1.3-M2

Compiler

New Features

• KT-6592 Support local variable initialization in lambda arguments to some functions
• KT-19323 Allow generic type parameter to have mixed constraints for @InlineOnly functions
• KT-24857 Support compatibility wrappers for coroutines in compiler
• KT-25320 Support limited conversions for constants to simplify interop for Kotlin/Native
• KT-25372 Support JvmName on annotation property getters
• KT-25495 Release contract DSL as experimental
• KT-25557 Metadata that maps coroutine label to the file name and line number
• KT-25559 Metadata that maps coroutine spilled state to local variables
• KT-25655 Safe or non-null calls required on x following check(x != null)
• KT-25972 Support reading binary metadata of the next major release

Performance Improvements

• KT-24657 Compiler performance issues with big files
• KT-26243 Avoid redundant "specialized" method for suspend lambdas.

Fixes

• KT-19628 Unresolved reference not reported on data class constructor [@get](https://github.com/get) annotation
• KT-20830 Nulls can propagate through "enhanced nullability" types on module boundaries
• KT-21240 Remove suspendCoroutineOrReturn intrinsic from compiler
• KT-22379 Condition of while-loop with break can produce unsound smartcast
• KT-23438 Back-end (JVM) Internal error: Failed to generate function suspendCoroutineOrReturn
• KT-23819 Inline classes: mapping of fully generic classes
• KT-23857 Annotation with target TYPE is not applicable to TYPE_USE in Java sources
• KT-24717 Allow number literals to be used as unsigned ones with unsigned expected typed
• KT-24860 Forbid usage function expression as suspend function expression
• KT-24872 Do not generate user-defined methods inside box class of inline class
• KT-24873 Generate equals/hashCode/toString methods for inline classes same as for data classes
• KT-25246 Incorrect bytecode generated for secondary constructor in inline class + primitive array
• KT-25278 No smart cast for "returns() implies" contract when default argument is omitted
• KT-25287 Getter-targeted annotations on annotation constructor parameters are lost
• KT-25293 “Couldn't transform method node” error on compiling inline class with hashCode() method call when underlying value type is basic (number, char, boolean)
• KT-25299 NoSuchMethodError Foo$Erased.hashCode(Ljava/lang/Object;) for hashCode(), toString() and equals() methods in inline classes
• KT-25328 “Couldn't transform method node” error on compiling inline class which is wrapping Unit type
• KT-25330 CCE “[Ljava.lang.Integer; cannot be cast to Foo” for inline class which is wrapping Array
• KT-25521 Coroutines state machine in Kotlin 1.3 should not have getLabel/setLabel
• KT-25558 Stabilize field naming and mangling for suspending lambda classes
• KT-25580 No warning about experimental API when unsigned types are inferred
• KT-25599 “Exception during code generation” on compiling code with public constructor of unsigned numbers array
• KT-25614 Support secondary constructors for inline classes
• KT-25683 Compiler support for calling experimental suspend functions and function with experimental suspend function type as parameter
• KT-25688 Add $continuation to LVT
• KT-25750 CCE “Foo cannot be cast to java.lang.String” with inline class
• KT-25760 Inline data class throws java.lang.VerifyError when trying toString() it
• KT-25794 Incorrect code generated for accessing elements of Array where C is inline class
• KT-25824 Move SuspendFunctionN fictitious interfaces to kotlin.coroutines package
• KT-25825 Allow to distinguish instances of function types from instances of suspend function types via kotlin.coroutines.jvm.internal.SuspendFunction marker interface
• KT-25912 Calling groupingBy+reduce from suspend function causes IncompatibleClassChangeError
• KT-25914 '==' for inline class with custom 'equals' uses underlying primitive type comparison instead
• KT-25973 Report metadata version mismatch upon discovering a .kotlin_module file in the dependencies with an incompatible metadata version
• KT-25981 Incorrect code generated for unboxed to boxed inline class equality
• KT-25983 Inline class equality uses IEEE 754 instead of total order
• KT-26029 Prohibit delegated properties inside inline classes
• KT-26030 Prohibit implementation by delegation for inline classes
• KT-26052 Inline Classes: IllegalArgumentException when underlying type is non-null but declared type is nullable
• KT-26101 Prohibit inline classes with recursive underlying types
• KT-26103 Inline class with type parameters is inconsistently mapped to JVM type if underlying type is a primitive
• KT-26120 Inline Classes: Class inheritance is allowed but fails when referencing a superclass member

IDE

• KT-25316 PARTIAL resolve mode doesn't work when effects system is enabled
• KT-25611 With Language / API version = "Latest stable" installing 1.3-M1 plugin upgrades actual values to 1.3
• KT-25681 Remove "Coroutines (experimental)" settings from IDE and do not pass -Xcoroutines to JPS compiler (since 1.3)
• KT-25714 Kotlin plugin updater suggests plugins incompatible with current Studio build platform
• KT-26239 New MPP template: add kotlin-test libraries to the modules dependencies by default
• KT-26290 Gradle Import: When all modules have the same language/API version use it for project-level settings as well

IDE. Completion

• KT-25275 Code completion does not take into account smart casts gotten from "returns implies" contract

IDE. Inspections and Intentions

• KT-22330 "Add remaining branch" quickfix doesn't properly import enum class
• KT-22354 "Add remaining branches with import" quick fix causes KNPE at ImportAllMembersIntention$Companion.importReceiverMembers()
• KT-26158 KNPE in "Create local variable"

IDE. Multiplatform

• KT-26217 "org.jetbrains.kotlin.resolve.MultiTargetPlatform$Common cannot be cast to org.jetbrains.kotlin.resolve.MultiTargetPlatform$Specific" on splitted actuals

IDE. Script

• KT-25814 IDE scripting console -> kotlin (JSR-223) - compilation errors - unresolved IDEA classes
• KT-25822 jvmTarget from the script compiler options is ignored in the IDE

JavaScript

• KT-22053 JS: Secondary constructor of Throwable inheritor doesn't call to primary one
• KT-25014 Support 'when' with subject variable in JS back-end
• KT-26064 JS inliner calls wrong constructor in incremental build
• KT-26117 JS runtime error: ArrayList_init instead of ArrayList_init_0
• KT-26138 JS: prohibit external inline class
• KT-26171 Prohibit inline classes as parameter and return type of external declaration

Language design

• KT-7566 Annotate kotlin.test.Test.assertNotNull() so that safe dereference isn't required after it
• KT-14397 Make "smart cast" to non-null string working after isNullOrEmpty() check.
• KT-19532 Evaluation order for constructor call
• KT-22274 Restrict statement labels applicability

Libraries

New Features

• KT-13814 keys.associateWith { k -> v } function
• KT-15539 Random Convenience Method in Ranges (LongRange, IntRange, etc)
• KT-15695 String/Collection/Map/Array/Sequence.ifEmpty { null }
• KT-18986 Debug-friendly toString implementation for CoroutineImpl
• KT-25570 Random extensions to generate unsigned random numbers
• KT-25659 Consider adding SuccessOrFailure.getOrDefault function
• KT-25874 Support array copying between two existing arrays
• KT-25875 Need more access to raw underlying array in unsigned arrays
• KT-25962 Add contract for 'synchronized'
• KT-26339 Introduce CoroutineStackFrame interface for coroutine stack reconstruction in debugger

Fixes

• KT-16097 Index overflow when sequence has more than Int.MAX_VALUE elements
• KT-17176 Long/Int progressions with Long.MIN_VALUE and Int.MIN_VALUE step are weird
• KT-19305 IOStreams#readBytes is badly named
• KT-19489 Array.copyOfRange returns value violating declared type when bounds are out of range
• KT-21049 Different behavior in split by regex at JVM and JS
• KT-23799 Discontinue deprecated artifacts distribution: kotlin-runtime, kotlin-jslib, kotlin-stdlib-jre7/8
• KT-25274 contract() function has internal visibility
• KT-25303 checkNotNull(T?) has no contract in contrast to checkNotNull(T?, () -> Any)
• KT-25771 SuccessOrFailure.isFailure always returns false when boxed
• KT-25961 Provide a way to create default-initialized 'U*Array'
• KT-26161 String-to-number and number-to-string conversions for unsigned integers

Reflection

• KT-14657 Reflection: Provide ability to enumerate all cases of a sealed class
• KT-16795 KType does not implement KAnnotatedElement
• KT-21972 Reflection: Implement suspend functions KCallable.callSuspend, callSuspendBy, and isSuspend

Tools. CLI

• KT-25823 Report a warning or error if an old language version or API version is used

Tools. Gradle

• KT-26301 In new MPP, a project with no java or java-base plugin applied cannot depend on a published MPP lib or run tests

Tools. Scripts

• KT-26142 update maven-central remote repository url