all clients or
they will keep the Dart process alive until they time out. This fixes the
handling of persistent connections. Previously, the client would shut down
immediately after a request.
Breaking change: HttpServer no longer compresses all traffic by
default. The new autoCompress property can be set to true to re-enable
compression.
dart:isolate: Isolate.spawnUri added the optional packageRoot argument,
which controls how it resolves package: URIs.
ClientNameDdsExtension.getClientNameDdsExtension.getLogHistorySizeDdsExtension.setClientNameDdsExtension.setLogHistorySizeDdsExtension.requirePermissionToResumeSizeUpdated vm_service version to ^14.0.0.
vm_service version to ^14.0.0.Updated vm_service version to ^13.0.0.
vm_service version to ^13.0.0.Updated vm_service version to ^12.0.0.
vm_service version to ^12.0.0.DdsExtension.postEvent.DdsExtension.getPerfettoVMTimelineWithCpuSamples.vm_service version to ^11.0.0.vm_service version to ^10.0.0.vm_service version to 9.0.0.package:dds/vm_service_extensions.dart into a standalone package.Nothing published for this version
Nothing published for this version
Nothing published for this version
Nothing published for this version
Nothing published for this version
Nothing published for this version
Nothing published for this version
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