![Alexander Thomas](/assets/img/avatar_default.png)
TBR=aadilmaan@google.com Change-Id: Ibe6b6e41cde9631f7aeaf354a1f27c130c9198d6 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/116521 Reviewed-by: Alexander Thomas <athom@google.com>
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Language
Core libraries
Dart VM
Tools
Pub
Linter
The Linter was updated to 0.1.97+1
, which includes:
- internal migration away from using analyzer
resolutionMap
- various fixes and improvements to anticipate support for extension-methods
- new lint:
camel_case_extensions
- rule template generation improvements
- new lint:
avoid_equals_and_hash_code_on_mutable_classes
- extended
avoid_slow_async_io
to flag asyncDirectory
methods
2.5.0 - 2019-09-10
Language
The set of operations allowed in constant expressions has been expanded as described in the constant update proposal. The control flow and spread collection features shipped in Dart 2.3 are now also supported in constants as described in the specification here.
Specifically, it is now valid to use the following operations in constant expressions under the appropriate conditions:
- Casts (
e as T
) and type tests (e is T
). - Comparisons to
null
, even for types which override the==
operator. - The
&
,|
, and^
binary operators on booleans. - The spread operators (
...
and...?
). - An
if
element in a collection literal.
// Example: these are now valid constants.
const Object i = 3;
const list = [i as int];
const set = {if (list is List<int>) ...list};
const map = {if (i is int) i : "int"};
In addition, the semantics of constant evaluation has been changed as follows:
- The
&&
operator only evaluates its second operand if the first evaluates to true. - The
||
operator only evaluates its second operand if the first evaluates to false. - The
??
operator only evaluates its second operand if the first evaluates to null. - The conditional operator (
e ? e1 : e2
) only evaluates one of the two branches, depending on the value of the first operand.
// Example: x is now a valid constant definition.
const String s = null;
const int x = (s == null) ? 0 : s.length;
Core libraries
-
Breaking change #36900: The following methods and properties across various core libraries, which used to declare a return type of
List<int>
, were updated to declare a return type ofUint8List
:BytesBuilder.takeBytes()
BytesBuilder.toBytes()
Datagram.data
File.readAsBytes()
(Future<Uint8List>
)File.readAsBytesSync()
InternetAddress.rawAddress
RandomAccessFile.read()
(Future<Uint8List>
)RandomAccessFile.readSync()
RawSocket.read()
Utf8Codec.encode()
(andUtf8Encoder.convert()
)
In addition, the following classes were updated to implement
Stream<Uint8List>
rather thanStream<List<int>>
:HttpRequest
Socket
Possible errors and how to fix them
-
The argument type 'Utf8Decoder' can't be assigned to the parameter type 'StreamTransformer<Uint8List, dynamic>'
type 'Utf8Decoder' is not a subtype of type 'StreamTransformer' of 'streamTransformer'"
You can fix these call sites by updating your code to use
StreamTransformer.bind()
instead ofStream.transform()
, like so:Before:
stream.transform(utf8.decoder)
After:utf8.decoder.bind(stream)
-
The argument type 'IOSink' can't be assigned to the parameter type 'StreamConsumer'
type '_IOSinkImpl' is not a subtype of type 'StreamConsumer' of 'streamConsumer'
You can fix these call sites by casting your stream instance to a
Stream<List<int>>
before calling.pipe()
on the stream, like so:Before:
stream.pipe(consumer)
After:stream.cast<List<int>>().pipe(consumer)
Finally, the following typed lists were updated to have their
sublist()
methods declare a return type that is the same as the source list:Int8List.sublist()
→Int8List
Int16List.sublist()
→Int16List
Int32List.sublist()
→Int32List
Int64List.sublist()
→Int64List
Int32x4List.sublist()
→Int32x4List
Float32List.sublist()
→Float32List
Float64List.sublist()
→Float64List
Float32x4List.sublist()
→Float32x4List
Float64x2List.sublist()
→Float64x2List
Uint8List.sublist()
→Uint8List
Uint8ClampedList.sublist()
→Uint8ClampedList
Uint16List.sublist()
→Uint16List
Uint32List.sublist()
→Uint32List
Uint64List.sublist()
→Uint64List
dart:async
- Add
value
anderror
constructors onStream
to allow easily creating single-value or single-error streams.
dart:core
-
Update
Uri
class to support RFC6874: "%25" or "%" can be appended to the end of a valid IPv6 representing a Zone Identifier. A valid zone ID consists of unreversed character or Percent encoded octet, which was defined in RFC3986. IPv6addrz = IPv6address "%25" ZoneID
dart:io
-
Breaking change #37192: The
Cookie
class's constructor'sname
andvalue
optional positional parameters are now mandatory. The signature changes from:Cookie([String name, String value])
to
Cookie(String name, String value)
However, it has not been possible to set
name
andvalue
to null since Dart 1.3.0 (2014) where a bug made it impossible. Any code not using both parameters or setting any to null would necessarily get a noSuchMethod exception at runtime. This change catches such erroneous uses at compile time. Since code could not previously correctly omit the parameters, this is not really a breaking change. -
Breaking change #37192: The
Cookie
class'sname
andvalue
setters now validates that the strings are made from the allowed character set and are not null. The constructor already made these checks and this fixes the loophole where the setters didn't also validate.
Dart VM
Tools
Pub
- Clean-up invalid git repositories in cache when fetching from git.
- Breaking change #36765: Packages published to pub.dev can no longer contain git dependencies. These packages will be rejected by the server.
Linter
The Linter was updated to 0.1.96
, which includes:
- fixed false positives in
unnecessary_parens
- various changes to migrate to preferred analyzer APIs
- rule test fixes
Dartdoc
Dartdoc was updated to 0.28.4
; this version includes several fixes and is based
on a newer version of the analyzer package.
2.4.1 - 2019-08-07
This is a patch release that fixes a performance regression in JIT mode, as well as a potential crash of our AOT compiler.
Dart VM
-
Fixed a performance regression where usage of
Int32List
could trigger repeated deoptimizations in JIT mode (Issue 37551). -
Fixed a bug where usage of a static getter with name
length
could cause a crash in our AOT compiler (Issue 35121).
Dart Dev Compiler (DDC)
Callbacks passed to JS and wrapped with allowInterop
or
allowInteropCaptureThis
are now strict about argument counts and argument
types. This may mean that tests which were previously passing and relying on
loose argument checking (too many or too few arguments, or arguments with too
specific types like List<Something>
instead of List<dynamic>
) may start
failing. This changes makes DDC behave more like dart2js with the default flags.
2.4.0 - 2019-06-27
Core libraries
dart:isolate
-
TransferableTypedData
class was added to facilitate faster cross-isolate communication ofUint8List
data. -
Breaking change:
Isolate.resolvePackageUri
will always throw anUnsupportedError
when compiled with dart2js or DDC. This was the only remaining API indart:isolate
that didn't automatically throw since we dropped support for this library in Dart 2.0.0. Note that the API already throws in dart2js if the API is used directly without manually setting up adefaultPackagesBase
hook.
dart:developer
- Exposed
result
,errorCode
anderrorDetail
getters inServiceExtensionResponse
to allow for better debugging of VM service extension RPC results.
dart:io
-
Fixed
Cookie
class interoperability with certain websites by allowing the cookie values to be the empty string (Issue 35804) and not stripping double quotes from the value (Issue 33327) in accordance with RFC 6265. -
#36971: The
HttpClientResponse
interface has been extended with the addition of a newcompressionState
getter, which specifies whether the body of a response was compressed when it was received and whether it has been automatically uncompressed viaHttpClient.autoUncompress
.As part of this change, a corresponding new enum was added to
dart:io
:HttpClientResponseCompressionState
.This is a breaking change for those implementing the
HttpClientResponse
interface as subclasses will need to implement the new getter.
dart:async
- Breaking change #36382:
The
await for
allowednull
as a stream due to a bug inStreamIterator
class. This bug has now been fixed.
dart:core
-
#36171: The
RegExp
interface has been extended with two new constructor named parameters:unicode:
(bool
, default:false
), for Unicode patternsdotAll:
(bool
, default:false
), to change the matching behavior of '.' to also match line terminating characters.
Appropriate properties for these named parameters have also been added so their use can be detected after construction.
In addition,
RegExp
methods that originally returnedMatch
objects now return a more specific subtype,RegExpMatch
, which adds two features:Iterable<String> groupNames
, a property that contains the names of all named capture groupsString namedGroup(String name)
, a method that retrieves the match for the given named capture group
This is a breaking change for implementers of the
RegExp
interface. Subclasses will need to add the new properties and may have to update the return types on overridden methods.
Language
- Breaking change #35097: Covariance of type variables used in super-interfaces is now enforced. For example, the following code was previously accepted and will now be rejected:
class A<X> {};
class B<X> extends A<void Function(X)> {};
- The identifier
async
can now be used in asynchronous and generator functions.
Dart for the Web
Dart Dev Compiler (DDC)
- Improve
NoSuchMethod
errors for failing dynamic calls. Now they include specific information about the nature of the error such as:- Attempting to call a null value.
- Calling an object instance with a null
call()
method. - Passing too few or too many arguments.
- Passing incorrect named arguments.
- Passing too few or too many type arguments.
- Passing type arguments to a non-generic method.
Tools
Linter
The Linter was updated to 0.1.91
, which includes the following changes:
- Fixed missed cases in
prefer_const_constructors
- Fixed
prefer_initializing_formals
to no longer suggest API breaking changes - Updated
omit_local_variable_types
to allow explicitdynamic
s - Fixed null-reference in
unrelated_type_equality_checks
- New lint:
unsafe_html
- Broadened
prefer_null_aware_operators
to work beyond local variables. - Added
prefer_if_null_operators
. - Fixed
prefer_contains
false positives. - Fixed
unnecessary_parenthesis
false positives. - Fixed
prefer_asserts_in_initializer_lists
false positives - Fixed
curly_braces_in_flow_control_structures
to handle more cases - New lint:
prefer_double_quotes
- New lint:
sort_child_properties_last
- Fixed
type_annotate_public_apis
false positive forstatic const
initializers
Pub
pub publish
will no longer warn about missing dependencies for import statements inexample/
.- OAuth2 authentication will explicitely ask for the
openid
scope.
2.3.2 - 2019-06-11
This is a patch version release with a security improvement.
Security vulnerability
-
Security improvement: On Linux and Android, starting a process with
Process.run
,Process.runSync
, orProcess.start
would first search the current directory before searchingPATH
(Issue 37101). This behavior effectively put the current working directory in the front ofPATH
, even if it wasn't in thePATH
. This release changes that behavior to only searching the directories in thePATH
environment variable. Operating systems other than Linux and Android didn't have this behavior and aren't affected by this vulnerability.This vulnerability could result in execution of untrusted code if a command without a slash in its name was run inside an untrusted directory containing an executable file with that name:
Process.run("ls", workingDirectory: "/untrusted/directory")
This would attempt to run
/untrusted/directory/ls
if it existed, even though it is not in thePATH
. It was always safe to instead use an absolute path or a path containing a slash.This vulnerability was introduced in Dart 2.0.0.
2.3.1 - 2019-05-21
This is a patch version release with bug fixes.
Tools
dart2js
- Fixed a bug that caused the compiler to crash when it compiled UI-as-code features within fields (Issue 36864).
2.3.0 - 2019-05-08
The focus in this release is on the new "UI-as-code" language features which make collections more expressive and declarative.
Language
Flutter is growing rapidly, which means many Dart users are building UI in code out of big deeply-nested expressions. Our goal with 2.3.0 was to make that kind of code easier to write and maintain. Collection literals are a large component, so we focused on three features to make collections more powerful. We'll use list literals in the examples below, but these features also work in map and set literals.
Spread
Placing ...
before an expression inside a collection literal unpacks the
result of the expression and inserts its elements directly inside the new
collection. Where before you had to write something like this:
CupertinoPageScaffold(
child: ListView(children: [
Tab2Header()
]..addAll(buildTab2Conversation())
..add(buildFooter())),
);
Now you can write this:
CupertinoPageScaffold(
child: ListView(children: [
Tab2Header(),
...buildTab2Conversation(),
buildFooter()
]),
);
If you know the expression might evaluate to null and you want to treat that as
equivalent to zero elements, you can use the null-aware spread ...?
.
Collection if
Sometimes you might want to include one or more elements in a collection only
under certain conditions. If you're lucky, you can use a ?:
operator to
selectively swap out a single element, but if you want to exchange more than one
or omit elements, you are forced to write imperative code like this:
Widget build(BuildContext context) {
var children = [
IconButton(icon: Icon(Icons.menu)),
Expanded(child: title)
];
if (isAndroid) {
children.add(IconButton(icon: Icon(Icons.search)));
}
return Row(children: children);
}
We now allow if
inside collection literals to conditionally omit or (with
else
) swap out an element:
Widget build(BuildContext context) {
return Row(
children: [
IconButton(icon: Icon(Icons.menu)),
Expanded(child: title),
if (isAndroid)
IconButton(icon: Icon(Icons.search)),
],
);
}
Unlike the existing ?:
operator, a collection if
can be composed with
spreads to conditionally include or omit multiple items:
Widget build(BuildContext context) {
return Row(
children: [
IconButton(icon: Icon(Icons.menu)),
if (isAndroid) ...[
Expanded(child: title),
IconButton(icon: Icon(Icons.search)),
]
],
);
}
Collection for
In many cases, the higher-order methods on Iterable give you a declarative way to modify a collection in the context of a single expression. But some operations, especially involving both transforming and filtering, can be cumbersome to express in a functional style.
To solve this problem, you can use for
inside a collection literal. Each
iteration of the loop produces an element which is then inserted in the
resulting collection. Consider the following code:
var command = [
engineDartPath,
frontendServer,
...fileSystemRoots.map((root) => "--filesystem-root=$root"),
...entryPoints
.where((entryPoint) => fileExists("lib/$entryPoint.json"))
.map((entryPoint) => "lib/$entryPoint"),
mainPath
];
With a collection for
, the code becomes simpler:
var command = [
engineDartPath,
frontendServer,
for (var root in fileSystemRoots) "--filesystem-root=$root",
for (var entryPoint in entryPoints)
if (fileExists("lib/$entryPoint.json")) "lib/$entryPoint",
mainPath
];
As you can see, all three of these features can be freely composed. For full details of the changes, see the official proposal.
Note: These features are not currently supported in const collection
literals. In a future release, we intend to relax this restriction and allow
spread and collection if
inside const collections.
Core library changes
dart:isolate
- Added
debugName
property toIsolate
. - Added
debugName
optional parameter toIsolate.spawn
andIsolate.spawnUri
.
dart:core
- RegExp patterns can now use lookbehind assertions.
- RegExp patterns can now use named capture groups and named backreferences. Currently, named group matches can only be retrieved in Dart either by the implicit index of the named group or by downcasting the returned Match object to the type RegExpMatch. The RegExpMatch interface contains methods for retrieving the available group names and retrieving a match by group name.
Dart VM
-
The VM service now requires an authentication code by default. This behavior can be disabled by providing the
--disable-service-auth-codes
flag. -
Support for deprecated flags '-c' and '--checked' has been removed.
Dart for the Web
dart2js
A binary format was added to dump-info. The old JSON format is still available and provided by default, but we are starting to deprecate it. The new binary format is more compact and cheaper to generate. On some large apps we tested, it was 4x faster to serialize and used 6x less memory.
To use the binary format today, use --dump-info=binary
, instead of
--dump-info
.
What to expect next?
-
The visualizer tool will not be updated to support the new binary format, but you can find several command-line tools at
package:dart2js_info
that provide similar features to those in the visualizer. -
The command-line tools in
package:dart2js_info
also work with the old JSON format, so you can start using them even before you enable the new format. -
In a future release
--dump-info
will default to--dump-info=binary
. At that point, there will be an option to fallback to the JSON format, but the visualizer tool will be deprecated. -
A release after that, the JSON format will no longer be available from dart2js, but may be available from a command-line tool in
package:dart2js_info
.
Tools
dartfmt
- Tweak set literal formatting to follow other collection literals.
- Add support for "UI as code" features.
- Properly format trailing commas in assertions.
- Improve indentation of adjacent strings in argument lists.
Linter
The Linter was updated to 0.1.86
, which includes the following changes:
- Added the following lints:
prefer_inlined_adds
,prefer_for_elements_to_map_fromIterable
,prefer_if_elements_to_conditional_expressions
,diagnostic_describe_all_properties
. - Updated
file_names
to skip prefixed-extension Dart files (.css.dart
,.g.dart
, etc.). - Fixed false positives in
unnecessary_parenthesis
.
Pub
- Added a CHANGELOG validator that complains if you
pub publish
without mentioning the current version. - Removed validation of library names when doing
pub publish
. - Added support for
pub global activate
ing package from a custom pub URL. - Added subcommand:
pub logout
. Logs you out of the current session.
Dart native
Initial support for compiling Dart apps to native machine code has been added.
Two new tools have been added to the bin
folder of the Dart SDK:
-
dart2aot
: AOT (ahead-of-time) compiles a Dart program to native machine code. The tool is supported on Windows, macOS, and Linux. -
dartaotruntime
: A small runtime used for executing an AOT compiled program.
2.2.0 - 2019-02-26
Language
Sets now have a literal syntax like lists and maps do:
var set = {1, 2, 3};
Using curly braces makes empty sets ambiguous with maps:
var collection = {}; // Empty set or map?
To avoid breaking existing code, an ambiguous literal is treated as a map. To create an empty set, you can rely on either a surrounding context type or an explicit type argument:
// Variable type forces this to be a set:
Set<int> set = {};
// A single type argument means this must be a set:
var set2 = <int>{};
Set literals are released on all platforms. The set-literals
experiment flag
has been disabled.
Tools
Analyzer
-
The
DEPRECATED_MEMBER_USE
hint was split into two hints:DEPRECATED_MEMBER_USE
reports on usage of@deprecated
members declared in a different package.DEPRECATED_MEMBER_USE_FROM_SAME_PACKAGE
reports on usage of@deprecated
members declared in the same package.
Linter
Upgraded the linter to 0.1.82
which adds the following improvements:
- Added
provide_deprecation_message
, anduse_full_hex_values_for_flutter_colors
,prefer_null_aware_operators
. - Fixed
prefer_const_declarations
set literal false-positives. - Updated
prefer_collection_literals
to support set literals. - Updated
unnecessary_parenthesis
play nicer with cascades. - Removed deprecated lints from the "all options" sample.
- Stopped registering "default lints".
- Fixed
hash_and_equals
to respecthashCode
fields.
Other libraries
package:kernel
-
Breaking change: The
klass
getter on theInstanceConstant
class in the Kernel AST API has been renamed toclassNode
for consistency. -
Breaking change: Updated
Link
implementation to utilize true symbolic links instead of junctions on Windows. Existing junctions will continue to work with the newLink
implementation, but all new links will create symbolic links.To create a symbolic link, Dart must be run with administrative privileges or Developer Mode must be enabled, otherwise a
FileSystemException
will be raised with errno set toERROR_PRIVILEGE_NOT_HELD
(Issue 33966).
2.1.1 - 2019-02-18
This is a patch version release. Again, the team's focus was mostly on improving performance and stability after the large changes in Dart 2.0.0. In particular, dart2js now always uses the "fast startup" emitter and the old emitter has been removed.
There are a couple of very minor breaking changes:
-
In
dart:io
, adding to a closedIOSink
now throws aStateError
. -
On the Dart VM, a soundness hole when using
dart:mirrors
to reflectively invoke a method in an incorrect way that violates its static types has been fixed (Issue 35611).
Language
This release has no language changes.
Core library
dart:core
- Made
DateTime.parse()
also recognize,
as a valid decimal separator when parsing from a string (Issue 35576).
dart:html
-
Added methods
Element.removeAttribute
,Element.removeAttributeNS
,Element.hasAttribute
andElement.hasAttributeNS
. (Issue 35655). -
Improved dart2js compilation of
element.attributes.remove(name)
to generateelement.removeAttribute(name)
, so that there is no performance reason to migrate to the above methods. -
Fixed a number of
dart:html
bugs:- Fixed HTML API's with callback typedef to correctly convert Dart functions to JS functions (Issue 35484).
- HttpStatus constants exposed in
dart:html
(Issue 34318). - Expose DomName
ondblclick
anddblclickEvent
for Angular analyzer. - Fixed
removeAll
onclasses
;elements
parameter should beIterable<Object>
to match Set'sremoveAll
notIterable<E>
(Issue 30278). - Fixed a number of methods on DataTransferItem, Entry, FileEntry and DirectoryEntry which previously returned NativeJavaScriptObject. This fixes handling drag/drop of files/directories (Issue 35510).
- Added ability to allow local file access from Chrome browser in ddb.
dart:io
- Breaking Change: Adding to a closed
IOSink
now throws aStateError
. - Added ability to get and set low level socket options.
Dart VM
In previous releases it was possible to violate static types using
dart:mirrors
. This code would run without any TypeErrors and print
"impossible" output:
import 'dart:mirrors';
class A {
void method(int v) {
if (v != null && v is! int) {
print("This should be impossible: expected null or int got ${v}");
}
}
}
void main() {
final obj = A();
reflect(obj).invoke(#method, ['not-an-number']);
}
This bug is fixed now. Only code that already violates static typing will break. See Issue 35611 for more details.
Dart for the Web
dart2js
-
The old "full emitter" back-end is removed and dart2js always uses the "fast startup" back-end. The generated fast startup code is optimized to load faster, even though it can be slightly larger. The
--fast-startup
and--no-fast-startup
are allowed but ignored. They will be removed in a future version. -
We fixed a bug in how deferred constructor calls were incorrectly not marked as deferred. The old behavior didn't cause breakages, but was imprecise and pushed more code to the main output unit.
-
A new deferred split algorithm implementation was added.
This implementation fixes a soundness bug and addresses performance issues of the previous implementation, because of that it can have a visible impact on apps. In particular:
-
We fixed a performance issue which was introduced when we migrated to the common front-end. On large apps, the fix can cut 2/3 of the time spent on this task.
-
We fixed a bug in how inferred types were categorized (Issue 35311). The old behavior was unsound and could produce broken programs. The fix may cause more code to be pulled into the main output unit.
This shows up frequently when returning deferred values from closures since the closure's inferred return type is the deferred type. For example, if you have:
() async { await deferred_prefix.loadLibrary(); return new deferred_prefix.Foo(); }
The closure's return type is
Future<Foo>
. The old implementation defersFoo
, and incorrectly makes the return typeFuture<dynamic>
. This may break in places where the correct type is expected.The new implementation will not defer
Foo
, and will place it in the main output unit. If your intent is to defer it, then you need to ensure the return type is not inferred to beFoo
. For example, you can do so by changing the code to a named closure with a declared type, or by ensuring that the return expression has the type you want, like:() async { await deferred_prefix.loadLibrary(); return new deferred_prefix.Foo() as dynamic; }
Because the new implementation might require you to inspect and fix your app, we exposed two temporary flags:
-
The
--report-invalid-deferred-types
causes dart2js to run both the old and new algorithms and report any cases where an invalid type was detected. -
The
--new-deferred-split
flag enables this new algorithm.
-
-
The
--categories=*
flag is being replaced.--categories=all
was only used for testing and it is no longer supported.--categories=Server
continues to work at this time but it is deprecated, please use--server-mode
instead. -
The
--library-root
flag was replaced by--libraries-spec
. This flag is rarely used by developers invoking dart2js directly. It's important for integrating dart2js with build systems. See--help
for more details on the new flag.
Tools
Analyzer
-
Support for
declarations-casts
has been removed and theimplicit-casts
option now has the combined semantics of both options. This means that users that disableimplicit-casts
might now see errors that were not previously being reported. -
New hints added:
NON_CONST_CALL_TO_LITERAL_CONSTRUCTOR
andNON_CONST_CALL_TO_LITERAL_CONSTRUCTOR_USING_NEW
inform you when a@literal
const constructor is called in a non-const context (or withnew
).INVALID_LITERAL_ANNOTATION
reports when something other than a const constructor is annotated with@literal
.SUBTYPE_OF_SEALED_CLASS
reports when any class or mixin subclasses (extends, implements, mixes in, or constrains to) a@sealed
class, and the two are declared in different packages.MIXIN_ON_SEALED_CLASS
reports when a@sealed
class is used as a superclass constraint of a mixin.
dartdoc
Default styles now work much better on mobile. Simple browsing and searching of API docs now work in many cases.
Upgraded the linter to 0.1.78
which adds the following improvements:
- Added
prefer_final_in_for_each
,unnecessary_await_in_return
,use_function_type_syntax_for_parameters
,avoid_returning_null_for_future
, andavoid_shadowing_type_parameters
. - Updated
invariant_booleans
status to experimental. - Fixed
type_annotate_public_apis
false positives on local functions. - Fixed
avoid_shadowing_type_parameters
to report shadowed type parameters in generic typedefs. - Fixed
use_setters_to_change_properties
to not wrongly lint overriding methods. - Fixed
cascade_invocations
to not lint awaited targets. - Fixed
prefer_conditional_assignment
false positives. - Fixed
join_return_with_assignment
false positives. - Fixed
cascade_invocations
false positives. - Deprecated
prefer_bool_in_asserts
as it is redundant in Dart 2.
2.1.0 - 2018-11-15
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 usesmixin
: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 likefontSize
: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 exportsFuture
andStream
. You no longer need to importdart:async
to use those very common types.
Language
-
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 usesuper
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 explicitnew
: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
incore.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.
Core libraries
dart:async
- Fixed a bug where calling
stream.take(0).drain(value)
would not correctly forward thevalue
through the returnedFuture
. - Added a
StreamTransformer.fromBind
constructor. - Updated
Stream.fromIterable
to send a done event after the error when the iterator'smoveNext
throws, and handle if thecurrent
getter throws (issue 33431).
dart:core
- Added
HashMap.fromEntries
andLinkedHashmap.fromEntries
constructors. - Added
ArgumentError.checkNotNull
utility method. - Made
Uri
parsing more permissive about[
and]
occurring in the path, query or fragment, and#
occurring in fragment. - Exported
Future
andStream
fromdart:core
. - Added operators
&
,|
and^
tobool
. - Added missing methods to
UnmodifiableMapMixin
. Some maps intended to be unmodifiable incorrectly allowed new methods added in Dart 2 to succeed. - Deprecated the
provisional
annotation and theProvisional
annotation class. These should have been removed before releasing Dart 2.0, and they have no effect.
dart:html
Fixed 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.instance
DedicatedWorkerGlobalScope.instance
ServiceWorkerGlobalScope.instance
WorkerGlobalScope.instance
dart:io
- Added new HTTP status codes.
Dart for the Web
dart2js
-
(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 rundart2js -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
.
Tool Changes
dartfmt
- Addressed several dartfmt issues when used with the new CFE parser.
Linter
Bumped the linter to 0.1.70
which includes the following new lints:
avoid_returning_null_for_void
sort_pub_dependencies
prefer_mixin
avoid_implementing_value_types
flutter_style_todos
avoid_void_async
prefer_void_to_null
and improvements:
- Fixed NPE in
prefer_iterable_whereType
. - Improved message display for
await_only_futures
- Performance improvements for
null_closures
- Mixin support
- Updated
sort_constructors_first
to apply to all members. - Updated
unnecessary_this
to work on field initializers. - Updated
unawaited_futures
to ignore assignments within cascades. - Improved handling of constant expressions with generic type params.
- NPE fix for
invariant_booleans
. - Improved docs for
unawaited_futures
. - Updated
unawaited_futures
to check cascades. - Relaxed
void_checks
(allowingT Function()
to be assigned tovoid Function()
). - Fixed false positives in
lines_longer_than_80_chars
.
Pub
- Renamed the
--checked
flag topub run
to--enable-asserts
. - Pub will no longer delete directories named "packages".
- The
--packages-dir
flag is now ignored.
2.0.0 - 2018-08-07
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 firstawait
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
tolowerCamelCase
. -
(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.
Language
-
"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 firstawait
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 likedynamic
, andObject
. 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 typeFuture<Object>
does not report an error. -
return exp;
whereexp
has typevoid
in an async function is now an error unless the return type of the function isvoid
ordynamic
. -
Mixed return statements of the form
return;
andreturn exp;
are now allowed whenexp
has typevoid
. -
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).
Core libraries
-
Replaced
UPPER_CASE
constant names withlowerCamelCase
. For example,HTML_ESCAPE
is nowhtmlEscape
. -
The Web libraries were re-generated using Chrome 63 WebIDLs (details).
dart:async
Stream
:- Added
cast
andcastFrom
. - Changed
firstWhere
,lastWhere
, andsingleWhere
to returnFuture<T>
and added an optionalT orElse()
callback.
- Added
StreamTransformer
: addedcast
andcastFrom
.StreamTransformerBase
: new class.Timer
: addedtick
property.Zone
- changed to be strong-mode clean. This required some breaking API changes. See https://goo.gl/y9mW2x for more information.
- Added
bindBinaryCallbackGuarded
,bindCallbackGuarded
, andbindUnaryCallbackGuarded
. - Renamed
Zone.ROOT
toZone.root
.
- Removed the deprecated
defaultValue
parameter onStream.firstWhere
andStream.lastWhere
. - Changed an internal lazily-allocated reusable "null future" to always belong to the root zone. This avoids race conditions where the first access to the future determined which zone it would belong to. The zone is only used for scheduling the callback of listeners, the listeners themselves will run in the correct zone in any case. Issue #32556.
dart:cli
- New "provisional" library for CLI-specific features.
waitFor
: function that suspends a stack to wait for aFuture
to complete.
dart:collection
MapBase
: addedmapToString
.LinkedHashMap
no longer implementsHashMap
LinkedHashSet
no longer implementsHashSet
.- Added
of
constructor toQueue
,ListQueue
,DoubleLinkedQueue
,HashSet
,LinkedHashSet
,SplayTreeSet
,Map
,HashMap
,LinkedHashMap
,SplayTreeMap
. - Removed
Maps
class. ExtendMapBase
or mix inMapMixin
instead to provide map method implementations for a class. - Removed experimental
Document
methodgetCSSCanvasContext
and propertysupportsCssCanvasContext
. - Removed obsolete
Element
propertyxtag
no longer supported in browsers. - Exposed
ServiceWorker
class. - Added constructor to
MessageChannel
andMessagePort
addEventListener
automatically callsstart
method to receive queued messages.
dart:convert
Base64Codec.decode
return type is nowUint8List
.JsonUnsupportedObjectError
: addedpartialResult
propertyLineSplitter
now implementsStreamTransformer<String, String>
instead ofConverter
. It retainsConverter
methodsconvert
andstartChunkedConversion
.Utf8Decoder
when compiled with dart2js uses the browser'sTextDecoder
in some common cases for faster decoding.- Renamed
ASCII
,BASE64
,BASE64URI
,JSON
,LATIN1
andUTF8
toascii
,base64
,base64Uri
,json
,latin1
andutf8
. - Renamed the
HtmlEscapeMode
constantsUNKNOWN
,ATTRIBUTE
,SQ_ATTRIBUTE
andELEMENT
tounknown
,attribute
,sqAttribute
andelements
. - Added
jsonEncode
,jsonDecode
,base64Encode
,base64UrlEncode
andbase64Decode
top-level functions. - Changed return type of
encode
onAsciiCodec
andLatin1Codec
, andconvert
onAsciiEncoder
,Latin1Encoder
, toUint8List
. - Allow
utf8.decoder.fuse(json.decoder)
to ignore leading Unicode BOM.
dart:core
BigInt
class added to support integers greater than 64-bits.- Deprecated the
proxy
annotation. - Added
Provisional
class andprovisional
field. - Added
pragma
annotation. RegExp
added staticescape
function.- The
Uri
class now correctly handles paths while running on Node.js on Windows. - Core collection changes:
Iterable
added memberscast
,castFrom
,followedBy
andwhereType
.Iterable.singleWhere
addedorElse
parameter.List
added+
operator,first
andlast
setters, andindexWhere
andlastIndexWhere
methods, and staticcopyRange
andwriteIterable
methods.Map
addedfromEntries
constructor.Map
addedaddEntries
,cast
,entries
,map
,removeWhere
,update
andupdateAll
members.MapEntry
: new class used byMap.entries
.- Note: if a class extends
IterableBase
,ListBase
,SetBase
orMapBase
(or uses the corresponding mixins) fromdart:collection
, the new members are implemented automatically. - Added
of
constructor toList
,Set
,Map
.
- Renamed
double.INFINITY
,double.NEGATIVE_INFINITY
,double.NAN
,double.MAX_FINITE
anddouble.MIN_POSITIVE
todouble.infinity
,double.negativeInfinity
,double.nan
,double.maxFinite
anddouble.minPositive
. - Renamed the following constants in
DateTime
to lower case:MONDAY
throughSUNDAY
,DAYS_PER_WEEK
(asdaysPerWeek
),JANUARY
throughDECEMBER
andMONTHS_PER_YEAR
(asmonthsPerYear
). - Renamed the following constants in
Duration
to lower case:MICROSECONDS_PER_MILLISECOND
tomicrosecondsPerMillisecond
,MILLISECONDS_PER_SECOND
tomillisecondsPerSecond
,SECONDS_PER_MINUTE
tosecondsPerMinute
,MINUTES_PER_HOUR
tominutesPerHour
,HOURS_PER_DAY
tohoursPerDay
,MICROSECONDS_PER_SECOND
tomicrosecondsPerSecond
,MICROSECONDS_PER_MINUTE
tomicrosecondsPerMinute
,MICROSECONDS_PER_HOUR
tomicrosecondsPerHour
,MICROSECONDS_PER_DAY
tomicrosecondsPerDay
,MILLISECONDS_PER_MINUTE
tomillisecondsPerMinute
,MILLISECONDS_PER_HOUR
tomillisecondsPerHour
,MILLISECONDS_PER_DAY
tomillisecondsPerDay
,SECONDS_PER_HOUR
tosecondsPerHour
,SECONDS_PER_DAY
tosecondsPerDay
,MINUTES_PER_DAY
tominutesPerDay
, andZERO
tozero
. - Added
typeArguments
toInvocation
class. - Added constructors to invocation class that allows creation of
Invocation
objects directly, without going throughnoSuchMethod
. - Added
unaryMinus
andempty
constant symbols on theSymbol
class. - Changed return type of
UriData.dataAsBytes
toUint8List
. - Added
tryParse
static method toint
,double
,num
,BigInt
,Uri
andDateTime
. - Deprecated
onError
parameter onint.parse
,double.parse
andnum.parse
. - Deprecated the
NoSuchMethodError
constructor. int.parse
on the VM no longer accepts unsigned hexadecimal numbers greater than or equal to2**63
when not prefixed by0x
. (SDK issue 32858)
dart:developer
Flow
class added.Timeline.startSync
andTimeline.timeSync
now accept an optional parameterflow
of typeFlow
. Theflow
parameter is used to generate flow timeline events that are enclosed by the slice described byTimeline.{start,finish}Sync
andTimeline.timeSync
.
dart:html
- Removed deprecated
query
andqueryAll
. UsequerySelector
andquerySelectorAll
.
dart:io
HttpStatus
addedUPGRADE_REQUIRED
.IOOverrides
andHttpOverrides
added to aid in writing tests that wish to mock variosdart: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.- Unified backends for
SecureSocket
,SecurityContext
, andX509Certificate
to be consistent across all platforms. AllSecureSocket
,SecurityContext
, andX509Certificate
properties and methods are now supported on iOS and OSX. SecurityContext.alpnSupported
deprecated as ALPN is now supported on all platforms.SecurityContext
: addedwithTrustedRoots
named optional parameter constructor, which defaults to false.- Added a
timeout
parameter toSocket.connect
,RawSocket.connect
,SecureSocket.connect
andRawSecureSocket.connect
. If a connection attempt takes longer than the duration specified intimeout
, aSocketException
will be thrown. Note: if the duration specified intimeout
is greater than the OS level timeout, a timeout may occur sooner than specified intimeout
. Stdin.hasTerminal
added, which is true if stdin is attached to a terminal.WebSocket
added staticuserAgent
property.RandomAccessFile.close
returnsFuture<void>
- Added
IOOverrides.socketConnect
. - Added Dart-styled constants to
ZLibOptions
,FileMode
,FileLock
,FileSystemEntityType
,FileSystemEvent
,ProcessStartMode
,ProcessSignal
,InternetAddressType
,InternetAddress
,SocketDirection
,SocketOption
,RawSocketEvent
, andStdioType
, and deprecated the oldSCREAMING_CAPS
constants. - Added the Dart-styled top-level constants
zlib
,gzip
, andsystemEncoding
, and deprecated the oldSCREAMING_CAPS
top-level constants. - Removed the top-level
FileMode
constantsREAD
,WRITE
,APPEND
,WRITE_ONLY
, andWRITE_ONLY_APPEND
. Please use e.g.FileMode.read
instead. - Added
X509Certificate.der
,X509Certificate.pem
, andX509Certificate.sha1
. - Added
FileSystemEntity.fromRawPath
constructor to allow for the creation ofFileSystemEntity
usingUint8List
buffers. - Dart-styled constants have been added for
HttpStatus
,HttpHeaders
,ContentType
,HttpClient
,WebSocketStatus
,CompressionOptions
, andWebSocket
. TheSCREAMING_CAPS
constants are marked deprecated. Note thatHttpStatus.CONTINUE
is nowHttpStatus.continue_
, and that e.g.HttpHeaders.FIELD_NAME
is nowHttpHeaders.fieldNameHeader
. - Deprecated
Platform.packageRoot
, which is only used forpackages/
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. - Adds
HttpClient.connectionTimeout
. - Adds
{Socket,RawSocket,SecureSocket}.startConnect
. These return aConnectionTask
, which can be used to cancel an in-flight connection attempt.
dart:isolate
- Make
Isolate.spawn
take a type parameter representing the argument type of the provided function. This allows functions with arguments types other thanObject
in strong mode. - Rename
IMMEDIATE
andBEFORE_NEXT_EVENT
onIsolate
toimmediate
andbeforeNextEvent
. - Deprecated
Isolate.packageRoot
, which is only used forpackages/
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. - Deprecated
packageRoot
parameter inIsolate.spawnUri
, which is was previously used only forpackages/
directory resolution. That style of resolution is no longer supported in Dart 2.
dart.math
- Renamed
E
,LN10
,LN
,LOG2E
,LOG10E
,PI
,SQRT1_2
andSQRT2
toe
,ln10
,ln
,log2e
,log10e
,pi
,sqrt1_2
andsqrt2
.
dart.mirrors
- Added
IsolateMirror.loadUri
, which allows dynamically loading additional code. - Marked
MirrorsUsed
as deprecated. TheMirrorsUsed
annotation was only used to inform the dart2js compiler about how mirrors were used, but dart2js no longer supports the mirrors library altogether.
dart:typed_data
- Added
Unmodifiable
view classes over allList
types. - Renamed
BYTES_PER_ELEMENT
tobytesPerElement
on all typed data lists. - Renamed constants
XXXX
throughWWWW
onFloat32x4
andInt32x4
to lower-casexxxx
throughwwww
. - Renamed
Endinanness
toEndian
and its constants fromBIG_ENDIAN
,LITTLE_ENDIAN
andHOST_ENDIAN
tolittle
,big
andhost
.
Dart VM
-
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/master/docs/language/informal/int64.md for details. -
The Dart VM no longer attempts to perform
packages/
directory resolution (for loading scripts, and inIsolate.resolveUri
). Users relying onpackages/
directories should switch to.packages
files.
Dart for the Web
-
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.
Dart Dev Compiler (DDC)
-
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 onIterable<T>
,Map<T>
,Future<T>
, andStream<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
-
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 fromdart:html
or JS-interop. -
dart2js no longer supports the
--package-root
flag. This flag was deprecated in favor of--packages
long ago.
Tool Changes
Analyzer
-
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 atest/
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 ofpackages
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 forstrong-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.
dartfmt
-
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 unneedednew
andconst
keywords, and change:
to=
before named parameter default values. -
Change formatting rules around static methods to uniformly format code with and without
new
andconst
. -
Format expressions inside string interpolation.
Pub
-
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
, andpub serve
. Use the new build system 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 as2.0.0-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 thePUB_ALLOW_PRERELEASE_SDK
environment variable tofalse
. -
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 topub deps
command. This will list all available executables that can be run withpub run
. -
The Flutter
sdk
source will now look for packages influtter/bin/cache/pkg/
as well asflutter/packages/
. In particular, this means that packages can depend on thesky_engine
package from thesdk
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.
1.24.3 - 2017-12-14
- Fix for constructing a new SecurityContext that contains the built-in certificate authority roots (issue 24693).
Core library changes
dart:io
- Unified backends for
SecureSocket
,SecurityContext
, andX509Certificate
to be consistent across all platforms. AllSecureSocket
,SecurityContext
, andX509Certificate
properties and methods are now supported on iOS and OSX.
- Unified backends for
1.24.2 - 2017-06-22
- Fixes for debugging in Dartium.
- Fix DevConsole crash with JS (issue 29873).
- Fix debugging in WebStorm, NULL returned for JS objects (issue 29854).
1.24.1 - 2017-06-14
- Bug fixes for dartdevc support in
pub serve
.- Fixed module config invalidation logic so modules are properly recalculated when package layout changes.
- Fixed exception when handling require.js errors that aren't script load errors.
- Fixed an issue where requesting the bootstrap.js file before the dart.js file would result in a 404.
- Fixed a Safari issue during bootstrapping (note that Safari is still not officially supported but does work for trivial examples).
- Fix for a Dartium issue where there was no sound in checked mode (issue 29810).
1.24.0 - 2017-06-12
Language
-
During a dynamic type check,
void
is not required to benull
anymore. In practice, this makes overridingvoid
functions with non-void
functions safer. -
During static analysis, a function or setter declared using
=>
with return typevoid
now allows the returned expression to have any type. For example, assuming the declarationint x;
, it is now type correct to havevoid f() => ++x;
. -
A new function-type syntax has been added to the language. Warning: In Dart 1.24, this feature is incomplete, and not stable in the Analyzer.
Intuitively, the type of a function can be constructed by textually replacing the function's name with
Function
in its declaration. For instance, the type ofvoid foo() {}
would bevoid Function()
. The new syntax may be used wherever a type can be written. It is thus now possible to declare fields containing functions without needing to write typedefs:void Function() x;
. The new function type has one restriction: it may not contain the old-style function-type syntax for its parameters. The following is thus illegal:void Function(int f())
.typedefs
have been updated to support this new syntax.Examples:
typedef F = void Function(); // F is the name for a `void` callback. int Function(int) f; // A field `f` that contains an int->int function. class A<T> { // The parameter `callback` is a function that takes a `T` and returns // `void`. void forEach(void Function(T) callback); } // The new function type supports generic arguments. typedef Invoker = T Function<T>(T Function() callback);
Core library changes
-
dart:async
,dart:core
,dart:io
- Adding to a closed sink, including
IOSink
, is no longer not allowed. In 1.24, violations are only reported (on stdout or stderr), but a future version of the Dart SDK will change this to throwing aStateError
.
- Adding to a closed sink, including
-
dart:convert
- BREAKING Removed the deprecated
ChunkedConverter
class. - JSON maps are now typed as
Map<String, dynamic>
instead ofMap<dynamic, dynamic>
. A JSON-map is not aHashMap
orLinkedHashMap
anymore (but just aMap
).
- BREAKING Removed the deprecated
-
dart:io
- Added
Platform.localeName
, needed for accessing the locale on platforms that don't store it in an environment variable. - Added
ProcessInfo.currentRss
andProcessInfo.maxRss
for inspecting the Dart VM process current and peak resident set size. - Added
RawSynchronousSocket
, a basic synchronous socket implementation.
- Added
-
dart:
web APIs have been updated to align with Chrome v50. This change includes a large number of changes, many of which are breaking. In some cases, new class names may conflict with names that exist in existing code. -
dart:html
-
REMOVED classes:
Bluetooth
,BluetoothDevice
,BluetoothGattCharacteristic
,BluetoothGattRemoteServer
,BluetoothGattService
,BluetoothUuid
,CrossOriginConnectEvent
,DefaultSessionStartEvent
,DomSettableTokenList
,MediaKeyError
,PeriodicSyncEvent
,PluginPlaceholderElement
,ReadableStream
,StashedMessagePort
,SyncRegistration
-
REMOVED members:
texImage2DCanvas
was removed fromRenderingContext
.endClip
andstartClip
were removed fromAnimation
.after
andbefore
were removed fromCharacterData
,ChildNode
andElement
.keyLocation
was removed fromKeyboardEvent
. Uselocation
instead.generateKeyRequest
,keyAddedEvent
,keyErrorEvent
,keyMessageEvent
,mediaGroup
,needKeyEvent
,onKeyAdded
,onKeyError
,onKeyMessage
, andonNeedKey
were removed fromMediaElement
.getStorageUpdates
was removed fromNavigator
status
was removed fromPermissionStatus
getAvailability
was removed fromPreElement
-
Other behavior changes:
- URLs returned in CSS or html are formatted with quoted string.
Like
url("http://google.com")
instead ofurl(http://google.com)
. - Event timestamp property type changed from
int
tonum
. - Chrome introduced slight layout changes of UI objects.
In addition many height/width dimensions are returned in subpixel values
(
num
instead of whole numbers). setRangeText
with aselectionMode
value of 'invalid' is no longer valid. Only "select", "start", "end", "preserve" are allowed.
- URLs returned in CSS or html are formatted with quoted string.
Like
-
-
dart:svg
- A large number of additions and removals. Review your use of
dart:svg
carefully.
- A large number of additions and removals. Review your use of
-
dart:web_audio
- new method on
AudioContext
–createIirFilter
returns a new classIirFilterNode
.
- new method on
-
dart:web_gl
-
new classes:
CompressedTextureAstc
,ExtColorBufferFloat
,ExtDisjointTimerQuery
, andTimerQueryExt
. -
ExtFragDepth
added:readPixels2
andtexImage2D2
.
-
Strong Mode
-
Removed ad hoc
Future.then
inference in favor of usingFutureOr
. Prior to addingFutureOr
to the language, the analyzer implented an ad hoc type inference forFuture.then
(and overrides) treating it as if the onValue callback was typed to returnFutureOr
for the purposes of inference. This ad hoc inference has been removed now thatFutureOr
has been added.Packages that implement
Future
must either type theonValue
parameter to.then
as returningFutureOr<T>
, or else must leave the type of the parameter entirely to allow inference to fill in the type. -
During static analysis, a function or setter declared using
=>
with return typevoid
now allows the returned expression to have any type.
Tool Changes
-
Dartium
Dartium is now based on Chrome v50. See Core library changes above for details on the changed APIs.
-
Pub
-
pub build
andpub serve
-
Added support for the Dart Development Compiler.
Unlike dart2js, this new compiler is modular, which allows pub to do incremental re-builds for
pub serve
, and potentiallypub build
in the future.In practice what that means is you can edit your Dart files, refresh in Chrome (or other supported browsers), and see your edits almost immediately. This is because pub is only recompiling your package, not all packages that you depend on.
There is one caveat with the new compiler, which is that your package and your dependencies must all be strong mode clean. If you are getting an error compiling one of your dependencies, you will need to file bugs or send pull requests to get them strong mode clean.
There are two ways of opting into the new compiler:
-
Use the new
--web-compiler
flag, which supportsdartdevc
,dart2js
ornone
as options. This is the easiest way to try things out without changing the default. -
Add config to your pubspec. There is a new
web
key which supports a single key calledcompiler
. This is a map from mode names to compiler to use. For example, to default to dartdevc in debug mode you can add the following to your pubspec:web: compiler: debug: dartdevc
You can also use the new compiler to run your tests in Chrome much more quickly than you can with dart2js. In order to do that, run
pub serve test --web-compiler=dartdevc
, and then runpub run test -p chrome --pub-serve=8080
. -
-
The
--no-dart2js
flag has been deprecated in favor of--web-compiler=none
. -
pub build
will use a failing exit code if there are errors in any transformer.
-
-
pub publish
-
Added support for the UNLICENSE file.
-
Packages that depend on the Flutter SDK may be published.
-
-
pub get
andpub upgrade
- Don't dump a stack trace when a network error occurs while fetching packages.
-
-
dartfmt
- Preserve type parameters in new generic function typedef syntax.
- Add self-test validation to ensure formatter bugs do not cause user code to be lost.
Infrastructure changes
- As of this release, we'll show a warning when using the MIPS architecture. Unless we learn about any critical use of Dart on MIPS in the meantime, we're planning to deprecate support for MIPS starting with the next stable release.
1.23.0 - 2017-04-21
Strong Mode
- Breaking change - it is now a strong mode error if a mixin causes a name conflict between two private members (field/getter/setter/method) from a different library. (SDK issue 28809).
lib1.dart:
class A {
int _x;
}
class B {
int _x;
}
lib2.dart:
import 'lib1.dart';
class C extends A with B {}
error • The private name _x, defined by B, conflicts with the same name defined by A at tmp/lib2.dart:3:24 • private_collision_in_mixin_application
-
Breaking change - strong mode will prefer the expected type to infer generic types, functions, and methods (SDK issue 27586).
main() { List<Object> foo = /*infers: <Object>*/['hello', 'world']; var bar = /*infers: <String>*/['hello', 'world']; }
-
Strong mode inference error messages are improved (SDK issue 29108).
import 'dart:math'; test(Iterable/* fix is to add <num> here */ values) { num n = values.fold(values.first as num, max); }
Now produces the error on the generic function "max":
Couldn't infer type parameter 'T'. Tried to infer 'dynamic' for 'T' which doesn't work: Function type declared as '<T extends num>(T, T) → T' used where '(num, dynamic) → num' is required. Consider passing explicit type argument(s) to the generic.
-
Strong mode supports overriding fields,
@virtual
is no longer required (SDK issue 28120).class C { int x = 42; } class D extends C { get x { print("x got called"); return super.x; } } main() { print(new D().x); }
-
Strong mode down cast composite warnings are no longer issued by default. (SDK issue 28588).
void test() {
List untyped = [];
List<int> typed = untyped; // No down cast composite warning
}
To opt back into the warnings, add the following to the .analysis_options file for your project.
analyzer:
errors:
strong_mode_down_cast_composite: warning
Core library changes
dart:core
- Added
Uri.isScheme
function to check the scheme of a URI. Example:uri.isScheme("http")
. Ignores case when comparing. - Make
UriData.parse
validate its input better. If the data is base-64 encoded, the data is normalized wrt. alphabet and padding, and it contains invalid base-64 data, parsing fails. Also normalizes non-base-64 data.
- Added
dart:io
- Added functions
File.lastAccessed
,File.lastAccessedSync
,File.setLastModified
,File.setLastModifiedSync
,File.setLastAccessed
, andFile.setLastAccessedSync
. - Added
{Stdin,Stdout}.supportsAnsiEscapes
.
- Added functions
Dart VM
- Calls to
print()
andStdout.write*()
now correctly print unicode characters to the console on Windows. Calls toStdout.add*()
behave as before.
Tool changes
-
Analysis
dartanalyzer
now follows the same rules as the analysis server to find an analysis options file, stopping when an analysis options file is found:- Search up the directory hierarchy looking for an analysis options file.
- If analyzing a project referencing the Flutter
package, then use the
default Flutter analysis options
found in
package:flutter
. - If in a Bazel workspace, then use the analysis options in
package:dart.analysis_options/default.yaml
if it exists. - Use the default analysis options rules.
- In addition, specific to
dartanalyzer
:- an analysis options file can be specified on the command line via
--options
and that file will be used instead of searching for an analysis options file. - any analysis option specified on the command line
(e.g.
--strong
or--no-strong
) takes precedence over any corresponding value specified in the analysis options file.
- an analysis options file can be specified on the command line via
-
Dartium, dart2js, and DDC
- Imports to
dart:io
are allowed, but the imported library is not supported and will likely fail on most APIs at runtime. This change was made as a stopgap measure to make it easier to write libraries that share code between platforms (like packagehttp
). This might change again when configuration specific imports are supported.
- Imports to
-
Pub
- Now sends telemetry data to
pub.dartlang.org
to allow better understanding of why a particular package is being accessed. pub publish
- Warns if a package imports a package that's not a dependency from within
lib/
orbin/
, or a package that's not a dev dependency from withinbenchmark/
,example/
,test/
ortool/
. - No longer produces "UID too large" errors on OS X. All packages are now uploaded with the user and group names set to "pub".
- No longer fails with a stack overflow when uploading a package that uses Git submodules.
- Warns if a package imports a package that's not a dependency from within
pub get
andpub upgrade
- Produce more informative error messages if they're run directly in a package that uses Flutter.
- Properly unlock SDK and path dependencies if they have a new version that's also valid according to the user's pubspec.
- Now sends telemetry data to
-
dartfmt
- Support new generic function typedef syntax.
- Make the precedence of cascades more visible.
- Fix a couple of places where spurious newlines were inserted.
- Correctly report unchanged formatting when reading from stdin.
- Ensure space between
-
and--
. Code that does this is pathological, but it technically meant dartfmt could change the semantics of the code. - Preserve a blank line between enum cases.
- Other small formatting tweaks.
1.22.1 - 2017-02-22
Patch release, resolves two issues:
-
Dart VM crash: Issue 28072
-
Dart VM bug combining types, await, and deferred loading: Issue 28678
1.22.0 - 2017-02-14
Language
-
Breaking change: 'Generalized tear-offs' are no longer supported, and will cause errors. We updated the language spec and added warnings in 1.21, and are now taking the last step to fully de-support them. They were previously only supported in the VM, and there are almost no known uses of them in the wild.
-
The
assert()
statement has been expanded to support an optional secondmessage
argument (SDK issue 27342).The message is displayed if the assert fails. It can be any object, and it is accessible as
AssertionError.message
. It can be used to provide more user friendly exception outputs. As an example, the following assert:assert(configFile != null, "Tool config missing. Please see https://goo.gl/k8iAi for details.");
would produce the following exception output:
Unhandled exception: 'file:///Users/mit/tmp/tool/bin/main.dart': Failed assertion: line 9 pos 10: 'configFile != null': Tool config missing. Please see https://goo.gl/k8iAi for details. #0 _AssertionError._doThrowNew (dart:core-patch/errors_patch.dart:33) #1 _AssertionError._throwNew (dart:core-patch/errors_patch.dart:29) #2 main (file:///Users/mit/tmp/tool/bin/main.dart:9:10)
-
The
Null
type has been moved to the bottom of the type hierarchy. As such, it is considered a subtype of every other type. Thenull
literal was always treated as a bottom type. Now the named classNull
is too:const empty = <Null>[]; String concatenate(List<String> parts) => parts.join(); int sum(List<int> numbers) => numbers.fold(0, (sum, n) => sum + n); concatenate(empty); // OK. sum(empty); // OK.
-
Introduce
covariant
modifier on parameters. It indicates that the parameter (and the corresponding parameter in any method that overrides it) has looser override rules. In strong mode, these require a runtime type check to maintain soundness, but enable an architectural pattern that is useful in some code.It lets you specialize a family of classes together, like so:
abstract class Predator { void chaseAndEat(covariant Prey p); } abstract class Prey {} class Mouse extends Prey {} class Seal extends Prey {} class Cat extends Predator { void chaseAndEat(Mouse m) => ... } class Orca extends Predator { void chaseAndEat(Seal s) => ... }
This isn't statically safe, because you could do:
Predator predator = new Cat(); // Upcast. predator.chaseAndEat(new Seal()); // Cats can't eat seals!
To preserve soundness in strong mode, in the body of a method that uses a covariant override (here,
Cat.chaseAndEat()
), the compiler automatically inserts a check that the parameter is of the expected type. So the compiler gives you something like:class Cat extends Predator { void chaseAndEat(o) { var m = o as Mouse; ... } }
Spec mode allows this unsound behavior on all parameters, even though users rarely rely on it. Strong mode disallowed it initially. Now, strong mode lets you opt into this behavior in the places where you do want it by using this modifier. Outside of strong mode, the modifier is ignored.
-
Change instantiate-to-bounds rules for generic type parameters when running in strong mode. If you leave off the type parameters from a generic type, we need to decide what to fill them in with. Dart 1.0 says just use
dynamic
, but that isn't sound:class Abser<T extends num> { void absThis(T n) { n.abs(); } } var a = new Abser(); // Abser<dynamic>. a.absThis("not a num");
We want the body of
absThis()
to be able to safely assumen
is at least anum
-- that's why there's a constraint on T, after all. Implicitly usingdynamic
as the type parameter in this example breaks that.Instead, strong mode uses the bound. In the above example, it fills it in with
num
, and then the second line where a string is passed becomes a static error.However, there are some cases where it is hard to figure out what that default bound should be:
class RuhRoh<T extends Comparable<T>> {}
Strong mode's initial behavior sometimes produced surprising, unintended results. For 1.22, we take a simpler approach and then report an error if a good default type argument can't be found.
Core libraries
-
Define
FutureOr<T>
for code that works with either a future or an immediate value of some type. For example, say you do a lot of text manipulation, and you want a handy function to chain a bunch of them:typedef String StringSwizzler(String input); String swizzle(String input, List<StringSwizzler> swizzlers) { var result = input; for (var swizzler in swizzlers) { result = swizzler(result); } return result; }
This works fine:
main() { var result = swizzle("input", [ (s) => s.toUpperCase(), (s) => () => s * 2) ]); print(result); // "INPUTINPUT". }
Later, you realize you'd also like to support swizzlers that are asynchronous (maybe they look up synonyms for words online). You could make your API strictly asynchronous, but then users of simple synchronous swizzlers have to manually wrap the return value in a
Future.value()
. Ideally, yourswizzle()
function would be "polymorphic over asynchrony". It would allow both synchronous and asynchronous swizzlers. Becauseawait
accepts immediate values, it is easy to implement this dynamically:Future<String> swizzle(String input, List<StringSwizzler> swizzlers) async { var result = input; for (var swizzler in swizzlers) { result = await swizzler(result); } return result; } main() async { var result = swizzle("input", [ (s) => s.toUpperCase(), (s) => new Future.delayed(new Duration(milliseconds: 40), () => s * 2) ]); print(await result); }
What should the declared return type on StringSwizzler be? In the past, you had to use
dynamic
orObject
, but that doesn't tell the user much. Now, you can do:typedef FutureOr<String> StringSwizzler(String input);
Like the name implies,
FutureOr<String>
is a union type. It can be aString
or aFuture<String>
, but not anything else. In this case, that's not super useful beyond just stating a more precise type for readers of the code. It does give you a little better error checking in code that uses the result of that.FutureOr<T>
becomes really important in generic methods likeFuture.then()
. In those cases, having the type system understand this magical union type helps type inference figure out the type argument ofthen()
based on the closure you pass it.Previously, strong mode had hard-coded rules for handling
Future.then()
specifically.FutureOr<T>
exposes that functionality so third-party APIs can take advantage of it too.
Tool changes
-
Dart2Js
- Remove support for (long-time deprecated) mixin typedefs.
-
Pub
-
Avoid using a barback asset server for executables unless they actually use transformers. This makes precompilation substantially faster, produces better error messages when precompilation fails, and allows globally-activated executables to consistently use the
Isolate.resolvePackageUri()
API. -
On Linux systems, always ignore packages' original file owners and permissions when extracting those packages. This was already the default under most circumstances.
-
Properly close the standard input stream of child processes started using
pub run
. -
Handle parse errors from the package cache more gracefully. A package whose pubspec can't be parsed will now be ignored by
pub get --offline
and deleted bypub cache repair
. -
Make
pub run
run executables in spawned isolates. This lets them handle signals and use standard IO reliably. -
Fix source-maps produced by dart2js when running in
pub serve
: URL references to assets from packages match the location wherepub serve
serves them (packages/package_name/
instead of../packages/package_name/
).
-
Infrastructure changes
- The SDK now uses GN rather than gyp to generate its build files, which will
now be exclusively ninja flavored. Documentation can be found on our
wiki. Also see the
help message of
tools/gn.py
. This change is in response to the deprecation of gyp. Build file generation with gyp will continue to be available in this release by setting the environment variableDART_USE_GYP
before runninggclient sync
orgclient runhooks
, but this will be removed in a future release.
1.21.1 - 2017-01-13
Patch release, resolves one issue:
- Dart VM: Snapshots of generic functions fail. Issue 28072
1.21.0 - 2016-12-07
Language
-
Support generic method syntax. Type arguments are not available at runtime. For details, check the informal specification.
-
Support access to initializing formals, e.g., the use of
x
to initializey
inclass C { var x, y; C(this.x): y = x; }
. Please check the informal specification for details. -
Don't warn about switch case fallthrough if the case ends in a
rethrow
statement. (SDK issue 27650) -
Also don't warn if the entire switch case is wrapped in braces - as long as the block ends with a
break
,continue
,rethrow
,return
orthrow
. -
Allow
=
as well as:
as separator for named parameter default values.enableFlags({bool hidden: false}) { … }
can now be replaced by
enableFlags({bool hidden = false}) { … }
(SDK issue 27559)
Core library changes
-
dart:core
:Set.difference
now takes aSet<Object>
as argument. (SDK issue 27573) -
dart:developer
- Added
Service
class.- Allows inspecting and controlling the VM service protocol HTTP server.
- Provides an API to access the ID of an
Isolate
.
- Added
Tool changes
-
Dart Dev Compiler
- Support calls to
loadLibrary()
on deferred libraries. Deferred libraries are still loaded eagerly. (SDK issue 27343)
- Support calls to
1.20.1 - 2016-10-13
Patch release, resolves one issue:
- Dartium: Fixes a bug that caused crashes. No issue filed.
Strong Mode
-
It is no longer a warning when casting from dynamic to a composite type (SDK issue 27766).
main() { dynamic obj = <int>[1, 2, 3]; // This is now allowed without a warning. List<int> list = obj; }
1.20.0 - 2016-10-11
Dart VM
-
We have improved the way that the VM locates the native code library for a native extension (e.g.
dart-ext:
import). We have updated this article on native extensions to reflect the VM's improved behavior. -
Linux builds of the VM will now use the
tcmalloc
library for memory allocation. This has the advantages of better debugging and profiling support and faster small allocations, with the cost of slightly larger initial memory footprint, and slightly slower large allocations. -
We have improved the way the VM searches for trusted root certificates for secure socket connections on Linux. First, the VM will look for trusted root certificates in standard locations on the file system (
/etc/pki/tls/certs/ca-bundle.crt
followed by/etc/ssl/certs
), and only if these do not exist will it fall back on the builtin trusted root certificates. This behavior can be overridden on Linux with the new flags--root-certs-file
and--root-certs-cache
. The former is the path to a file containing the trusted root certificates, and the latter is the path to a directory containing root certificate files hashed usingc_rehash
. -
The VM now throws a catchable
Error
when method compilation fails. This allows easier debugging of syntax errors, especially when testing. (SDK issue 23684)
Core library changes
dart:core
: Remove deprecatedResource
class. Use the class inpackage:resource
instead.dart:async
Future.wait
now catches synchronous errors and returns them in the returned Future. (SDK issue 27249)- More aggressively returns a
Future
onStream.cancel
operations. Discourages to returnnull
fromcancel
. (SDK issue 26777) - Fixes a few bugs where the cancel future wasn't passed through transformations.
dart:io
- Added
WebSocket.addUtf8Text
to allow sending a pre-encoded text message without a round-trip UTF-8 conversion. (SDK issue 27129)
- Added
Strong Mode
-
Breaking change - it is an error if a generic type parameter cannot be inferred (SDK issue 26992).
class Cup<T> { Cup(T t); } main() { // Error because: // - if we choose Cup<num> it is not assignable to `cOfInt`, // - if we choose Cup<int> then `n` is not assignable to int. num n; C<int> cOfInt = new C(n); }
-
New feature - use
@checked
to override a method and tighten a parameter type (SDK issue 25578).import 'package:meta/meta.dart' show checked; class View { addChild(View v) {} } class MyView extends View { // this override is legal, it will check at runtime if we actually // got a MyView. addChild(@checked MyView v) {} } main() { dynamic mv = new MyView(); mv.addChild(new View()); // runtime error }
-
New feature - use
@virtual
to allow field overrides in strong mode (SDK issue 27384).import 'package:meta/meta.dart' show virtual; class Base { @virtual int x; } class Derived extends Base { int x; // Expose the hidden storage slot: int get superX => super.x; set superX(int v) { super.x = v; } }
-
Breaking change - infer list and map literals from the context type as well as their values, consistent with generic methods and instance creation (SDK issue 27151).
import 'dart:async'; main() async { var b = new Future<B>.value(new B()); var c = new Future<C>.value(new C()); var/*infer List<Future<A>>*/ list = [b, c]; var/*infer List<A>*/ result = await Future.wait(list); } class A {} class B extends A {} class C extends A {}
Tool changes
-
dartfmt
- upgraded to v0.2.10- Don't crash on annotations before parameters with trailing commas.
- Always split enum declarations if they end in a trailing comma.
- Add
--set-exit-if-changed
to set the exit code on a change.
-
Pub
- Pub no longer generates a
packages/
directory by default. Instead, it generates a.packages
file, called a package spec. To generate apackages/
directory in addition to the package spec, use the--packages-dir
flag withpub get
,pub upgrade
, andpub downgrade
. See the Good-bye symlinks article for details.
- Pub no longer generates a
1.19.1 - 2016-09-08
Patch release, resolves one issue:
- Dartdoc: Fixes a bug that prevented generation of docs. (Dartdoc issue 1233)
1.19.0 - 2016-08-26
Language changes
- The language now allows a trailing comma after the last argument of a call and the last parameter of a function declaration. This can make long argument or parameter lists easier to maintain, as commas can be left as-is when reordering lines. For details, see SDK issue 26644.
Tool Changes
-
dartfmt
- upgraded to v0.2.9+1- Support trailing commas in argument and parameter lists.
- Gracefully handle read-only files.
- About a dozen other bug fixes.
-
Pub
-
Added a
--no-packages-dir
flag topub get
,pub upgrade
, andpub downgrade
. When this flag is passed, pub will not generate apackages/
directory, and will remove that directory and any symlinks to it if they exist. Note that this replaces the unsupported--no-package-symlinks
flag. -
Added the ability for packages to declare a constraint on the Flutter SDK:
environment: flutter: ^0.1.2 sdk: >=1.19.0 <2.0.0
A Flutter constraint will only be satisfiable when pub is running in the context of the
flutter
executable, and when the Flutter SDK version matches the constraint. -
Added
sdk
as a new package source that fetches packages from a hard-coded SDK. Currently only theflutter
SDK is supported:dependencies: flutter_driver: sdk: flutter version: ^0.0.1
A Flutter
sdk
dependency will only be satisfiable when pub is running in the context of theflutter
executable, and when the Flutter SDK contains a package with the given name whose version matches the constraint. -
tar
files on Linux are now created with0
as the user and group IDs. This fixes a crash when publishing packages while using Active Directory. -
Fixed a bug where packages from a hosted HTTP URL were considered the same as packages from an otherwise-identical HTTPS URL.
-
Fixed timer formatting for timers that lasted longer than a minute.
-
Eliminate some false negatives when determining whether global executables are on the user's executable path.
-
-
dart2js
dart2dart
(akadart2js --output-type=dart
) has been removed (this was deprecated in Dart 1.11).
Dart VM
- The dependency on BoringSSL has been rolled forward. Going forward, builds of the Dart VM including secure sockets will require a compiler with C++11 support. For details, see the Building wiki page.
Strong Mode
-
New feature - an option to disable implicit casts (SDK issue 26583), see the documentation for usage instructions and examples.
-
New feature - an option to disable implicit dynamic (SDK issue 25573), see the documentation for usage instructions and examples.
-
Breaking change - infer generic type arguments from the constructor invocation arguments (SDK issue 25220).
var map = new Map<String, String>(); // infer: Map<String, String> var otherMap = new Map.from(map);
-
Breaking change - infer local function return type (SDK issue 26414).
void main() { // infer: return type is int f() { return 40; } int y = f() + 2; // type checks print(y); }
-
Breaking change - allow type promotion from a generic type parameter (SDK issue 26414).
void fn/*<T>*/(/*=T*/ object) { if (object is String) { // Treat `object` as `String` inside this block. // But it will require a cast to pass it to something that expects `T`. print(object.substring(1)); } }
-
Breaking change - smarter inference for Future.then (SDK issue 25944). Previous workarounds that use async/await or
.then/*<Future<SomeType>>*/
should no longer be necessary.// This will now infer correctly. Future<List<int>> t2 = f.then((_) => [3]); // This infers too. Future<int> t2 = f.then((_) => new Future.value(42));
-
Breaking change - smarter inference for async functions (SDK issue 25322).
void test() async { List<int> x = await [4]; // was previously inferred List<int> y = await new Future.value([4]); // now inferred too }
-
Breaking change - sideways casts are no longer allowed (SDK issue 26120).
1.18.1 - 2016-08-02
Patch release, resolves two issues and improves performance:
-
Debugger: Fixes a bug that crashes the VM (SDK issue 26941)
-
VM: Fixes an optimizer bug involving closures, try, and await (SDK issue 26948)
-
Dart2js: Speeds up generated code on Firefox (https://codereview.chromium.org/2180533002)
1.18.0 - 2016-07-27
Core library changes
dart:core
- Improved performance when parsing some common URIs.
- Fixed bug in
Uri.resolve
(SDK issue 26804).
dart:io
- Adds file locking modes
FileLock.BLOCKING_SHARED
andFileLock.BLOCKING_EXCLUSIVE
.
- Adds file locking modes
1.17.1 - 2016-06-10
Patch release, resolves two issues:
-
VM: Fixes a bug that caused crashes in async functions. (SDK issue 26668)
-
VM: Fixes a bug that caused garbage collection of reachable weak properties. (https://codereview.chromium.org/2041413005)
1.17.0 - 2016-06-08
Core library changes
-
dart:convert
- Deprecate
ChunkedConverter
which was erroneously added in 1.16.
- Deprecate
-
dart:core
Uri.replace
supports iterables as values for the query parameters.Uri.parseIPv6Address
returns aUint8List
.
-
dart:io
- Added
NetworkInterface.listSupported
, which istrue
whenNetworkInterface.list
is supported, andfalse
otherwise. Currently,NetworkInterface.list
is not supported on Android.
- Added
Tool Changes
-
Pub
-
TAR files created while publishing a package on Mac OS and Linux now use a more portable format.
-
Errors caused by invalid arguments now print the full usage information for the command.
-
SDK constraints for dependency overrides are no longer considered when determining the total SDK constraint for a lockfile.
-
A bug has been fixed in which a lockfile was considered up-to-date when it actually wasn't.
-
A bug has been fixed in which
pub get --offline
would crash when a prerelease version was selected.
-
-
Dartium and content shell
- Debugging Dart code inside iframes improved, was broken.
1.16.1 - 2016-05-24
Patch release, resolves one issue:
- VM: Fixes a bug that caused intermittent hangs on Windows. (SDK issue 26400)
1.16.0 - 2016-04-26
Core library changes
-
dart:convert
-
Added
BASE64URL
codec and correspondingBase64Codec.urlSafe
constructor. -
Introduce
ChunkedConverter
and deprecate chunked methods onConverter
.
-
-
dart:html
There have been a number of BREAKING changes to align APIs with recent changes in Chrome. These include:
-
Chrome's
ShadowRoot
interface no longer has the methodsgetElementById
,getElementsByClassName
, andgetElementsByTagName
, e.g.,elem.shadowRoot.getElementsByClassName('clazz')
should become:
elem.shadowRoot.querySelectorAll('.clazz')
-
The
clipboardData
property has been removed fromKeyEvent
andEvent
. It has been moved to the newClipboardEvent
class, which is now used bycopy
,cut
, andpaste
events. -
The
layer
property has been removed fromKeyEvent
andUIEvent
. It has been moved toMouseEvent
. -
The
Point get page
property has been removed fromUIEvent
. It still exists onMouseEvent
andTouch
.
There have also been a number of other additions and removals to
dart:html
,dart:indexed_db
,dart:svg
,dart:web_audio
, anddart:web_gl
that correspond to changes to Chrome APIs between v39 and v45. Many of the breaking changes represent APIs that would have caused runtime exceptions when compiled to Javascript and run on recent Chrome releases. -
-
dart:io
- Added
SecurityContext.alpnSupported
, which is true if a platform supports ALPN, and false otherwise.
- Added
JavaScript interop
For performance reasons, a potentially BREAKING change was added for
libraries that use JS interop.
Any Dart file that uses @JS
annotations on declarations (top-level functions,
classes or class members) to interop with JavaScript code will require that the
file have the annotation @JS()
on a library directive.
@JS()
library my_library;
The analyzer will enforce this by generating the error:
The @JS()
annotation can only be used if it is also declared on the library
directive.
If part file uses the @JS()
annotation, the library that uses the part should
have the @JS()
annotation e.g.,
// library_1.dart
@JS()
library library_1;
import 'package:js/js.dart';
part 'part_1.dart';
// part_1.dart
part of library_1;
@JS("frameworkStabilizers")
external List<FrameworkStabilizer> get frameworkStabilizers;
If your library already has a JS module e.g.,
@JS('array.utils')
library my_library;
Then your library will work without any additional changes.
Analyzer
-
Static checking of
for in
statements. These will now produce static warnings:// Not Iterable. for (var i in 1234) { ... } // String cannot be assigned to int. for (int n in <String>["a", "b"]) { ... }
Tool Changes
-
Pub
-
pub serve
now provides caching headers that should improve the performance of requesting large files multiple times. -
Both
pub get
andpub upgrade
now have a--no-precompile
flag that disables precompilation of executables and transformed dependencies. -
pub publish
now resolves symlinks when publishing from a Git repository. This matches the behavior it always had when publishing a package that wasn't in a Git repository.
-
-
Dart Dev Compiler
-
The experimental
dartdevc
executable has been added to the SDK. -
It will help early adopters validate the implementation and provide feedback.
dartdevc
is not yet ready for production usage. -
Read more about the Dart Dev Compiler here.
-
1.15.0 - 2016-03-09
Core library changes
-
dart:async
- Made
StreamView
class aconst
class.
- Made
-
dart:core
- Added
Uri.queryParametersAll
to handle multiple query parameters with the same name.
- Added
-
dart:io
- Added
SecurityContext.usePrivateKeyBytes
,SecurityContext.useCertificateChainBytes
,SecurityContext.setTrustedCertificatesBytes
, andSecurityContext.setClientAuthoritiesBytes
. - Breaking The named
directory
argument ofSecurityContext.setTrustedCertificates
has been removed. - Added support to
SecurityContext
for PKCS12 certificate and key containers. - All calls in
SecurityContext
that accept certificate data now accept an optional named parameterpassword
, similar toSecurityContext.usePrivateKeyBytes
, for use as the password for PKCS12 data.
- Added
Tool changes
-
Dartium and content shell
- The Chrome-based tools that ship as part of the Dart SDK – Dartium and content shell – are now based on Chrome version 45 (instead of Chrome 39).
- Dart browser libraries (
dart:html
,dart:svg
, etc) have not been updated.- These are still based on Chrome 39.
- These APIs will be updated in a future release.
- Note that there are experimental APIs which have changed in the underlying
browser, and will not work with the older libraries.
For example,
Element.animate
.
-
dartfmt
- upgraded to v0.2.4- Better handling for long collections with comments.
- Always put member metadata annotations on their own line.
- Indent functions in named argument lists with non-functions.
- Force the parameter list to split if a split occurs inside a function-typed parameter.
- Don't force a split for before a single named argument if the argument itself splits.
Service protocol changes
- Fixed a documentation bug where the field
extensionRPCs
inIsolate
was not marked optional.
Experimental language features
-
Added support for configuration-specific imports. On the VM and
dart2js
, they can be enabled with--conditional-directives
.The analyzer requires additional configuration:
analyzer: language: enableConditionalDirectives: true
Read about configuring the analyzer for more details.
1.14.2 - 2016-02-10
Patch release, resolves three issues:
-
VM: Fixed a code generation bug on x64. (SDK commit 834b3f02)
-
dart:io
: Fixed EOF detection when reading some special device files. (SDK issue 25596) -
Pub: Fixed an error using hosted dependencies in SDK version 1.14. (Pub issue 1386)
1.14.1 - 2016-02-04
Patch release, resolves one issue:
- Debugger: Fixes a VM crash when a debugger attempts to set a break point during isolate initialization. (SDK issue 25618)
1.14.0 - 2016-01-28
Core library changes
-
dart:async
- Added
Future.any
static method. - Added
Stream.fromFutures
constructor.
- Added
-
dart:convert
Base64Decoder.convert
now takes optionalstart
andend
parameters.
-
dart:core
- Added
current
getter toStackTrace
class. Uri
class added support for data URIs- Added two new constructors:
dataFromBytes
anddataFromString
. - Added a
data
getter fordata:
URIs with a newUriData
class for the return type.
- Added two new constructors:
- Added
growable
parameter toList.filled
constructor. - Added microsecond support to
DateTime
:DateTime.microsecond
,DateTime.microsecondsSinceEpoch
, andnew DateTime.fromMicrosecondsSinceEpoch
.
- Added
-
dart:math
Random
added asecure
constructor returning a cryptographically secure random generator which reads from the entropy source provided by the embedder for every generated random value.
-
dart:io
Platform
added a staticisIOS
getter andPlatform.operatingSystem
may now returnios
.Platform
added a staticpackageConfig
getter.- Added support for WebSocket compression as standardized in RFC 7692.
- Compression is enabled by default for all WebSocket connections.
- The optionally named parameter
compression
on the methodsWebSocket.connect
,WebSocket.fromUpgradedSocket
, andWebSocketTransformer.upgrade
and theWebSocketTransformer
constructor can be used to modify or disable compression using the newCompressionOptions
class.
- The optionally named parameter
-
dart:isolate
- Added experimental support for Package Resolution Configuration.
- Added
packageConfig
andpackageRoot
instance getters toIsolate
. - Added a
resolvePackageUri
method toIsolate
. - Added named arguments
packageConfig
andautomaticPackageResolution
to theIsolate.spawnUri
constructor.
- Added
- Added experimental support for Package Resolution Configuration.
Tool changes
-
dartfmt
-
Better line splitting in a variety of cases.
-
Other optimizations and bug fixes.
-
-
Pub
-
Breaking: Pub now eagerly emits an error when a pubspec's "name" field is not a valid Dart identifier. Since packages with non-identifier names were never allowed to be published, and some of them already caused crashes when being written to a
.packages
file, this is unlikely to break many people in practice. -
Breaking: Support for
barback
versions prior to 0.15.0 (released July- has been dropped. Pub will no longer install these older barback versions.
-
pub serve
now GZIPs the assets it serves to make load times more similar to real-world use-cases. -
pub deps
now supports a--no-dev
flag, which causes it to emit the dependency tree as it would be if nodev_dependencies
were in use. This makes it easier to see your package's dependency footprint as your users will experience it. -
pub global run
now detects when a global executable's SDK constraint is no longer met and errors out, rather than trying to run the executable anyway. -
Pub commands that check whether the lockfile is up-to-date (
pub run
,pub deps
,pub serve
, andpub build
) now do additional verification. They ensure that any path dependencies' pubspecs haven't been changed, and they ensure that the current SDK version is compatible with all dependencies. -
Fixed a crashing bug when using
pub global run
on a global script that didn't exist. -
Fixed a crashing bug when a pubspec contains a dependency without a source declared.
-
1.13.2 - 2016-01-06
Patch release, resolves one issue:
- dart2js: Stack traces are not captured correctly (SDK issue [25235] (https://github.com/dart-lang/sdk/issues/25235))
1.13.1 - 2015-12-17
Patch release, resolves three issues:
-
VM type propagation fix: Resolves a potential crash in the Dart VM (SDK commit [
dff13be
] (dff13bef8d
)) -
dart2js crash fix: Resolves a crash in pkg/js and dart2js (SDK issue [24974] (https://github.com/dart-lang/sdk/issues/24974))
-
Pub get crash on ARM: Fixes a crash triggered when running 'pub get' on ARM processors such as those on a Raspberry Pi (SDK issue [24855] (https://github.com/dart-lang/sdk/issues/24855))
1.13.0 - 2015-11-18
Core library changes
-
dart:async
StreamController
added getters foronListen
,onPause
, andonResume
with the corresponding newtypedef void ControllerCallback()
.StreamController
added a getter foronCancel
with the corresponding newtypedef ControllerCancelCallback()
;StreamTransformer
instances created withfromHandlers
with nohandleError
callback now forward stack traces along with errors to the resulting streams.
-
dart:convert
- Added support for Base-64 encoding and decoding.
- Added new classes
Base64Codec
,Base64Encoder
, andBase64Decoder
. - Added new top-level
const Base64Codec BASE64
.
- Added new classes
- Added support for Base-64 encoding and decoding.
-
dart:core
Uri
addedremoveFragment
method.String.allMatches
(implementingPattern.allMatches
) is now lazy, as allallMatches
implementations are intended to be.Resource
is deprecated, and will be removed in a future release.
-
dart:developer
- Added
Timeline
class for interacting with Observatory's timeline feature. - Added
ServiceExtensionHandler
,ServiceExtensionResponse
, andregisterExtension
which enable developers to provide their own VM service protocol extensions.
- Added
-
dart:html
,dart:indexed_db
,dart:svg
,dart:web_audio
,dart:web_gl
,dart:web_sql
- The return type of some APIs changed from
double
tonum
. Dartium is now using JS interop for most operations. JS does not distinguish between numeric types, and will return a number as an int if it fits in an int. This will mostly cause an error if you assign to something typeddouble
in checked mode. You may need to insert atoDouble()
call or acceptnum
. Examples of APIs that are affected includeElement.getBoundingClientRect
andTextMetrics.width
.
- The return type of some APIs changed from
-
dart:io
-
Breaking: Secure networking has changed, replacing the NSS library with the BoringSSL library.
SecureSocket
,SecureServerSocket
,RawSecureSocket
,RawSecureServerSocket
,HttpClient
, andHttpServer
now all use aSecurityContext
object which contains the certificates and keys used for secure TLS (SSL) networking.This is a breaking change for server applications and for some client applications. Certificates and keys are loaded into the
SecurityContext
from PEM files, instead of from an NSS certificate database. Information about how to change applications that use secure networking is at https://www.dartlang.org/server/tls-ssl.html -
HttpClient
no longer sends URI fragments in the request. This is not allowed by the HTTP protocol. TheHttpServer
still gracefully receives fragments, but discards them before delivering the request. -
To allow connections to be accepted on the same port across different isolates, set the
shared
argument totrue
when creating server socket andHttpServer
instances.- The deprecated
ServerSocketReference
andRawServerSocketReference
classes have been removed. - The corresponding
reference
properties onServerSocket
andRawServerSocket
have been removed.
- The deprecated
-
-
dart:isolate
spawnUri
added anenvironment
named argument.
Tool changes
-
dart2js
and Dartium now support improved Javascript Interoperability via the js package. -
docgen
anddartdocgen
no longer ship in the SDK. Thedocgen
sources have been removed from the repository. -
This is the last release to ship the VM's "legacy debug protocol". We intend to remove the legacy debug protocol in Dart VM 1.14.
-
The VM's Service Protocol has been updated to version 3.0 to take care of a number of issues uncovered by the first few non-observatory clients. This is a potentially breaking change for clients.
-
Dartium has been substantially changed. Rather than using C++ calls into Chromium internals for DOM operations it now uses JS interop. The DOM objects in
dart:html
and related libraries now wrap a JavaScript object and delegate operations to it. This should be mostly transparent to users. However, performance and memory characteristics may be different from previous versions. There may be some changes in which DOM objects are wrapped as Dart objects. For example, if you get a reference to a Window object, even through JS interop, you will always see it as a Dart Window, even when used cross-frame. We expect the change to using JS interop will make it much simpler to update to new Chrome versions.
1.12.2 - 2015-10-21
Core library changes
-
dart:io
- A memory leak in creation of Process objects is fixed.
1.12.1 - 2015-09-08
Tool changes
-
Pub
-
Pub will now respect
.gitignore
when validating a package before it's published. For example, if aLICENSE
file exists but is ignored, that is now an error. -
If the package is in a subdirectory of a Git repository and the entire subdirectory is ignored with
.gitignore
, pub will act as though nothing was ignored instead of uploading an empty package. -
The heuristics for determining when
pub get
needs to be run before various commands have been improved. There should no longer be false positives when non-dependency sections of the pubspec have been modified.
-
1.12.0 - 2015-08-31
Language changes
- Null-aware operators
??
: if null operator.expr1 ?? expr2
evaluates toexpr1
if notnull
, otherwiseexpr2
.??=
: null-aware assignment.v ??= expr
causesv
to be assignedexpr
only ifv
isnull
.x?.p
: null-aware access.x?.p
evaluates tox.p
ifx
is notnull
, otherwise evaluates tonull
.x?.m()
: null-aware method invocation.x?.m()
invokesm
only ifx
is notnull
.
Core library changes
-
dart:async
StreamController
added setters for theonListen
,onPause
,onResume
andonCancel
callbacks.
-
dart:convert
LineSplitter
added asplit
static method returning anIterable
.
-
dart:core
Uri
class now perform path normalization when a URI is created. This removes most..
and.
sequences from the URI path. Purely relative paths (no scheme or authority) are allowed to retain some leading "dot" segments. Also addedhasAbsolutePath
,hasEmptyPath
, andhasScheme
properties.
-
dart:developer
- New
log
function to transmit logging events to Observatory.
- New
-
dart:html
NodeTreeSanitizer
added theconst trusted
field. It can be used instead of defining aNullTreeSanitizer
class when callingsetInnerHtml
or other methods that create DOM from text. It is also more efficient, skipping the creation of aDocumentFragment
.
-
dart:io
-
dart:isolate
- Added
onError
,onExit
anderrorsAreFatal
parameters toIsolate.spawnUri
.
- Added
-
dart:mirrors
InstanceMirror.delegate
moved up toObjectMirror
.- Fix InstanceMirror.getField optimization when the selector is an operator.
- Fix reflective NoSuchMethodErrors to match their non-reflective counterparts when due to argument mismatches. (VM only)
Tool changes
-
Documentation tools
-
dartdoc
is now the default tool to generate static HTML for API docs. Learn more. -
docgen
anddartdocgen
have been deprecated. Currently plan is to remove them in 1.13.
-
-
Formatter (
dartfmt
)-
Over 50 bugs fixed.
-
Optimized line splitter is much faster and produces better output on complex code.
-
-
Observatory
-
Allocation profiling.
-
New feature to display output from logging.
-
Heap snapshot analysis works for 64-bit VMs.
-
Improved ability to inspect typed data, regex and compiled code.
-
Ability to break on all or uncaught exceptions from Observatory's debugger.
-
Ability to set closure-specific breakpoints.
-
'anext' - step past await/yield.
-
Preserve when a variable has been expanded/unexpanded in the debugger.
-
Keep focus on debugger input box whenever possible.
-
Echo stdout/stderr in the Observatory debugger. Standalone-only so far.
-
Minor fixes to service protocol documentation.
-
-
Pub
-
Breaking: various commands that previously ran
pub get
implicitly no longer do so. Instead, they merely check to make sure the ".packages" file is newer than the pubspec and the lock file, and fail if it's not. -
Added support for
--verbosity=error
and--verbosity=warning
. -
pub serve
now collapses multiple GET requests into a single line of output. For full output, use--verbose
. -
pub deps
has improved formatting for circular dependencies on the entrypoint package. -
pub run
andpub global run
-
Breaking: to match the behavior of the Dart VM, executables no longer run in checked mode by default. A
--checked
flag has been added to run them in checked mode manually. -
Faster start time for executables that don't import transformed code.
-
Binstubs for globally-activated executables are now written in the system encoding, rather than always in
UTF-8
. To update existing executables, runpub cache repair
.
-
-
pub get
andpub upgrade
-
Pub will now generate a ".packages" file in addition to the "packages" directory when running
pub get
or similar operations, per the package spec proposal. Pub now has a--no-package-symlinks
flag that will stop "packages" directories from being generated at all. -
An issue where HTTP requests were sometimes made even though
--offline
was passed has been fixed. -
A bug with
--offline
that caused an unhelpful error message has been fixed. -
Pub will no longer time out when a package takes a long time to download.
-
-
pub publish
-
Pub will emit a non-zero exit code when it finds a violation while publishing.
-
.gitignore
files will be respected even if the package isn't at the top level of the Git repository.
-
-
Barback integration
-
A crashing bug involving transformers that only apply to non-public code has been fixed.
-
A deadlock caused by declaring transformer followed by a lazy transformer (such as the built-in
$dart2js
transformer) has been fixed. -
A stack overflow caused by a transformer being run multiple times on the package that defines it has been fixed.
-
A transformer that tries to read a non-existent asset in another package will now be re-run if that asset is later created.
-
-
VM Service Protocol Changes
-
BREAKING The service protocol now sends JSON-RPC 2.0-compatible server-to-client events. To reflect this, the service protocol version is now 2.0.
-
The service protocol now includes a
"jsonrpc"
property in its responses, as opposed to"json-rpc"
. -
The service protocol now properly handles requests with non-string ids. Numeric ids are no longer converted to strings, and null ids now don't produce a response.
-
Some RPCs that didn't include a
"jsonrpc"
property in their responses now include one.
1.11.2 - 2015-08-03
Core library changes
- Fix a bug where
WebSocket.close()
would crash if called afterWebSocket.cancel()
.
1.11.1 - 2015-07-02
Tool changes
- Pub will always load Dart SDK assets from the SDK whose
pub
executable was run, even if aDART_SDK
environment variable is set.
1.11.0 - 2015-06-25
Core library changes
-
dart:core
Iterable
added anempty
constructor. dcf0286Iterable
can now be extended directly. An alternative to extendingIterableBase
fromdart:collection
.List
added anunmodifiable
constructor. r45334Map
added anunmodifiable
constructor. r45733int
added agcd
method. a192ef4int
added amodInverse
method. f6f338cStackTrace
added afromString
constructor. 68dd6f6Uri
added adirectory
constructor. d8dbb4a- List iterators may not throw
ConcurrentModificationError
as eagerly in release mode. In checked mode, the modification check is still as eager as possible. r45198
-
dart:developer
- NEW- Replaces the deprecated
dart:profiler
library. - Adds new functions
debugger
andinspect
. 6e42aec
- Replaces the deprecated
-
dart:io
-
dart:html
Element
methods,appendHtml
andinsertAdjacentHtml
now takenodeValidator
andtreeSanitizer
parameters, and the inputs are consistently sanitized. r45818 announcement
-
dart:isolate
- BREAKING The positional
priority
parameter ofIsolate.ping
andIsolate.kill
is now a named parameter namedpriority
. - BREAKING Removed the
Isolate.AS_EVENT
priority. Isolate
methodsping
andaddOnExitListener
now have a named parameterresponse
. r45092Isolate.spawnUri
added a named argumentchecked
.- Remove the experimental state of the API.
- BREAKING The positional
-
dart:profiler
- DEPRECATED- This library will be removed in 1.12. Use
dart:developer
instead.
- This library will be removed in 1.12. Use
Tool changes
- This is the first release that does not include the Eclipse-based Dart Editor. See dartlang.org/tools for alternatives.
- This is the last release that ships the (unsupported)
dart2dart (aka
dart2js --output-type=dart
) utility as part of dart2js
1.10.0 – 2015-04-29
Core library changes
-
dart:convert
-
dart:core
Uri.parse
addedstart
andend
positional arguments.
-
dart:html
- POTENTIALLY BREAKING
CssClassSet
method arguments must now be 'tokens', i.e. non-empty strings with no white-space characters. The implementation was incorrect for class names containing spaces. The fix is to forbid spaces and provide a faster implementation. Announcement
- POTENTIALLY BREAKING
-
dart:io
ProcessResult
now exposes a constructor.import
andIsolate.spawnUri
now supports the Data URI scheme on the VM.
Tool Changes
pub
-
Running
pub run foo
within a package now runs thefoo
executable defined by thefoo
package. The previous behavior ranbin/foo
. This makes it easy to run binaries in dependencies, for instancepub run test
. -
On Mac and Linux, signals sent to
pub run
and forwarded to the child command.
1.9.3 – 2015-04-14
This is a bug fix release which merges a number of commits from bleeding_edge
.
-
dart2js: Addresses as issue with minified Javascript output with CSP enabled - r44453
-
Editor: Fixes accidental updating of files in the pub cache during rename refactoring - r44677
-
Editor: Fix for issue 23032 regarding skipped breakpoints on Windows - r44824
-
dart:mirrors: Fix
MethodMirror.source
when the method is on the first line in a script - r44957, r44976 -
pub: Fix for issue 23084: Pub can fail to load transformers necessary for local development - r44876
1.9.1 – 2015-03-25
Language changes
-
Support for
async
,await
,sync*
,async*
,yield
,yield*
, andawait for
. See the the language tour for more details. -
Enum support is fully enabled. See the language tour for more details.
Tool changes
-
The formatter is much more comprehensive and generates much more readable code. See its tool page for more details.
-
The analysis server is integrated into the IntelliJ plugin and the Dart editor. This allows analysis to run out-of-process, so that interaction remains smooth even for large projects.
-
Analysis supports more and better hints, including unused variables and unused private members.
Core library changes
Highlights
-
There's a new model for shared server sockets with no need for a
Socket
reference. -
A new, much faster regular expression engine.
-
The Isolate API now works across the VM and
dart2js
.
Details
For more information on any of these changes, see the corresponding documentation on the Dart API site.
-
dart:async
:-
Future.wait
added a new named argument,cleanUp
, which is a callback that releases resources allocated by a successfulFuture
. -
The
SynchronousStreamController
class was added as an explicit name for the type returned when thesync
argument is passed tonew StreamController
.
-
-
dart:collection
: Thenew SplayTreeSet.from(Iterable)
constructor was added. -
dart:convert
:Utf8Encoder.convert
andUtf8Decoder.convert
added optionalstart
andend
arguments. -
dart:core
:-
RangeError
added new static helper functions:checkNotNegative
,checkValidIndex
,checkValidRange
, andcheckValueInInterval
. -
int
added themodPow
function. -
String
added thereplaceFirstMapped
andreplaceRange
functions.
-
-
dart:io
:-
Support for locking files to prevent concurrent modification was added. This includes the
File.lock
,File.lockSync
,File.unlock
, andFile.unlockSync
functions as well as theFileLock
class. -
Support for starting detached processes by passing the named
mode
argument (aProcessStartMode
) toProcess.start
. A process can be fully attached, fully detached, or detached except for its standard IO streams. -
HttpServer.bind
andHttpServer.bindSecure
added thev6Only
named argument. If this is true, only IPv6 connections will be accepted. -
HttpServer.bind
,HttpServer.bindSecure
,ServerSocket.bind
,RawServerSocket.bind
,SecureServerSocket.bind
andRawSecureServerSocket.bind
added theshared
named argument. If this is true, multiple servers or sockets in the same Dart process may bind to the same address, and incoming requests will automatically be distributed between them. -
Deprecation: the experimental
ServerSocketReference
andRawServerSocketReference
classes, as well as getters that returned them, are marked as deprecated. Theshared
named argument should be used instead. These will be removed in Dart 1.10. -
Socket.connect
andRawSocket.connect
added thesourceAddress
named argument, which specifies the local address to bind when making a connection. -
The static
Process.killPid
method was added to kill a process with a given PID. -
Stdout
added thenonBlocking
instance property, which returns a non-blockingIOSink
that writes to standard output.
-
-
dart:isolate
:-
The static getter
Isolate.current
was added. -
The
Isolate
methodsaddOnExitListener
,removeOnExitListener
,setErrorsFatal
,addOnErrorListener
, andremoveOnErrorListener
now work on the VM. -
Isolates spawned via
Isolate.spawn
now allow most objects, including top-level and static functions, to be sent between them.
-
1.8.5 – 2015-01-21
-
Code generation for SIMD on ARM and ARM64 is fixed.
-
A possible crash on MIPS with newer GCC toolchains has been prevented.
-
A segfault when using
rethrow
was fixed (issue 21795).
1.8.3 – 2014-12-10
-
Breakpoints can be set in the Editor using file suffixes (issue 21280).
-
IPv6 addresses are properly handled by
HttpClient
indart:io
, fixing a crash in pub (issue 21698). -
Issues with the experimental
async
/await
syntax have been fixed. -
Issues with a set of number operations in the VM have been fixed.
-
ListBase
indart:collection
always returns anIterable
with the correct type argument.
1.8.0 – 2014-11-28
-
dart:collection
:SplayTree
added thetoSet
function. -
dart:convert
: TheJsonUtf8Encoder
class was added. -
dart:core
:-
The
IndexError
class was added for errors caused by an index being outside its expected range. -
The
new RangeError.index
constructor was added. It forwards tonew IndexError
. -
RangeError
added three new properties.invalidProperty
is the value that caused the error, andstart
andend
are the minimum and maximum values that the value is allowed to assume. -
new RangeError.value
andnew RangeError.range
added an optionalmessage
argument. -
The
new String.fromCharCodes
constructor added optionalstart
andend
arguments.
-
-
dart:io
:-
Support was added for the Application-Layer Protocol Negotiation extension to the TLS protocol for both the client and server.
-
SecureSocket.connect
,SecureServerSocket.bind
,RawSecureSocket.connect
,RawSecureSocket.secure
,RawSecureSocket.secureServer
, andRawSecureServerSocket.bind
added asupportedProtocols
named argument for protocol negotiation. -
RawSecureServerSocket
added asupportedProtocols
field. -
RawSecureSocket
andSecureSocket
added aselectedProtocol
field which contains the protocol selected during protocol negotiation.
-
1.7.0 – 2014-10-15
Tool changes
-
pub
now generates binstubs for packages that are globally activated so that they can be put on the user'sPATH
and used as normal executables. See thepub global activate
documentation. -
When using
dart2js
, deferred loading now works with multiple Dart apps on the same page.
Core library changes
-
dart:async
:Zone
,ZoneDelegate
, andZoneSpecification
added theerrorCallback
function, which allows errors that have been programmatically added to aFuture
orStream
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 newautoCompress
property can be set totrue
to re-enable compression.
-
-
dart:isolate
:Isolate.spawnUri
added the optionalpackageRoot
argument, which controls how it resolvespackage:
URIs.