IntelliJ Scala Plugin 2020.1: Scala 3, Function Literal Highlighting, Unused Parameter Inspection, Smart Step Into, and BSP Support Improvements
While the key feature of the 2020.1 Scala plugin release is, of course, Scala 3 support, there are many features and improvements for all versions of Scala. Let’s take a closer look.
Scala 3 support
Now that Dotty is destined to become Scala 3, we have started to work on full-fledged Scala 3 support. The Scala plugin now includes preliminary support for Scala 3: the new syntax, error highlighting, navigation, type info, and many other bread-and-butter IDE features:
Because both the language and the language support are still works in progress, we recommend using plugin nightly builds if you want to get new features and bug fixes as quickly as possible. You can use Settings | Languages | Scala | Update channels to switch to nightly builds (and you can revert to a more stable build at any time):
To try Scala 3, you can either create a new project via File | New | Project | Scala | Dotty, or clone the Dotty example project and open it in IntelliJ IDEA. If you have any questions about Scala 3 support, feel free to ask them in our Gitter.
Fine-grained error highlighting for function literals
Functional literals are used a lot in Scala. They are very similar to methods, and like methods they have separate parameters and bodies. But they are often treated as a single expression of function type, making it harder to locate and interpret errors:
In this release, we’ve introduced fine-grained error highlighting for function literals, which can help you pinpoint errors relying on clear and precise messages, instead of possibly obscure messages with function types.
Unused Parameter inspection
The Scala plugin has been able to show unused variables and methods for a long time. Now it can also spot unused parameters. Parameters that are not referenced inside a method or class are highlighted in gray:
In contrast to variables and methods, unused parameters are often the result of programming errors. So not only does this new inspection make your code cleaner, but it can also help you prevent errors.
Smart Step Into
In Scala, we often have multiple method calls on the same line. In such cases, using Step Into in the debugger is hardly convenient – you have to manually step into and then out of many methods before you reach the desired one.
In this release, Step Into has become Smart Step Into. You can simply choose a desired method, and the IDE will do the work:
BSP support improvements
We’ve improved BSP support. It now works more smoothly and with more projects and build tools. You no longer have to manually install Bloop to import sbt projects via BSP – the Scala plugin can convert such projects to Bloop format automatically. It’s now possible to cancel BSP builds from the Build tool window. Finally, you can view and manage BSP connections using the BSP widget:
There are many more improvements that are not included in this blog post but are included in the release. They make the plugin more polished and more pleasant to work with.
We would like to thank all contributors who helped us to make the Scala plugin better, namely: Krzysztof Romanowski, Tomasz Pasternak, Łukasz Wawrzyk, Ólafur Páll Geirsson, Ciprian Ciubotariu, Arseniy Pendryak, Andrei Ivanyuk, Wiem Zine El Abidine, and others.
The IntelliJ Scala plugin team
IntelliJ Scala Plugin 2023.3 Is Out!
Scala 3 As usual, the new release focused much on improving the Scala 3 support. Especially enums received much attention. The Scala plugin now recognizes that enums cannot be extended and highlights such attempts; annotations and modifiers are now propagated correctly to generated symbols; type…
IntelliJScala @ Scala Days 2023 Madrid
On September 12 – 14, the Scala Plugin team was in Madrid for the Scala Days conference. JetBrains was a Gold Sponsor for the event and we are very proud of it. We came to Madrid with a booth, merchandise, and a talk about the IntelliJ Scala Plugin. The Scala Plugin has seen a lot of improvements…
IntelliJ Scala Plugin 2023.2 Is Out!
Better Scala 3 Support IntelliJ IDEA 2023.2 brings enhanced Scala 3 support, with a focus on providing a streamlined development experience. Notable improvements include fixes for Scala 3 enum highlighting, navigation to enum definitions, and the correct resolution of enum cases in various contex…
IntelliJ Scala Plugin 2023.1 Is Out!
Improved support for braceless Scala syntax IntelliJ IDEA can now desugar braceless Scala code properly, and it handles refactorings where the “fewer braces” feature is used. It also supports braceless syntax in worksheets and correctly interprets indentation when you move extensions methods up a…