Skip to content

Commit

Permalink
feat: Kotlin 2.1.20-RC2 release (#4732)
Browse files Browse the repository at this point in the history
  • Loading branch information
@danil-pavlov
danil-pavlov authored Mar 6, 2025
1 parent 96990c6 commit e5aa8ec
Show file tree
Hide file tree
Showing 4 changed files with 143 additions and 19 deletions.
2 changes: 1 addition & 1 deletion docs/kr.tree
View file
Original file line number Diff line number Diff line change
Expand Up @@ -24,7 +24,7 @@
</toc-element>
<toc-element toc-title="What's new in Kotlin">
<toc-element toc-title="Kotlin 2.1.0" accepts-web-file-names="whatsnew.html" topic="whatsnew21.md"/>
<toc-element toc-title="Kotlin 2.1.20-RC" topic="whatsnew-eap.md"/>
<toc-element toc-title="Kotlin 2.1.20-RC2" topic="whatsnew-eap.md"/>
<toc-element toc-title="Earlier versions">
<toc-element toc-title="Kotlin 2.0.20" topic="whatsnew2020.md"/>
<toc-element toc-title="Kotlin 2.0.0" topic="whatsnew20.md"/>
Expand Down
8 changes: 4 additions & 4 deletions docs/topics/eap.md
View file
Original file line number Diff line number Diff line change
Expand Up @@ -43,13 +43,13 @@ In this channel, you can also get notifications about new EAP builds.
<th>Build highlights</th>
</tr>
<tr>
<td><strong>2.1.20-RC</strong>
<p>Released: <strong>February 19, 2025</strong></p>
<p><a href="https://github.com/JetBrains/kotlin/releases/tag/v2.1.20-RC" target="_blank">Release on GitHub</a></p>
<td><strong>2.1.20-RC2</strong>
<p>Released: <strong>March 6, 2025</strong></p>
<p><a href="https://github.com/JetBrains/kotlin/releases/tag/v2.1.20-RC2" target="_blank">Release on GitHub</a></p>
</td>
<td>
<p>A tooling release with K2 kapt enabled by default.</p>
<p>For more details, please refer to the <a href="https://github.com/JetBrains/kotlin/releases/tag/v2.1.20-RC">changelog</a> or <a href="whatsnew-eap.md">What's new in Kotlin 2.1.20-RC</a>.</p>
<p>For more details, please refer to the <a href="https://github.com/JetBrains/kotlin/releases/tag/v2.1.20-RC2">changelog</a> or <a href="whatsnew-eap.md">What's new in Kotlin 2.1.20-RC2</a>.</p>
</td>
</tr>
</table>
148 changes: 136 additions & 12 deletions docs/topics/whatsnew-eap.md
View file
Original file line number Diff line number Diff line change
Expand Up @@ -15,10 +15,9 @@ Here are some details of this EAP release:
* [](#kotlin-k2-compiler-new-default-kapt-plugin)
* [](#kotlin-multiplatform-new-dsl-to-replace-gradle-s-application-plugin)
* [](#kotlin-native-new-inlining-optimization)
* [Kotlin/Wasm: migration to Provider API](#kotlin-wasm-migration-to-provider-api-for-kotlin-wasm-and-kotlin-js-properties)
* [Gradle: support for custom publication variants](#support-for-adding-custom-gradle-publication-variants)
* [](#common-atomic-types)
* [](#changes-in-uuid-parsing-and-formatting-functions)
* [Kotlin/Wasm: default custom formatters and migration to Provider API](#kotlin-wasm)
* [Gradle: support for Gradle 8.11, compatibility with Isolated Projects, and custom publication variants](#support-for-adding-custom-gradle-publication-variants)
* [Standard library: common atomic types, improved UUID support, and new time tracking functionality](#standard-library)
* [](#compose-compiler-source-information-included-by-default)

## IDE support
Expand All @@ -30,7 +29,6 @@ All you need to do is to [change the Kotlin version](configure-build-for-eap.md)
See [Update to a new release](releases.md#update-to-a-new-kotlin-version) for details.

## Kotlin K2 compiler: new default kapt plugin

<primary-label ref="beta"/>

Starting with Kotlin %kotlinEapVersion%, the K2 implementation of the kapt compiler plugin is enabled by default
Expand All @@ -52,7 +50,6 @@ kapt.use.k2=false
Please report any issues to our [issue tracker](https://youtrack.jetbrains.com/issue/KT-71439/K2-kapt-feedback).

## Kotlin Multiplatform: new DSL to replace Gradle's Application plugin

<primary-label ref="experimental-opt-in"/>

Starting with Gradle 8.7, the [Application](https://docs.gradle.org/current/userguide/application_plugin.html) plugin is
Expand Down Expand Up @@ -126,7 +123,43 @@ gives an overall performance improvement of 9.5%. Of course, you can try out oth
If you experience increased binary size or compilation time, please report such issues
in [YouTrack](https://kotl.in/issue).

## Kotlin/Wasm: migration to Provider API for Kotlin/Wasm and Kotlin/JS properties
## Kotlin/Wasm

### Custom formatters enabled by default

Before, you had to [manually configure](whatsnew21.md#improved-debugging-experience-for-kotlin-wasm) custom formatters
to improve debugging in web browsers when working with Kotlin/Wasm code.

In this release, custom formatters are enabled by default in development builds, so no additional Gradle configuration
is needed.

To use this feature, you only need to ensure that custom formatters are enabled in your browser's developer tools:

* In Chrome DevTools, it's available via **Settings | Preferences | Console**:

![Enable custom formatters in Chrome](wasm-custom-formatters-chrome.png){width=400}

* In Firefox DevTools, it's available via **Settings | Advanced settings**:

![Enable custom formatters in Firefox](wasm-custom-formatters-firefox.png){width=400}

This change primarily affects development builds. If you have specific requirements for production builds,
you need to adjust your Gradle configuration accordingly. Add the following compiler option to the `wasmJs {}` block:

```kotlin
// build.gradle.kts
kotlin {
wasmJs {
// ...

compilerOptions {
freeCompilerArgs.add("-Xwasm-debugger-custom-formatters")
}
}
}
```

### Migration to Provider API for Kotlin/Wasm and Kotlin/JS properties

Previously, properties in Kotlin/Wasm and Kotlin/JS extensions were mutable (`var`) and assigned directly in build
scripts:
Expand Down Expand Up @@ -172,6 +205,36 @@ must update property assignments to use the `.set()` function.
### Support for version 8.11
Kotlin %kotlinEapVersion% is now compatible with the latest stable Gradle version, 8.11, and supports its features.

### Kotlin Gradle plugin compatible with Gradle's Isolated Projects
<primary-label ref="experimental-opt-in"/>

> This feature is currently in a pre-Alpha state in Gradle.
> Use it only with Gradle version 8.10 or higher and solely for evaluation purposes.
>
{style="warning"}

Since Kotlin 2.1.0, you've been able to [preview Gradle's Isolated Projects feature](whatsnew21.md#preview-gradle-s-isolated-projects-in-kotlin-multiplatform)
in your projects.

Previously, you had to configure the Kotlin Gradle plugin to make your project compatible with the Isolated Projects
feature before you could try it out. In Kotlin %kotlinEapVersion%, this additional step is no longer necessary.

Now, to enable the Isolated Projects feature, you only need to [set the system property](https://docs.gradle.org/current/userguide/isolated_projects.html#how_do_i_use_it).

Gradle’s Isolated Projects feature is supported in Kotlin Gradle plugins for both multiplatform projects and projects
that contain only the JVM or Android target.

Specifically for multiplatform projects, if you notice problems with your Gradle build after upgrading, you can opt out
of the new Kotlin Gradle plugin behavior by setting:

```none
kotlin.kmp.isolated-projects.support=disable
```

However, if you use this Gradle property in your multiplatform project, you can't use the Isolated Projects feature.

We would appreciate your feedback on this feature in [YouTrack](https://youtrack.jetbrains.com/issue/KT-57279/Support-Gradle-Project-Isolation-Feature-for-Kotlin-Multiplatform).

### Support for adding custom Gradle publication variants
<primary-label ref="experimental-opt-in"/>

Expand All @@ -182,9 +245,8 @@ This feature is available for multiplatform projects and projects targeting the
>
{style="note"}

This feature is [Experimental](components-stability.md#stability-levels-explained). To opt in,
use the `@OptIn(ExperimentalKotlinGradlePluginApi::class)` annotation or the compiler option
`-opt-in=kotlin.ExperimentalKotlinGradlePluginApi`.
This feature is [Experimental](components-stability.md#stability-levels-explained).
To opt in, use the `@OptIn(ExperimentalKotlinGradlePluginApi::class)` annotation.

To add a custom Gradle publication variant, invoke the `adhocSoftwareComponent()` function, which returns an instance
of [`AdhocComponentWithVariants`](https://docs.gradle.org/current/javadoc/org/gradle/api/component/AdhocComponentWithVariants.html)
Expand Down Expand Up @@ -291,7 +353,7 @@ fun main() {
```
{validate="false" kotlin-runnable="true" kotlin-min-compiler-version="2.1.20"}

### Changes in UUID parsing and formatting functions
### Changes in UUID parsing, formatting, and comparability
<primary-label ref="experimental-opt-in"/>

The JetBrains team continues to improve the support for UUIDs [introduced to the standard library in 2.0.20](whatsnew2020.md#support-for-uuids-in-the-common-kotlin-standard-library).
Expand All @@ -309,8 +371,13 @@ and [`toHexString()`](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin.uuid/
introduced earlier for the hexadecimal format. Explicit naming for parsing and formatting functionality should improve
code clarity and your overall experience with UUIDs.

UUIDs in Kotlin are now `Comparable`. Starting with Kotlin %kotlinEapVersion%, you can directly compare and sort values
of the `Uuid` type. This enables the use of the `<` and `>` operators, standard library extensions available exclusively
for `Comparable` types or their collections (such as `sorted()`), and allows passing UUIDs to any functions or APIs that
require the `Comparable` interface.

Remember that the UUID support in the standard library is still [Experimental](components-stability.md#stability-levels-explained).
To opt in, use the `@ExperimentalUuidApi` annotation or the compiler option `-opt-in=kotlin.uuid.ExperimentalUuidApi`:
To opt in, use the `@OptIn(ExperimentalUuidApi::class)` annotation or the compiler option `-opt-in=kotlin.uuid.ExperimentalUuidApi`:

```kotlin
import kotlin.uuid.ExperimentalUuidApi
Expand All @@ -327,11 +394,68 @@ fun main() {

// Outputs the UUID in the hex-and-dash format
println(hexDashFormat)

// Outputs UUIDs in ascending order
println(
listOf(
uuid,
Uuid.parse("780e8400e29b41d4a716446655440005"),
Uuid.parse("5ab88400e29b41d4a716446655440076")
).sorted()
)
}
//sampleEnd
```
{validate="false" kotlin-runnable="true" kotlin-min-compiler-version="2.1.20"}

### New time tracking functionality
<primary-label ref="experimental-opt-in"/>

Starting with Kotlin %kotlinEapVersion%, the standard library provides the ability to represent a moment in time.
This functionality was previously only available in [`kotlinx-datetime`](https://kotlinlang.org/api/kotlinx-datetime/),
an official Kotlin library.

The [kotlinx.datetime.Clock](https://kotlinlang.org/api/kotlinx-datetime/kotlinx-datetime/kotlinx.datetime/-clock/)
interface is introduced to the standard library as `kotlin.time.Clock` and the [`kotlinx.datetime.Instant`](https://kotlinlang.org/api/kotlinx-datetime/kotlinx-datetime/kotlinx.datetime/-instant/)
class as `kotlin.time.Instant`. These concepts naturally align with the `time` package in the standard library because
they’re only concerned with moments in time compared to a more complex calendar and timezone functionality that remains
in `kotlinx-datetime`.

`Instant` and `Clock` are useful when you need precise time tracking without considering time zones or dates.
For example, you can use them to log events with timestamps, measure durations between two points in time,
and obtain the current moment for system processes.

To provide interoperability with other languages, additional converter functions are available:

* `.toKotlinInstant()` converts a time value to a `kotlin.time.Instant` instance.
* `.toJavaInstant()` converts the `kotlin.time.Instant` value to a `java.time.Instant` value.
* `Instant.toJSDate()` converts the `kotlin.time.Instant` value to an instance of the JS `Date` class. This conversion
is not precise, JS uses millisecond precision to represent dates, while Kotlin allows for nanosecond resolution.

The new time features of the standard library are still [Experimental](components-stability.md#stability-levels-explained).
To opt in, use the `@OptIn(ExperimentalTime::class)` annotation:

```kotlin
import kotlin.time.*

@OptIn(ExperimentalTime::class)
fun main() {

// Get the current moment in time
val currentInstant = Clock.System.now()
println("Current time: $currentInstant")

// Find the difference between two moments in time
val pastInstant = Instant.parse("2023-01-01T00:00:00Z")
val duration = currentInstant - pastInstant

println("Time elapsed since 2023-01-01: $duration")
}
```
{validate="false" kotlin-runnable="true" kotlin-min-compiler-version="2.1.20"}

For more information on the implementation, see this [KEEP proposal](https://github.com/Kotlin/KEEP/pull/387/files).

## Compose compiler: source information included by default

The Compose compiler Gradle plugin enables [including source information](https://kotlinlang.org/api/kotlin-gradle-plugin/compose-compiler-gradle-plugin/org.jetbrains.kotlin.compose.compiler.gradle/-compose-compiler-gradle-plugin-extension/include-source-information.html)
Expand Down
4 changes: 2 additions & 2 deletions docs/v.list
View file
Original file line number Diff line number Diff line change
Expand Up @@ -13,8 +13,8 @@
<var name="apiVersion" value="2.1" type="string"/>

<!-- Kotlin EAP -->
<var name="kotlinEapVersion" value="2.1.20-RC" type="string"/>
<var name="kotlinEapReleaseDate" value="February 19, 2025" type="string"/>
<var name="kotlinEapVersion" value="2.1.20-RC2" type="string"/>
<var name="kotlinEapReleaseDate" value="March 6, 2025" type="string"/>

<!-- Libraries and Frameworks -->
<var name="coroutinesVersion" value="1.10.1" type="string"/>
Expand Down

0 comments on commit e5aa8ec

Please sign in to comment.