Metals Blog http://scalameta.org/metals/blog Metals Blog Tue, 07 Apr 2026 00:00:00 GMT https://validator.w3.org/feed/docs/rss2.html https://github.com/jpmonette/feed en <![CDATA[Metals v1.6.7 - Osmium]]> http://scalameta.org/metals/blog/2026/04/07/osmium http://scalameta.org/metals/blog/2026/04/07/osmium Tue, 07 Apr 2026 00:00:00 GMT We're happy to announce the release of Metals v1.6.7, which mostly focuses on bugfixes and improvements. It also brings long-requested features: automatic decompilation and stdio transport support for the Metals MCP server.

Commits since last release37
Merged PRs37
Contributors9
Closed issues5
New features2

For full details: https://github.com/scalameta/metals/milestone/86?closed=1

Metals is a language server for Scala that works with VS Code, Vim, Emacs, Zed, Helix and Sublime Text. Metals is developed at the Scala Center and VirtusLab with help from contributors in the community.

TL;DR​

Check out https://scalameta.org/metals/, and give Metals a try!

Stdio transport support for the Metals MCP server​

Thanks to majk-p it's now possible to use the Metals MCP server over stdio transport in addition to HTTP transport. This is particularly useful when running agentic tools that do not support per-workspace configuration.

Automatic decoding of .class, .semanticdb, and .tasty files​

When using Visual Studio Code or its forks, Metals can now automatically decode .class, .semanticdb, and .tasty files. Metals registers itself as a separate editor type for these formats, so you can choose Metals when opening a binary file and optionally set it as the default editor for that file type.

This is also controlled by the settings:

"workbench.editorAssociations": {
    "*.class": "metals.classDecoder",
    "*.tasty": "metals.classDecoder",
    "*.semanticdb": "metals.classDecoder"
},

or can be used on a case-by-case basis when opening any of the three supported binary files.

In VS Code, Metals will not be used by default for binary files; you still need to go through "Open anyway" in the dialog, so this change should not affect users who are not interested in decoding these files.

For .class files, you can set the decoder to CFR or javap; CFR is the default.

"metals.classDecoder": "cfr", // also "javap", "javap-verbose", "none"

Miscellaneous​

  • fix(tests): support method call syntax for behavior.of in AnyFlatSpec. nanjo712
  • improvement: Return only last version in find-dep tool instead of all versions. tgodzik
  • Support generating opencode config in metals-mcp. majk-p
  • Add --list-settings flag to print all user configuration options in metals CLI. matejcerny
  • bugfix: Fix potential Metals classpath issue with duplicated AutoImports class tgodzik
  • bugfix: Detect Bazel rules name instead of assuming a name for a specific Bazel version. tgodzik
  • bugfix: Fix an issue with running tests with an empty scalatest prefix tgodzik
  • Better heuristic for guessing the name of the Scala rule set odisseus

Contributors​

Big thanks to everybody who contributed to this release or reported an issue!

$ git shortlog -sn --no-merges v1.6.6..v1.6.7
     18	Tomasz Godzik
     8	dependabot[bot]
     4	scalameta-bot
     2	Michał Pawlik
     1	BrianHotopp
     1	Jiacong Ye
     1	Krzysztof Maliszewski
     1	Matej Cerny
     1	Myroslav

v1.6.7 (2026-04-07)​

Full Changelog

Merged pull requests:

  • improvement: Also add metals v2 methods to RawPresentationCompiler #8289 (tgodzik)
  • build(deps): bump lodash from 4.17.23 to 4.18.1 in /website #8287 (dependabot[bot])
  • build(deps): bump coursier/setup-action from 2 to 3 in the github-actions group #8284 (dependabot[bot])
  • build(deps-dev): bump @types/node from 25.3.3 to 25.5.0 in /website in the npm-dependencies group #8285 (dependabot[bot])
  • chore: Suggest changing metals.macos-max-watch-roots #8283 (tgodzik)
  • chore: Test Metals with Scala 3.8.3 #8211 (tgodzik)
  • build(deps): bump brace-expansion from 1.1.12 to 1.1.13 in /website #8281 (dependabot[bot])
  • build(deps): bump node-forge from 1.3.2 to 1.4.0 in /website #8282 (dependabot[bot])
  • Better heuristic for guessing the name of the Scala rule set #8270 (odisseus)
  • bugfix: Fix constructing invalid symbol #8277 (tgodzik)
  • docs: add jarchive to Emacs setup for dependency source navigation #8280 (BrianHotopp)
  • build(deps): bump picomatch from 2.3.1 to 2.3.2 in /website #8278 (dependabot[bot])
  • feature: Add a tool to return contents of a specific class #8250 (tgodzik)
  • feat: Add stdio transport support for Metals MCP server #8266 (majk-p)
  • bugfix: Fix an issue with an empty scalatest prefix #8274 (tgodzik)
  • docs: Add AGENTS.md file #8275 (tgodzik)
  • bugfix: Detect rules name instead of assuming a specific version #8265 (tgodzik)
  • bugfix: Fix potential issue with duplicated AutoImports class #8264 (tgodzik)
  • Add --list-settings flag to print all user configuration options #8260 (matejcerny)
  • build(deps): bump undici from 6.23.0 to 6.24.1 in /website #8262 (dependabot[bot])
  • chore: Add new config options to presentation compiler conf #8258 (tgodzik)
  • Support generating opencode config in metals-mcp #8247 (majk-p)
  • improvement: Return only last version in find-dep tool #8249 (tgodzik)
  • fix(tests): support method call syntax for behavior.of in AnyFlatSpec #8248 (nanjo712)
  • build(deps): Update scribe, scribe-file, scribe-slf4j2 from 3.17.0 to 3.18.0 #8244 (scalameta-bot)
  • build(deps): Update mill-contrib-testng from 1.1.2 to 1.1.3 #8243 (scalameta-bot)
  • build(deps): Update munit from 1.2.3 to 1.2.4 #8245 (scalameta-bot)
  • build(deps): Update cli_3, scala-cli-bsp from 1.12.3 to 1.12.4 #8246 (scalameta-bot)
  • docs: simplify install instructions #8240 (kmaliszewski9)
  • bugfix: Default to 0 if minor or patch are missing, log warning #8232 (tgodzik)
  • improvement: Add relevant methods from Metals v2 #8238 (tgodzik)
  • improvement: Log which symbols we wanted to insert #8234 (tgodzik)
  • improvement: Fix flakiness with the fatal warnings tests #8233 (tgodzik)
  • build(deps): bump svgo from 3.3.2 to 3.3.3 in /website #8230 (dependabot[bot])
  • docs: Simplify install instructions #8227 (tgodzik)
  • docs: Update docs #8226 (tgodzik)
  • docs: Add release notes for Metals 1.6.6 #8218 (tgodzik)
]]> <![CDATA[Metals v1.6.6 - Osmium]]> http://scalameta.org/metals/blog/2026/03/03/osmium http://scalameta.org/metals/blog/2026/03/03/osmium Tue, 03 Mar 2026 00:00:00 GMT We're happy to announce the release of Metals v1.6.6, which brings a standalone MCP server for AI-powered workflows, support for Play's Twirl templates, easier access to compiler explain output, and an option to shut down the build server when closing your editor.

Commits since last release72
Merged PRs72
Contributors8
Closed issues14
New features5

For full details: https://github.com/scalameta/metals/milestone/85?closed=1

Metals is a language server for Scala that works with VS Code, Cursor, Vim, Emacs, Zed, Helix and Sublime Text. Metals is developed at the Scala Center and VirtusLab with the help from contributors from the community.

TL;DR​

Check out https://scalameta.org/metals/, and give Metals a try!

Allow users to get the output of -explain​

When the Scala compiler suggests using the -explain option to get more detailed error messages, it isn't exactly easy to do so. You would have to change your build configuration, which might require rebuilding the entire project.

Metals now offers two ways to access explain output:

  • With virtual documents support: When your editor supports virtual documents, Metals replaces the code description with a link that invokes a command to get diagnostics from the presentation compiler with -explain enabled.

explain-diagnostic

  • Without virtual documents: If your editor doesn't support virtual documents, Metals shows a code action that, when invoked, creates a new document in the .metals/explained-diagnostics directory with the full diagnostic output from -explain. Some editors might not open the new file automatically.

explain-diagnostic2

Standalone MCP server​

Metals now includes a standalone MCP (Model Context Protocol) server that can run independently of your editor. This allows AI-powered tools like Cursor, Claude Code, or other MCP clients to interact with your Scala project without needing the full Metals language server running inside an IDE.

The standalone server runs over HTTP and automatically imports the workspace when a project is detected. Several improvements make it easier to configure:

A standalone MCP (Model Context Protocol) server for Scala projects.

Usage:
  metals-mcp --workspace <path> [options]

Options:
  --workspace <path>      Path to the Scala project (required)
  --port <number>         HTTP port to listen on (default: auto-assign)
  --transport <type>      Transport type: http (default) or stdio (reserved for future use)
  --client <name>         Client to generate config for: Visual Studio Code, Visual Studio Code - Insiders, VSCodium, vscode, VSCodium - Insiders, Kilo, kilo, Cursor, cursor, claude, Claude Code, claude-code
  --<key> [value]         UserConfiguration override. Use kebab-case (e.g. --java-home /path, --bloop-version 1.4.0).
                          For boolean options, value is optional: omit for true, or use --key true/false.
  --help, -h              Show this help message
  --version, -v           Show version information

Examples:
  # Start MCP server for a project
  metals-mcp --workspace /path/to/project

  # Start with specific port
  metals-mcp --workspace /path/to/project --port 8080

  # Override Java home and enable default BSP to build tool (boolean, omit = true)
  metals-mcp --workspace /path/to/project --java-home /path/to/jdk --default-bsp-to-build-tool

  # Generate config for Cursor editor
  metals-mcp --workspace /path/to/project --client Cursor

  • Client configuration: When you specify --client (e.g. --client cursor), Metals generates the appropriate MCP configuration for supported clients, making setup straightforward for command-line tools.
  • User configuration in CLI: You can pass Metals configuration options directly via the command line using --<key> <value> syntax, including nested keys and boolean flags. This lets you customize the MCP server behavior independently of your editor.

You should be able to install the standalone MCP server using Coursier:

cs install metals-mcp

or Homebrew:

brew install metals

Add an option to shutdown Bloop build server​

A long-standing request was to terminate the Bloop process when closing the editor, so you don't end up with leftover build server processes running in the background if you didn't need it anymore.

Metals now provides the build-disconnect-and-shutdown LSP command. When invoked, it disconnects from the build server and shuts it down so the process exits. Visual Studio Code will use this command if you set the metals.shutdownBloopOnEditorClose configuration option to true. It will try to track the number of open VS Code instances and only exit if there are no more open instances.

It's important to note that this doesn't work with any other BSP server other than Bloop.

Thanks to thomasGuerin3 for implementing this feature!

Support for Play's Twirl templates​

Metals now has LSP support for Play Framework's Twirl template files (.scala.html, .scala.txt, .scala.xml, .scala.js). This work was done as part of Google Summer of Code 2025.

The IDE features for Twirl templates include:

  • Hover: See documentation and type information when hovering over symbols
  • Completions: Get code completions for Scala expressions within templates
  • Go to definition: Navigate from template code to Scala definitions
  • Auto-import: Automatically add imports when using completions
  • Rename: Rename symbols with proper updates across the template
  • Document highlighting: See all occurrences of the symbol currently under the cursor in a single file

twirl

Metals compiles Twirl templates in-memory and maps positions between the template source and the generated Scala code, so all these features should work correctly within the template syntax.

Thanks to ajafri2001 for implementing this feature and to zielinsky for finishing the work!

New File Improvements​

When using "New Scala File" or "New Java File" commands, Metals will now automatically strip extensions from the file name if they are provided. Additionally, there is a new type of new file which will take the current copied snippet and insert it into the new file with the suggested name.

new-file

As this requires access to the clipboard, it's only available in the Visual Studio Code extension, which implements the new clipboard API.

Miscellaneous​

  • fix: reduce presentation compiler memory usage (#6967) krrish175-byte
  • improvement: Properly set minimum Bloop version instead of using newest to avoid unnecessary bloop server restart messages tgodzik
  • feat(mcp): Add smart fallback and module parameter for inspect, get-docs, get-usages li-nkSN
  • fix: Recompile worksheet on changes even if didFocus is not supported krrish175-byte
  • improvement: Add message on timeouts to simplify debugging for users tgodzik
  • bugfix: Make sure that cs or coursier is a coursier binary tgodzik
  • improvement: Add KiloCodeEditor client configuration cheleb

Contributors​

Big thanks to everybody who contributed to this release or reported an issue!

$ git shortlog -sn --no-merges v1.6.5..v1.6.6
    28	scalameta-bot
    23	Tomasz Godzik
     7	dependabot[bot]
     2	Krrish Biswas
     1	Olivier NOUGUIER
     1	Prince
     1	li-nkSN
     1	thomasGuerin3

Merged PRs​

v1.6.6 (2026-02-27)​

Full Changelog

Merged pull requests:

]]> <![CDATA[Metals v1.6.5 - Osmium]]> http://scalameta.org/metals/blog/2026/01/21/osmium http://scalameta.org/metals/blog/2026/01/21/osmium Wed, 21 Jan 2026 00:00:00 GMT We're happy to announce the release of Metals v1.6.5, which brings several exciting new features including completions for implicit classes, auto imports for Java, Type Hierarchy support, and an updated MCP server implementation.

Commits since last release110
Merged PRs110
Contributors16
Closed issues43
New features3

For full details: https://github.com/scalameta/metals/milestone/84?closed=1

Metals is a language server for Scala that works with VS Code, Vim, Emacs, Zed, Helix and Sublime Text. Metals is developed at the Scala Center and VirtusLab with the help from contributors from the community.

TL;DR​

Check out https://scalameta.org/metals/, and give Metals a try!

Completions for implicit classes​

Metals can now suggest methods from implicit classes that are not yet imported in your code. When you type a method that could come from an implicit class in your workspace or dependencies, Metals will show these completions with an (implicit) label and automatically add the necessary import when you accept the completion.

For example, if you want to use the millisecond method from scala.concurrent.duration package, typing 2.mill will now suggest millisecond from DurationInt and add import scala.concurrent.duration.DurationInt when selected. This also works for implicit classes defined in your own workspace - if you define implicit class MyIntOps(n: Int) with a myDouble method, you can use it anywhere in your project and Metals will handle the import automatically.

Thanks to pielas for implementing this feature!

Add auto imports for Java​

Metals now supports auto imports for Java files! When you use a class that isn't imported yet, Metals will suggest the import and automatically add it for you when you accept the completion. Metals won't add duplicate imports and properly handles wildcard imports (e.g., java.util.*). If there's a naming conflict with an existing import, Metals will insert the fully qualified class name instead.

Thanks to zielinsky for working on this!

Switch to streamable HTTP standard​

The Metals MCP server has been updated to use the new streamable HTTP transport standard. This change brings the MCP implementation in line with the latest MCP specification and improves compatibility with various MCP clients.

What changed: The MCP server endpoint has been changed from /sse (Server-Sent Events) to /mcp. For some users with common editors like Cursor, VS Code, or Claude, Metals will automatically rewrite your existing configuration to use the new endpoint when you start the MCP server.

Manual migration: If you have a custom MCP client configurations, you'll need to update the URL from http://localhost:<port>/sse to http://localhost:<port>/mcp. Metals will attempt to detect and update configurations automatically, but if you maintain your own setup, please update accordingly.

Implement Type Hierarchy support​

Metals now supports the LSP Type Hierarchy feature, allowing you to explore class inheritance relationships directly from your editor. This feature provides three capabilities:

  • Prepare Type Hierarchy: When you place your cursor on a class, trait, object, or type, you can request to see its type hierarchy.
  • Supertypes: Navigate upward in the inheritance tree to see parent classes and implemented traits. For example, selecting Dog will show you Animal and AnyRef if Dog extends Animal.
  • Subtypes: Navigate downward to discover all classes that extend or implement the selected type.

This feature works across your entire project, including dependencies stored in JAR files. The type hierarchy information is indexed and stored in a database for fast lookups.

To use this feature, look for "Show Type Hierarchy" or similar commands in your editor (the exact UI depends on your editor's LSP support).

Thanks to warcholjakub for implementing this feature!

Incoming Metals 2​

We are currently testing and working on new Metals 2, which is a major overhaul of how Metals works. The main intention is to make it much better for larger monorepo setups as well as improve user experience even if your codebase is not compiling.

Take a look at the new Metals 2 website for more information.

We don not have a release date yet, but we want to make sure that all the features available in Metals 1 are available in Metals 2.

Miscellaneous​

  • bugfix: Filter out invalid multiline comment fold ranges (discapes)
  • bugfix: Correct autoImportBuilds config key name (jklukas)
  • improvement: Support build.mill.yaml build files lolgab
  • bugfix:Fix script definition URIs to point to original .sc files (zielinsky)
  • improvement: Use mill scripts if available in the workspace (tgodzik)
  • improvement: Support inspecting Java generic types in MCP (warcholjakub)
  • bugfix: SQL syntax highlighting in complex cases (warcholjakub)
  • bugfix: Fix SQL highlighting for nested interpolators #8047 (Mensh1kov)
  • improvement:Make Metals look for ./mill and ./mill.bat files when identifying Mill projects lihaoyi
  • improvement: Show a warning when newer -release version flag is used (tgodzik)
  • bugfix: ZIO test explorer reveals sub-tasks with provideLayer (krrish175-byte)
  • improvement: Add memory usage warning when heap is nearly full (krrish175-byte)
  • bugfix: Inline value false-positive shadowing with lambda params (krrish175-byte)
  • Fix: Handle InvalidSymbolException in StacktraceAnalyzer (#7974) (krrish175-byte)
  • improvement: Use jar based coursier as a fallback when not available in PATH (tgodzik)
  • improvement: Compile only JVM targets by default when not focusing on Native and JS specific files. (warcholjakub)
  • improvement: Forward credentials to Bloop process (krrish175-byte)
  • bugfix: Fix inlining interpolated variables #8108 (johndoknjas)
  • bugfix: Fix MCP server identification for multi-project workspaces (krrish175-byte)

Contributors​

Big thanks to everybody who contributed to this release or reported an issue!

$ git shortlog -sn --no-merges v1.6.4..v1.6.5
    42 scalameta-bot
    33 Tomasz Godzik
    12 dependabot[bot]
     4 Jakub Warchoł
     7 Krrish Biswas
     2 Jeff Klukas
     2 Zieliński Patryk
     1 John Doknjas
     1 Jonathan Burns
     1 Li Haoyi
     1 Lorenzo Gabriele
     1 Mateusz Piękos
     1 Mensh1kov
     1 Miika Tuominen
     1 Russ White

Merged PRs​

v1.6.5 (2026-01-20)​

Full Changelog

Merged pull requests:

]]> <![CDATA[Metals v1.6.4 - Osmium]]> http://scalameta.org/metals/blog/2025/11/25/osmium http://scalameta.org/metals/blog/2025/11/25/osmium Tue, 25 Nov 2025 00:00:00 GMT We're happy to announce the release of Metals v1.6.4, which brings in a number of improvements for Java support as well as some bugfixes and improvements for other features.

Commits since last release46
Merged PRs46
Contributors7
Closed issues23
New features8

For full details: https://github.com/scalameta/metals/milestone/83?closed=1

Metals is a language server for Scala that works with VS Code, Vim, Emacs, Zed, Helix and Sublime Text. Metals is developed at the Scala Center and VirtusLab with the help from contributors from the community.

TL;DR​

Check out https://scalameta.org/metals/, and give Metals a try!

Java support improvements​

Some basic Java support was already added in an earlier version of Metals, but since then we haven't improved it too much. However, it came to our attention that there is plenty of codebases that currently use Bazel and a mixture of Scala and Java. For those codebases there is no way to use LSP properly aside from Metals. We decided to improve some lower hanging fruits when it comes to Java support.

These new features include:

  • Navigating to definition will now be using the Java compiler directly first, which will not require a full compilation of the file.
  • Signature help for methods and constructors in Java files will now show up together with the documentation.
  • Document highlight for Java will now also be using the compiler instead of semanticdb.
  • Rename and references using the Java compiler directly for variables and methods that are not accessible from other files.

All those improvements allow users to work with Java files without having to compile them first to access most important features.

If there is a feature that you feel is missing, please let us know by opening an issue on GitHub.

We still plan on working on auto import functionality and overall improvements for Java support in the near future.

Save configuration that was run via lenses to Vs Code launch.json​

Previously, when running a configuration that was run via code lenses, we would not save that configuration anywhere and the user would have to manually save it to the launch.json file. Now, when running main classes via lenses, we will save that configuration for main classes to the launch.json file automatically if the configuration is not already present.

This behaviour is already present in some other IDEs, so this should be a welcome improvement for many users.

Produce diagnostics for errors in sbt files​

When importing a sbt project with the default settings, Metals would not produce any diagnostics for errors in sbt files even if the import failed. This would cause confusion for users as they would not know why the import failed unless they dug through the log files.

In this release, thanks to the work of @afentev, Metals will show the errors in the problem tab alongside other diagnostics.

Refactoring: Automatically add imports when copying between files​

This feature was add to the last version of metals, but unfortunately it turned out to not be working correctly yet. In this release, we improved it to reuse the existing auto import functionality when copying between files, which is much more robust and reliable.

Additionally, the feature will now also work for Scala 3 files in the upcoming 3.8.0 and 3.3.8 versions of Scala. 3.8.0-RC1 is already available for testing.

Add fallback for showMessageRequest​

Some editors, such as Helix, do not support the showMessageRequest method, which is required for the Metals to work properly. To allow them to function correctly, we added a fallback with a default option to choose in each show message request.

This can be enabled by adding the following to the Metals server configuration in the user settings:

-Dmetals.disable-show-message-request=true

or configuring the client to be Helix editor via:

-Dmetals.client=helix

Let us know if any functionality is missing or is still not working as expected.

Miscellaneous​

  • bugfix: Increase timeout for starting tests and make it configurable zielinsky
  • improvement: Also clear caches in case of 2.12 issues tgodzik
  • bugfix: Don't show sbt warnings as errors after Bloop import tgodzik
  • improvement: Include constructor params in document symbol tgodzik
  • bugfix: Support standard Scala 3 library when capture checked tgodzik
  • Cancel compilation before cleaning up the workspace pielas
  • bugfix:Fixed issues when using repositories with credentials tgodzik
  • improvement: Offer to regenerate Scala CLI config when clicking on build tool status tgodzik
  • improvement: Allow first letter to be lower case even if the variable name start with a capital letter tgodzik
  • Allow configuring preferred build system in user config jklukas
  • bugfix: Use existing auto import functionality instead of custom one when copying between files tgodzik
  • bugfix: Add repl module for Scala 3.8.0 in worksheets tgodzik

Contributors​

Big thanks to everybody who contributed to this release or reported an issue!

$ git shortlog -sn --no-merges v1.6.3..v1.6.4
     38	Tomasz Godzik
     1	Jeff Klukas
     1	Kirill Afentev
     1	Mateusz Piękos
     1	Radek Busz
     1	Zieliński Patryk
     1	dependabot[bot]

Merged PRs​

v1.6.4 (2025-11-21)​

Full Changelog

Merged pull requests:

  • bugfix: Reload classloader when republishing rules #7972 (tgodzik)
  • chore: Don't throw if we can't find symbol #7972 (tgodzik)
  • bugfix: Feature proof support for Scala 3.8.0 #7972 (tgodzik)
  • improvement: Add fallback if showMessageRequest is not supported #7954 (tgodzik)
  • improvement: Ignore flaky tests on MacOS #7968 (tgodzik)
  • add debuggeeGracePeriod as a configuration parameter #7969 (zielinsky)
  • improvement: Also clear caches in case of 2.12 issues #7967 (tgodzik)
  • bugfix: Don't show sbt warnings as errors after import #7966 (tgodzik)
  • improvement: Include constructor params in document symbol #7953 (tgodzik)
  • bugfix: Fix test for the new version of Scala 2.13 #7965 (tgodzik)
  • bugfix: Support standard library when capture checked #7963 (tgodzik)
  • chore: Add support for Scala 2.13.18 #7962 (tgodzik)
  • chore: Update Bloop to 2.0.17 #7960 (tgodzik)
  • Cancelling compilation before cleaning up the workspace #7959 (pielas)
  • feature: Add rename for Java PC #7957 (tgodzik)
  • bugfix: Download fully cross version scalafix dependency #7955 (tgodzik)
  • chore: Remove unused class #7952 (tgodzik)
  • bugfix: Retry downloading scalafix with fallback #7949 (tgodzik)
  • chore: Update scala nightlies repo and remove old sonatype one #7950 (tgodzik)
  • bugfix: Use coursierapi to make sure credentials are used #7947 (tgodzik)
  • bugfix: Check for null in .tpe #7948 (tgodzik)
  • feature: Add support for references in Java PC #7934 (tgodzik)
  • improvement: Also allow using full target id when using discovery #7945 (tgodzik)
  • chore: Update all website dependencies #7942 (tgodzik)
  • build(deps): bump actions/upload-artifact from 4 to 5 #7935 (dependabot[bot])
  • improvement: Offer to regenerate Scala CLI config when clicking on status #7933 (tgodzik)
  • bugfix: Do not throw from OnDemandDefinitionIndex #7931 (tgodzik)
  • chore: Add tests for #5923 #7929 (tgodzik)
  • improvement: Allow first letter to be lower case #7907 (tgodzik)
  • bugfix: Don't modify name if incorrect position #7928 (tgodzik)
  • Allow configuring preferred build system in user config #7924 (jklukas)
  • feat: Produce diagnostics for errors in sbt files #7464 (afentev)
  • feature: Add document highlight for Java using the compiler directly #7927 (tgodzik)
  • improvement: Add stack trace to toplevels fail message #7926 (tgodzik)
  • feature: Add signature help for Java files #7922 (tgodzik)
  • bugfix: Use existing auto import functionality instead #7912 (tgodzik)
  • feature: Add compiler go to definition for Java #7920 (tgodzik)
  • improvement: Do not use imgur for images #7918 (tgodzik)
  • bugfix: Drop suffix when working with scalafix #7915 (tgodzik)
  • bugfix: Fix navigation in mill projects for Java #7914 (tgodzik)
  • bugfix: Remove usage of listFiles, which can cause null pointer exception #7910 (tgodzik)
  • bugfix: Add missing type to array in MCP schema #7905 (gitplaneta)
  • chore: Update scalafmt to 3.10.0 #7906 (tgodzik)
  • bugfix: Fix images in the last releases #7902 (tgodzik)
  • chore: Add release notes for Meals 1.6.3 #7899 (tgodzik)
  • bugfix: Fix test issues after merging #7900 (tgodzik)
]]> <![CDATA[Metals v1.6.3 - Osmium]]> http://scalameta.org/metals/blog/2025/10/16/osmium http://scalameta.org/metals/blog/2025/10/16/osmium Thu, 16 Oct 2025 00:00:00 GMT We're happy to announce the release of Metals v1.6.3, which brings a number of improvements as well as interesting new features. This release has seen a lot of contributions from the community and we would like to thank everyone who helped with this release!

Commits since last release127
Merged PRs127
Contributors18
Closed issues33
New features8

For full details: https://github.com/scalameta/metals/milestone/82?closed=1

Metals is a language server for Scala that works with VS Code, Vim, Emacs, Zed, Helix and Sublime Text. Metals is developed at the Scala Center and VirtusLab with the help from contributors from the community.

TL;DR​

Check out https://scalameta.org/metals/, and give Metals a try!

MCP: Scalafix rule generation​

Metals now provides a new Model Context Protocol tool for generating Scalafix rules within the MCP server. This can be used to run refactorings generated by LLMs on your codebase.

Most of the work around publishing and running Scalafix rules is done by Metals itself, while the LLM is only responsible for generating the rule implementation and description.

This works best on smaller codebases, but can later be published and used in larger ones.

Each rule generated by the MCP server will be saved in the .metals/rules directory and is a self-contained Scala CLI project.

An example query that can be used and has been tested with is:

Using MCP, generate a scalafix rule that will change expressions with filter and map
such as `.filter(x => x > 1).map(x => x * 2)` into collect statements like `.collect{case x if x > 1 => x * 2}`

When used with Claude Code or Cursor (or your MCP-supporting LLM tool of choice), this will generate a finished rule in a few tries at a maximum.

The new tool is still experimental and there might be some rough edges, but we're happy to hear your feedback and suggestions! Some possible errors might involve not validating the inputs from the LLM properly or not returning an actionable enough error message.

Once generated, the rule can be run also using the metals.scalafix-run-only command in the same workspace or published from the rule directory if not already published when generating the rule.

Commands: Add a "copy fqn" command​

Thanks to KacperFKorban we now have a new command that allows to copy the fully qualified name of a symbol to be used in places such as Scaladoc comments.

For example, if you have the following code:

package com.example
object Main {
  def main(args: Array[String]): Unit = {
    println("Hello, world!")
  }
}

You can copy the fully qualified name of the main method to obtain com.example.Main#main.

This command should be available in all editors that support 'workspace/executeCommand' LSP endpoint.

In Visual Studio Code, you can bind this command to a shortcut or invoke it from the dropdown menu with your cursor on the symbol and select Copy reference.

Inlay hints: Add closing labels​

Another great feature added by KacperFKorban is the support for showing closing labels in inlay hints.

When this setting is enabled, each method/class/object definition that uses braces syntax will get a closing label hint next to the closing brace with the name of the definition.

For example:

object Main {
  def main(args: Array[String]): Unit = {
    println("Hello, world!")
  } /*main*/
} /*Main*/

Where /*main*/ and /*Main*/ are the closing labels.

This can be enabled by setting the metals.inlayHints.closingLabels.enable setting.

The feature is currently available only for Scala 2, we are planning to add support for Scala 3 in the near future.

Let us know what you think!

Refactoring: Automatically add imports when copying between files​

In this release, thanks to kasiaMarek there is a new paste command that allows to automatically add imports when copying between files. This command is enabled by default in Scala files within VS Code and requires the origin to be filed when adding in other editors.

paste-import

The change will currently only work for Scala 2, some further work is needed to add support for Scala 3.

Testing: Add cursor-based target discovery for running closest main or test​

Another new code action, added by warcholjakub, is one that allows to run the closest main or test to the cursor.

This new command is available in Visual Studio Code via metals.run-closest in the command palette and can be assigned to a new shortcut.

run-closest

Testing: Test discovery for Bazel​

Up until this release, discovering tests in your Bazel workspace was not supported. This was because Bazel BSP server itself doesn't provide any information about test suites as other build tools and servers are able to.

Metals will now use semanticdb to discover test suites and test cases for Bazel only. This means you need to have semanticdb enabled in your Bazel workspace for this to work.

Thanks to pielas for his great work!

Code actions: Convert infix to normal apply​

Thanks to yoosefi12 we now have a new code action that allows to convert infix apply to normal apply.

This means that whenever you see an infix apply such as:

mystring startsWith "hello"

you can convert it to a normal apply by choosing the correct code action.

mystring.startsWith("hello")

This doesn't apply to infix apply that are symbolic operators, such as '+', '*', etc. which are expected to be infix.

Code actions: Implement Convert to collect code action​

Another new code action added is one that allows to convert filter and map chains into collect statements.

For example with the following code:

List(1, 2, 3, 4).filter(x => x > 2).map(x => x * 2)

you can convert it to a collect statement by invoking the code action.

List(1, 2, 3, 4).collect {
  case x if x > 2 => x * 2
}

Thanks to scarf005 for working on this!

Contributors​

Big thanks to everybody who contributed to this release or reported an issue!

$ git shortlog -sn --no-merges v1.6.2..v1.6.3
    54	Tomasz Godzik
    43	scalameta-bot
     6	Jakub Warchoł
     5	Mateusz Piękos
     2	Alec Theriault
     2	Kacper Korban
     2	Zieliński Patryk
     2	dependabot[bot]
     2	ormaniec
     1	Alexandre Archambault
     1	Ali Yoosefi
     1	Connor Taffe
     1	Jędrzej Rochala
     1	Konrad Gądek
     1	Matt Bovel
     1	Panov Ivan
     1	eugene yokota
     1	scarf

Merged PRs​

v1.6.3 (2025-10-16)​

Full Changelog

Merged pull requests:

]]> <![CDATA[Metals v1.6.2 - Osmium]]> http://scalameta.org/metals/blog/2025/08/09/osmium http://scalameta.org/metals/blog/2025/08/09/osmium Sat, 09 Aug 2025 00:00:00 GMT We're happy to announce the release of Metals v1.6.2, which is mainly a bugfix release.

Commits since last release28
Merged PRs28
Contributors5
Closed issues1
New features0

For full details: https://github.com/scalameta/metals/milestone/81?closed=1

Metals is a language server for Scala that works with VS Code, Vim, Emacs, Zed, Helix and Sublime Text. Metals is developed at the Scala Center and VirtusLab with the help from contributors from the community.

TL;DR​

Check out https://scalameta.org/metals/, and give Metals a try!

Miscellaneous​

  • improvement: Also include SQL interpolation tgodzik
  • bugfix: Remove jrtClassPathCAches to try fix -release issues tgodzik
  • improvement: Enable Scala3Future dialect support (capture checking, better modularity) Odomontois
  • bugfix: Don't show error message when scalafix was invoked from quickfix tgodzik

Contributors​

Big thanks to everybody who contributed to this release or reported an issue!

$ git shortlog -sn --no-merges v1.6.1..v1.6.2
    12	Tomasz Godzik
    11	scalameta-bot
     3	dependabot[bot]
     1	Odomontois
     1	Zieliński Patryk

Merged PRs​

v1.6.2 (2025-08-09)​

Full Changelog

Merged pull requests:

]]> <![CDATA[Metals v1.6.1 - Osmium]]> http://scalameta.org/metals/blog/2025/07/31/osmium http://scalameta.org/metals/blog/2025/07/31/osmium Thu, 31 Jul 2025 00:00:00 GMT We're happy to announce the release of Metals v1.6.1, which further improves MCP support as well as continues to improve the overall stability of using Metals.

Commits since last release91
Merged PRs87
Contributors17
Closed issues27
New features5

For full details: https://github.com/scalameta/metals/milestone/80?closed=1

Metals is a language server for Scala that works with VS Code, Vim, Emacs, Zed, Helix and Sublime Text. Metals is developed at the Scala Center and VirtusLab with the help from contributors from the community.

TL;DR​

Check out https://scalameta.org/metals/, and give Metals a try!

SQL highlighting​

Thanks to Mensh1kov Metals now supports highlighting SQL queries in the editor when sql or fr interpolated strings are used.

sql-highlighting

Model Context Protocol Improvements​

The biggest number of improvements in this release are related to MCP support. This includes both new features and overall quality of life improvements.

New features​

This release includes two new tools. The first one is a tool to list currently available modules, which helps agents to discover what modules are available to use (kasiaMarek). The second one is a tool to format files, which helps agents to format files in a way that is consistent with the project's style (ckipp01).

Quality of life improvements​

Based on feedback from the community, a few quality of life improvements have been added to the MCP tools.

First of all, support for ZIO to the MCP test tool has been added by avshRepo. This allows LLM Agents to run specific tests in ZIO test support. Another improvement in this area is the ability to run specific tests cases added by ckipp01.

Another improvement is related to configuring the MCP server. We now save the MCP server configuration in the workspace settings, so that it's available to all tools that use MCP. This might be useful when connecting to MCP for example multiple LLM tools to use the same port without having to manually configure it.

Moreover, there have been some race conditions when starting Metals in Cursor when the MCP server was not yet ready. We now recreate the MCP server configuration after we are sure that the server is started.

Lastly, this release added support for claude by default again thanks to ckipp01.

For all of you asking to use Metals MCP standalone, there has been some community contributions to make it easier to use Metals MCP standalone. Checkout metals-standalone-client by jpablo for more details.

Updates to fuzzy matcher logic​

There has been a number of reports by users that the previous behaviour of fuzzy matching is too strict and caused some completions to be hidden when the case of the first letter is wrong. This has been fixed by ltrojanowski and the new behaviour is now more forgiving.

You can take a look at the details for more information as well as provide us some further feedback.

New X-ray inlay hints​

Thanks to henryxparker Metals now supports so called X-ray inlay hints that you might know from IntelliJ. When those inlay hints are enabled you will see the type next to a longer chain of expressions. This is particularly useful when you are working with complex expressions and you want to understand exactly what transformations are taking place.

val transformedList =
   List(1, 2, 3)
     .map(x => x * 2)/*     : List[Int]*/
     .map(x => x.toString)/*: List[String]*/
     .map(x => x.length)/*  : List[Int]*/

Try it out by enabling the metals.inlayHints.hintsXRayMode setting. Let us know what you think!

The feature is currently available only for Scala 2, we will add support for Scala 3 in the near future, but it requires a new version of the Scala 3 compiler.

Miscellaneous​

  • bugfix: Run close when stopping the presentation compiler to avoid breaking interactive features in 2.13.x tgodzik
  • improvement: Don't suggest object import in type position tgodzik
  • bugfix: Import object when .type is used tgodzik
  • improvement: Don't ask to restart bloop on Bloop version update tgodzik
  • improvement: Auto detect build target in attach if not specified based on currently focused file tgodzik
  • bugfix: Ignore implicit apply for signature help harpocrates
  • bugfix: Fix completions at the start of the file tgodzik
  • bugfix: Show signature help inside annotation trees harpocrates
  • bugfix: Don't try to find definition for invalid symbols tgodzik
  • improvement: Add an ability to trace mcp requests by creating .metals/mcp.trace.json file tgodzik
  • feature: discover main classes in dependencies when running without debug harpocrates
  • bugfix: pass the environment variables from the BSP server when running tests arturaz
  • improvement: delete old compilation units from pc to reduce memory usage over long sessions kasiaMarek
  • Add support for scala-attach-remote for build servers without in-built DAP support adrien-piquerez-da
  • bugfix: Fix completion before string literal ajafri2001
  • bugfix: Escape $ in shell command tgodzik
  • feature: Use the new fork of Bazel BSP under org.virtuslab.bazel-bsp organization kc-vl
  • feature: Allow users of ZIO test support to run specific suite or suiteAll avshRepo
  • improvement: Add support for running specific tests in scalatest feature specs tmilner
  • bugfix: detect bzl workspace for both WORKSPACE and MODULE.bazel files kc-vl
  • bugfix: Remove stale top level symbols from current run to avoid non existing intermediate symbols with multiple open files tgodzik
  • chore: Don't restart Bloop when properties are uninitialized tgodzik
  • bugfix: Fix missing signature help in superclass constructor zielinsky

Contributors​

Big thanks to everybody who contributed to this release or reported an issue!

$ git shortlog -sn --no-merges v1.6.0..v1.6.1
    30	Tomasz Godzik
    23	scalameta-bot
    11	Katarzyna Marek
     4	Chris Kipp
     4	ajafri2001
     4	dependabot[bot]
     3	Alec Theriault
     2	Avshalom Orenstein
     2	kc-vl
     1	Adrien Piquerez
     1	Artūras Šlajus
     1	Henry Parker
     1	Lukasz Trojanowski
     1	Mensh1kov
     1	Tom Milner
     1	Zieliński Patryk
     1	scarf

Merged PRs​

v1.6.1 (2025-07-31)​

Full Changelog

Merged pull requests:

]]> <![CDATA[Metals v1.6.0 - Osmium]]> http://scalameta.org/metals/blog/2025/06/05/osmium http://scalameta.org/metals/blog/2025/06/05/osmium Thu, 05 Jun 2025 00:00:00 GMT We're happy to announce the release of Metals v1.6.0, which, among other things, fixes a regression from the previous release and adds fixes and improvements to the recently added MCP support.

Commits since last release51
Merged PRs50
Contributors8
Closed issues8
New features2

For full details: https://github.com/scalameta/metals/milestone/79?closed=1

Metals is a language server for Scala that works with VS Code, Vim, Emacs, Zed, Helix and Sublime Text. Metals is developed at the Scala Center and VirtusLab with the help from contributors from the community.

TL;DR​

Check out https://scalameta.org/metals/, and give Metals a try!

MCP improvements and fixes​

Based on user feedback since the previous release, we have fixed some issues related to MCP and added some new tools to further facilitate better agent interaction.

New tools:

  • compile-module - compile a chosen build target, input is the module name, the same as visible in the Metals Doctor.
  • find-dep - completion tool for finding dependencies using Coursier added by tgodzik.

Improvements:

  • MCP port is now saved and reused for the workspace, so it doesn't have to be repeatedly adjusted in other configurations.
  • Better responses in compile tool. Previously it would only return information about issues and an empty result otherwise; now we explicitly mark a successful compilation. Also for file compilation, if no error is found in the file, Metals will return errors from the whole module to provide possibly useful context.

Fixes:

  • inspect for Scala 3 would previously fail and return only the symbol name.
  • verbose flag marked as optional was previously required. Thanks, rtar for the fix.
  • Correctly handle package objects.
  • Fix generating MCP configuration for VSCode alternative distributions (VSCodium and insider versions).

Module status bar​

This release includes a new status bar, which should make some information about the module state more visible.

By default, the status shows the name of the module (build target) that the file in focus belongs to. If the file doesn't belong to any build target or due to an error the build target cannot be resolved, the status will show no build target error message. If the build target is found but there is a compile error in an upstream module, the status will show an error with the name of the upstream module. Finally, if the build target is found and there are no upstream errors, but there are new error reports created for the build target, the status will show a warning with the number of error reports.

Fixed blocking user requests​

In the previous release, a bug was introduced where Metals would sometimes block waiting for the response for user notification. As a result, Import build, Switch build server and similar requests would fail to work. This issue was fixed in this release with an added timeout.

Fixes for backticked identifiers​

This release brings a few fixes around handling backticked identifiers: selection range, location of insert-types code action, and symbol search. Thanks go to harpocrates, who added the needed special handling where it was missed.

Changes for plugin authors​

This release adds a module statusType to metals/status request. Further, it modifies the MetalsStatusParams by adding a new metalsCommand field with the following scheme

{
  "title": "string",
  "command": "string",
  "tooltip": "string | undefined",
  "arguments": "any[] | undefined"
}

metalsCommand field should take precedence over the previously existing command field.

Depending on if the client supports the metals/status extension, the field moduleStatusBarProvider in initialization options should be populated; it can contain one of the following values:

  • on - if client supports metals/status
  • off - if the client doesn't support metals/status
  • show-message - if the client doesn't support metals/status, but would like the module status to be sent via show message request.
  • log-message - if the client doesn't support metals/status, but would like the module status logged. If the field is empty, it defaults to off.

Contributors​

Big thanks to everybody who contributed to this release or reported an issue!

$ git shortlog -sn --no-merges v1.5.3..v1.6.0
    18	Tomasz Godzik
    11	scalameta-bot
    14	Katarzyna Marek
     4	Alec Theriault
     2	dependabot[bot]
     1	Adam Warski
     1	Ruslans Tarasovs

Miscellaneous​

  • fix: indexer bug around type members harpocrates
  • chore: added support for mill 0.12.14 and 1.0.0 tgodzik.
  • fix: encode build target names to include in report file name kasiaMarek
  • fix: use dependency modules for Bazel kasiaMarek
  • improvement: Cache tokenization results when possible tgodzik
  • feat: symbol search for backticked identifiers harpocrates
  • bugfix: Calculate completion items eagerly for Scala 2 tgodzik

Merged PRs​

v1.6.0 (2025-06-05)​

Full Changelog

Merged pull requests:

]]> <![CDATA[Metals v1.5.3 - Strontium]]> http://scalameta.org/metals/blog/2025/05/13/strontium http://scalameta.org/metals/blog/2025/05/13/strontium Tue, 13 May 2025 00:00:00 GMT We're happy to announce the release of Metals v1.5.3, which besides many bugfixes and improvements brings an MCP server implementation to Metals, allowing your AI agent to also use the information that Metals can provide.

Commits since last release135
Merged PRs89
Contributors24
Closed issues32
New features9

For full details: https://github.com/scalameta/metals/milestone/78?closed=1

Metals is a language server for Scala that works with VS Code, Vim, Emacs, Zed, Helix and Sublime Text. Metals is developed at the Scala Center and VirtusLab with the help from contributors from the community.

TL;DR​

Check out https://scalameta.org/metals/, and give Metals a try!

MCP support​

Starting with this release, Metals can serve an SSE, MCP server.

Why?​

AI agents have the tendency to make up the existence of some functions, classes, arguments, and so on. If we allow them to use the information that Metals already has and provide them with such capabilities as searching for symbols, discovering class members, signature help, and getting symbol documentation, we expect AI agents to yield much more relevant suggestions.

Furthermore, giving the AI agent the capability to compile files, run tests, and import builds can further help automate your workflow.

How to use Metals MCP?​

To enable Metals MCP support, set metals.startMcpServer to true. For common editors like Cursor or VSCode (GitHub Copilot), MCP configuration will be automatically added to your workspace. However, you should still check in your AI agent settings that the connection was made successfully. For other AI, Metals will show a message upon MCP server startup with the port on which it was started locally. If you miss it, Metals MCP server started on port: ${port} message is also printed in the Metals log (.metals/metals.log).

Current list of MCP tools:​

  • compile-file -- Compile a chosen Scala file.
  • compile-full -- Compile the whole Scala project.
  • test -- Run Scala test suite.
  • glob-search -- Search for symbols containing substring
  • typed-glob-search -- Search for symbols containing a substring that match the allowed symbol kinds (e.g., class, method).
  • inspect -- Inspect a chosen Scala symbol. For packages, objects, and traits, it returns a list of members; for classes, it returns a list of members and constructors; and for methods, it returns signatures of all overloaded methods.
  • get-docs -- Get documentation for a chosen Scala symbol
  • get-usages -- Get usages for a chosen Scala symbol.
  • import-build -- Import the build to IDE. Should be performed after any build changes, e.g., adding dependencies or any changes in build.sbt.

This feature is still experimental, and we'd love to get your feedback and improvement suggestions.

Best effort compilation​

Best effort compilation was first introduced to Metals v1.3.4 (see here); however, due to multiple issues with it, it was disabled. Since then, a lot was fixed and improved in the area, so this release reintroduces best effort compilation behind a setting; simply set metals.enableBestEffort to true and give it a try.

New inlay hints​

Named parameters​

tgodzik added inlay hints for showing parameters' names on call site. The new inlay hint is available under inlay-hints.named-parameters.enable Metals setting, for now available only for Scala 2.

By-name parameters​

We also have new inlay hints marking by-name parameters with => on the call site. Thanks go to harpocrates.

Remove invalid imports code action​

This release also has a new code action for removing invalid imports, saving you the trouble of deleting them manually. It is yet another improvement added by harpocrates. Code action works both for Scala 2 and Scala 3, though older Scala 2 versions might get only partial support.

Convert to named lambda parameters code action​

Thanks to KacperFKorban we have a new code action that converts a wildcard lambda into a lambda with parameters. This was only implemented for Scala 3 and will work from versions 3.7.2 and LTS 3.3.7.

Support using directives in worksheets​

Since Metals has been supporting Scala-CLI for a while, and it is Metals's recommended tool for scripts, we are further embracing Scala-CLI style, and using directives are now supported also in the worksheets. Thanks go to tgodzik for adding this improvement.

Improve auto-fill arguments​

For a while now, Metals had a special completion for auto-filling argument names, however it was somewhat hidden. Now, the discoveribility of that feature was improved, and it naturally appear in the completion suggestion list. Thanks, LiathHelvetica and natsukagami, for making the change.

Discover tests for ZIO test framework​

With this release also comes support for discovering and running single test cases from Metals when using the ZIO test framework. Thanks go to kaplan-shaked, making this their first contribution!

Miscellaneous​

  • improvement : Able to get environment variables from shell ajafri2001
  • improvement: prefer .bazelproject as the Bazel BSP root harpocrates
  • improvement: add additional ScalaTest WordSpec types tmilner
  • fix: add backticks in hover output when needed harpocrates
  • fix: show more precise signature help types harpocrates
  • fix: consider build.mill and build.mill.scala when calculating Mill digest sake92
  • fix: completions respect backticks at defn site harpocrates
  • fix: don't rename if old and new packages are the same for package object kasiaMarek
  • fix: add fallback presentation compiler for Java kasiaMarek
  • fix: Add type param inlay hint for constuctor calls kasiaMarek
  • improvement: add selection ranges for name harpocrates
  • improvement: add folding range for function call harpocrates
  • feat: respect LSP build target no-ide tag ysedira
  • improvement: queue or cancel previous connect request kasiaMarek
  • fix & improvement: improvements in selection ranges harpocrates
  • feat: convert string to interpolation on ${ harpocrates
  • fix: don't remove non-existent entries from classpath kasiaMarek

Contributors​

Big thanks to everybody who contributed to this release or reported an issue!

$ git shortlog -sn --no-merges v1.5.2..v1.5.3
  19	Tomasz Godzik
  16	amit.miran
  14	Scalameta Bot
  13	Alec Theriault
  11	scalameta-bot
   8	ajafri2001
   6	Brice Jaglin
   6	dependabot[bot]
   6	kasiaMarek
   5	Kacper Korban
   5	Katarzyna Marek
   5	Tobias Roeser
   5	scarf
   3	Przemyslaw Wierzbicki
   3	Sakib Hadziavdic
   2	Myungbae Son
   1	Amit Miran
   1	Christopher Vogt
   1	Jens Kouros
   1	Maciej Dragun
   1	Michal Pawlik
   1	Shaked Kaplan
   1	Tom Milner
   1	ysedira

Merged PRs​

v1.5.3 (2025-05-13)​

Full Changelog

Merged pull requests:

]]> <![CDATA[Metals v1.5.2 - Strontium]]> http://scalameta.org/metals/blog/2025/03/26/strontium http://scalameta.org/metals/blog/2025/03/26/strontium Wed, 26 Mar 2025 00:00:00 GMT We're happy to announce the release of Metals v1.5.2, which continues to improve overall user experience and stability of Metals. This release includes a number of new features, bug fixes and improvements. Especially worth mentioning is the fix for the Scala 2 issue, which previously caused most interactive features to break when using a type defined in a package object.

Commits since last release145
Merged PRs132
Contributors16
Closed issues42
New features5

For full details: https://github.com/scalameta/metals/milestone/77?closed=1

Metals is a language server for Scala that works with VS Code, Vim, Emacs, Zed, Helix and Sublime Text. Metals is developed at the Scala Center and VirtusLab with the help from contributors from the community.

TL;DR​

Check out https://scalameta.org/metals/, and give Metals a try!

Deduplicate compile requests​

In previous versions of Metals, we would sometimes send multiple compile requests for the same file expecting most of them to be fast. This worked reliably well in Bloop, but not so much in a lot of other build servers such as sbt.

Thanks to kasiaMarek we will try not to send multiple requests if we know a file hasn't changed between them. This should help in a number of cases and make the experience more reliable.

Add exact location for the test failure​

Previously, when running tests in Metals with VS Code Test Explorer, the location of the test failure was not shown, only the start of the test case. Now, we will correctly show the exact location of the test failure, which should make it easier to navigate to the failing test.

test-loc

Convert sbt style deps on paste in for scala-cli​

Thanks to majk-p any sbt style dependencies that you paste into a Scala CLI file after //> using dep will be automatically converted to Scala CLI style dependencies. This was previously only supported in a code action, but turns out to be useful enough to apply the rewrite automatically on paste.

paste-dep

Add test cases discovery for TestNG​

Thanks to kasiaMarek it's now possible to run TestNG tests inside Metals, which was previously not possible.

This would mean following test cases will now show lenses or test explorer icon next to them:

import org.testng.annotations.Test

class TestNG {
    @Test
    def testOK(): Unit = {
        assert(true)
    }
}

Improvements to automatic imports​

Whenever importing a particular symbol, Metals would previously suggest all the possible symbol with the expected name. However, in a lot of cases, those symbol might already have a method being invoked on them, which means that only symbols containing that method should be suggested.

For example in the following code:

object O{
  Future.successful(1)
}

we don't need to suggest java.concurrent.Future, but only scala.concurrent.Future since only the latter contains the successful method. If none of the symbols contains that specific method, we will revert to showing all symbols. Let us know if this is a helpful behaviour or if you see additional cases where this could be improved.

Remove Ammonite script support​

Some time ago we have asked in discussions in our Github repository about the possibility of removing support for Ammonite scripts. We have not received any overwhelming feedback to keep it, so we have decided to remove it. If you have any concerns or questions about this change, please let us know.

The removal was directly prompted by the fact that there were serious issues with Ammonite support with no users reporting them or anyone from maintainers being aware of them. Which points to the fact that the feature is not widely used.

This will also help to to ease the maintenance burden and to focus more on stability of Metals. Scala Scripts still are and will be supported via Scala CLI, so for anyone using Ammonite we suggest switching to Scala CLI. Scala CLI is the default Scala runner for Scala 3 and we believe it offers overall better experience. If you see any useful Ammonite feature missing from Scala CLI don't hesitate to start a discussion in the Scala CLI repository.

Miscellaneous​

  • bugfix: Also infer type with complex expressions before method invocation tgodzik
  • bugfix: fix typeDefinition on backticked identifier harpocrates
  • bugfix: Fix when types are coming from package objects tgodzik
  • bugfix: Infer arg type properly when method uses complex parameters tgodzik
  • improvement: convert workspace folder to be a Metals project on chosen commands kasiaMarek
  • Fix extracting values for fewer braces majk-p
  • bugfix: Regenerate mill BSP config on incorrect version kasiaMarek
  • bugfix: Add missing completion in args in generic method with default args harpocrates
  • improvement: Add file location also to stacktrace printed to stdout kasiaMarek
  • bugfix: Don't propose inaccessible named arg defaults harpocrates
  • feature: Support completions inside of backticks harpocrates
  • bugfix: Support show decompiled and show tasty for Bazel kasiaMarek
  • bugfix: Fix invalid config message when multiple scalafmt files are used with 'include' Sporarum
  • bugfix: don't propose inaccessible named arg defaults harpocrates
  • bugfix: don't prefix scope completions from supertype harpocrates
  • Add function params selection range blaz-kranjc
  • bugfix: Don't fail when deleting temporary files tgodzik
  • bugfix: Treat self types as parent types in go to implementation context KacperFKorban zainab-ali kasiaMarek
  • fix: look for implementations in rename for possibly overridden type aliases kasiaMarek
  • improvement: Ask to start http server if not running (tgodzik)
  • improve error messages when no main classes can be found cvogt
  • fix: go to def should lead to all apply, object and class (Scala 2) kasiaMarek
  • improvement: Add jar search command to metals view tgodzik
  • fix: generate auto-imports for more pattern completions (harpocrates)
  • fix: colliding pattern and scope completions #7295 (harpocrates)
  • improvement: add CompileTarget server command cvogt
  • bugfix: Try and improve credentials handling when downloading dependencies tgodzik
  • Suggest open diagnostics for debug compile errors cvogt
  • feat: convert sbt style deps on paste in for scala-cli test.dep scarf005
  • bugfix: Fix issues when we would rename more symbols than needed tgodzik
  • bugfix: Make sure to choose the best import option in unambiguous cases tgodzik
  • improvement: Add scalafix and Scala 3 Presentation Compiler to DownloadDependencies tgodzik

Contributors​

Big thanks to everybody who contributed to this release or reported an issue!

$ git shortlog -sn --no-merges v1.5.1..v1.5.2
    38	Tomasz Godzik
    24	Scalameta Bot
    16	scalameta-bot
    10	kasiaMarek
     7	dependabot[bot]
     6	Alec Theriault
     5	Blaz Kranjc
     4	tgodzik
     3	Christopher Vogt
     3	Katarzyna Marek
     2	Chris Birchall
     1	Francesco Nero
     1	Kacper Korban
     1	Lorenzo Gabriele
     1	Quentin Bernet
     1	Seth Tisue
     1	scarf

Merged PRs​

v1.5.2 (2025-03-18)​

Full Changelog

Merged pull requests:

]]> <![CDATA[Metals v1.5.1 - Strontium]]> http://scalameta.org/metals/blog/2025/01/24/strontium http://scalameta.org/metals/blog/2025/01/24/strontium Fri, 24 Jan 2025 00:00:00 GMT We're happy to announce the release of Metals v1.5.1, which brings a hotfix for go to definition error reporting.

Commits since last release12
Merged PRs9
Contributors6
Closed issues4
New features0

For full details: https://github.com/scalameta/metals/milestone/76?closed=1

Metals is a language server for Scala that works with VS Code, Vim, Emacs, Zed, Helix and Sublime Text. Metals is developed at the Scala Center and VirtusLab with the help from contributors from the community.

TL;DR​

Check out https://scalameta.org/metals/, and give Metals a try!

Create an error report only on an empty definition​

Fix for a bug, where an error report would be created always on go to definition action.

Miscellaneous​

  • improvement: Don't fail on creating short type (Scala 2) kasiaMarek
  • improvement: Default to empty object if no metals section tgodzik
  • improvement: Use only current source tree for searching for local symbols in pc (Scala 3) kasiaMarek

Contributors​

Big thanks to everybody who contributed to this release or reported an issue!

$ git shortlog -sn --no-merges v1.5.0..v1.5.1
     5	kasiaMarek
     2	Scalameta Bot
     3	Tomasz Godzik
     1	Katarzyna Marek
     1	dependabot[bot]
     1	tgodzik

Merged PRs​

v1.5.1 (2025-01-24)​

Full Changelog

Merged pull requests:

]]> <![CDATA[Metals v1.5.0 - Strontium]]> http://scalameta.org/metals/blog/2025/01/22/strontium http://scalameta.org/metals/blog/2025/01/22/strontium Wed, 22 Jan 2025 00:00:00 GMT We're happy to announce the release of Metals v1.5.0, which brings an array of bugfixes and improvements as we keep working on Metals stability.

Commits since last release85
Merged PRs61
Contributors11
Closed issues18
New features2

For full details: https://github.com/scalameta/metals/milestone/75?closed=1

Metals is a language server for Scala that works with VS Code, Vim, Emacs, Zed, Helix and Sublime Text. Metals is developed at the Scala Center and VirtusLab with the help from contributors from the community.

TL;DR​

Support for 2.13.16​

With the new release comes support for Scala 2.13.16. You can read release highlighs in [the Scala 2.13.16 release notes] the Scala 2.13.16 release notes.

Fix for Metals stopped compiling bug​

Previous versions of Metals could sometimes stop compiling the code and fail to report any new errors. This bug was related to a feature, where Metals would pause compilation when focusing out of editor Window. The feature was removed completely, since there was little benefit from it and it was tricky to make it work. If you experienced this bug or a similar one, let us know if this release fixes in for you. Thanks go to tgodzik for debugging this issue.

Error reports improvements​

In one of the previous versions of Metals we added mechanisms to save error reports under .metals/.reports. In case an error was more prominent it could create a large number of duplicate reports.

Now, the reports will be deduplicated properly and the information about created ones will be logged to improve their visibility. As previously, full list of generated reports is visible in the Metals doctor and the .metals/.reports directory.

Inlay hints for worksheets​

Starting from this release, worksheet decorations will be displayed using inlay hints instead of the previous custom solution. This will make worksheet support available for editors that don't implement this extension (e.g. Zed). Thanks tgodzik for implementing this transition.

Miscellaneous​

  • bugfix: correctly set excludedPackages on startup harpocrates
  • bugfix: don't show incorrect docs for inner methods kasiaMarek
  • bugfix: add support for -native suffix in .mill-version lolgab
  • improvement: add $ as a trigger character for completions harpocrates
  • bugfix: completion of args in method w/ default args harpocrates
  • bugfix: syntax for worksheet imports btrachey
  • bugfix: workaround for hover for multi declaraction in Scala 3 kasiaMarek
  • bugfix: make inlay hint resolve not dependant on didFocus, which is a part of Metals custom protocol and not supported by all editors kasiaMarek
  • improvement: make folding regions more consistent and allow for custom setting of folding threshold kasiaMarek
  • improvement: handle incorrect scalafmtConfigPath gracefully Austinito
  • improvement: if no mode chosen by the client, use log for bsp status by default tgodzik
  • bugfix: skip using directives for auto import position when missing newline kasiaMarek
  • improvement: use presentation compiler as first strategy for go to definition kasiaMarek
  • feature: infer base package for package ralated functionalities harpocrates
  • feature: add switch build server button to Build Commands section tgodzik
  • improvement: suggest bsp switch if bloopInstall fails kasiaMarek

Contributors​

Big thanks to everybody who contributed to this release or reported an issue!

$ git shortlog -sn --no-merges v1.4.2..v1.5.0
    31	Tomasz Godzik
    26	Scalameta Bot
    16	kasiaMarek
     4	Alec Theriault
     2	Austinito
     1	Adrien Piquerez
     1	Anton Sviridov
     1	Brian Tracey
     1	Lorenzo Gabriele
     1	Timothy John Perisho Eccleston
     1	dependabot[bot]

Merged PRs​

v1.5.0 (2025-01-22)​

Full Changelog

Merged pull requests:

]]> <![CDATA[Metals v1.4.2 - Palladium]]> http://scalameta.org/metals/blog/2024/12/16/palladium http://scalameta.org/metals/blog/2024/12/16/palladium Mon, 16 Dec 2024 00:00:00 GMT We're happy to announce the release of Metals v1.4.2, which yet again focuses on stability, but thanks to our contributors we also have a new code action.

Commits since last release93
Merged PRs71
Contributors13
Closed issues17
New features1

For full details: https://github.com/scalameta/metals/milestone/74?closed=1

Metals is a language server for Scala that works with VS Code, Vim, Emacs, Zed, Helix and Sublime Text. Metals is developed at the Scala Center and VirtusLab with the help from contributors from the community.

TL;DR​

Check out https://scalameta.org/metals/, and give Metals a try!

Infer method code action​

Thanks to great work by ag91 it's now possible to ask Metals to infer a method definition based on it's usage when symbol was not found.

This works similar to the "Create new symbol" code action which would create a new Scala file with the added symbol. Now, for anything starting with a lower case we offer to create a method instead.

This will work both when the symbol is used as a parameter:

first-example

as well as a standalone function call:

second-example

The feature has only been implemented for Scala 2 for the time being and there might be still some unsupported cases.

Contributors​

Big thanks to everybody who contributed to this release or reported an issue!

$ git shortlog -sn --no-merges v1.4.1..v1.4.2
    30	Tomasz Godzik
    29	Scalameta Bot
    10	Andrea
     7	dependabot[bot]
     3	Francesco Nero
     3	kasiaMarek
     3	scarf
     2	Jean-Luc Deprez
     2	Katarzyna Marek
     1	Ruby Iris Juric
     1	nocontribute
     1	rochala

Miscellaneous

  • bugfix: Check if inlay hints refresh is enabled tgodzik
  • bugfix: Show implicit chained calls in inlay hints francesconero
  • bugfix: Don't set empty edits - fixes code actions for Zed tgodzik
  • bugfix: Respect customProjectRoot in BspConnector spangaer
  • improvement: Change default StatusBarState to LogMessage tgodzik
  • bugfix: Fix issue when anonymous function name would be added as prefix tgodzik
  • bugfix: Presentation Compiler is now loaded with correct classloader rochala
  • improvement: if no binary version in jar path try using build target info kasiaMarek
  • fix: don't look for overshadow conflicts for symbols not in the scope kasiaMarek
  • improvement: Make including detail in completion label configurable Sorixelle
  • fix: use alternative definition with stripped synthetic filename$package. kasiaMarek
  • improvement: by default support scala-cli power options kasiaMarek
  • bugfix: Update Bloop to 2.0.6 to fix importing build when using pipeling in sbt tgodzik

Merged PRs​

v1.4.2 (2024-12-13)​

Full Changelog

Merged pull requests:

]]> <![CDATA[Metals v1.4.1 - Palladium]]> http://scalameta.org/metals/blog/2024/11/15/palladium http://scalameta.org/metals/blog/2024/11/15/palladium Fri, 15 Nov 2024 00:00:00 GMT We're happy to announce the release of Metals v1.4.1, which focuses mostly on smaller fixes to the latest 1.4.0 release together with updating Bloop to the latest version, which includes it's own improvements and fixes.

Commits since last release37
Merged PRs36
Contributors4
Closed issues7
New features0

For full details: https://github.com/scalameta/metals/milestone/73?closed=1

Metals is a language server for Scala that works with VS Code, Vim, Emacs, Zed, Helix and Sublime Text. Metals is developed at the Scala Center and VirtusLab with the help from contributors from the community.

TL;DR​

Check out https://scalameta.org/metals/, and give Metals a try!

Bloop Update​

Newest Bloop brings two main improvements for Metals users:

  • Wart Remover should now work correctly, users will need to reimport the build.
  • Best effort compilation issues should now be fixed and users are encouraged to tests it out by starting Metals with -Dmetals.enable-best-effort=true or by putting that property into metals.serverProperties in case of VS Code.

You can read about a specific changes in the release notes

Miscellaneous​

  • bugfix: Fix extract function not showing up tgodzik
  • bugfix: Properly escape jar: paths on Windows tgodzik
  • bugfix: Run by default also synthetic mains such as scripts tgodzik
  • bugfix: Correctly check if a given config exists in scalafix.conf tgodzik
  • improvement: Always find all references including companion objects and classes. tgodzik
  • bugfix: Fix pasting into multiline strings when indent would be wrong. tgodzik
  • improvement: Don't automatically add release flag for versions from 17 tgodzik

Contributors​

Big thanks to everybody who contributed to this release or reported an issue!

$ git shortlog -sn --no-merges v1.4.0..v1.4.1
    16	Tomasz Godzik
    12	Scalameta Bot
     5	dependabot[bot]
     1	nguyenyou

Merged PRs​

v1.4.1 (2024-11-14)​

Full Changelog

Merged pull requests:

]]> <![CDATA[Metals v1.4.0 - Palladium]]> http://scalameta.org/metals/blog/2024/10/24/palladium http://scalameta.org/metals/blog/2024/10/24/palladium Thu, 24 Oct 2024 00:00:00 GMT We're happy to announce the release of Metals v1.4.0, with the main focus on introducing Bloop 2.0.0. Of course, this release also includes many improvements.

Commits since last release205
Merged PRs142
Contributors17
Closed issues54
New features2

For full details: https://github.com/scalameta/metals/milestone/72?closed=1

Metals is a language server for Scala that works with VS Code, Vim, Emacs, Zed, Helix and Sublime Text. Metals is developed at the Scala Center and VirtusLab with the help from contributors from the community.

TL;DR​

Check out https://scalameta.org/metals/, and give Metals a try!

Bloop 2​

Bloop is the default build server used by both Metals and Scala CLI, with the latter also serving as the default Scala command since Scala 3.5.0. However, for quite some time, Scala CLI was using a separate fork of Bloop, which occasionally led to users running two build servers simultaneously. This was far from ideal in terms of memory consumption. With Bloop 2.0.0, we have discontinued the fork, effectively resolving this issue.

This change also means that all the improvements made by Alexandre Archambault in the separate Bloop fork are now integrated into the main version. One of the most significant enhancements was the switch to Unix domain sockets, which should improve the reliability and speed of connections to the build server.

The above change has however made it necessary for us to adopt JDK 17 as the primary JDK for running Bloop and Metals. You should still be able to compile your code for earlier JDK versions without any issues; this will be handled by metals when you adjust the metals.javaHome setting to the desired Java version. That version is used to run the build tools and build servers, which then will be aware of it In case of Bloop it means that if no -release flag or similar is added, Bloop will add it automatically to make sure the code is compiled correctly on a given JDK version. Similarly, Metals will add that flag to get all the interactive features from the compiler.

The Java version used by Metals itself is managed separately and will be automatically detected or downloaded as needed.

Metals will also attempt to shut down the old Bloop server and you might see a notification about it. It should be perfectly safe to approve that action as the old server will no longer be used by any tool known to us.

Metals allows users to customize the default options for the Bloop build server. However, in most cases, it is best to use the defaults, which will be applied if the metals.bloopJvmOptionssetting is missing or set to an empty array.

The new default JVM options for Bloop are as follows:

"metals.bloopJvmOptions" : [
      "-Xss4m",
      "-XX:MaxInlineLevel=20", // Specific option for faster C2, ignored by GraalVM
      "-XX:+UseZGC", // ZGC returns unused memory back to the OS, so Bloop does not occupy so much memory if unused
      "-XX:ZUncommitDelay=30",
      "-XX:ZCollectionInterval=5",
      "-XX:+IgnoreUnrecognizedVMOptions", // Do not fail if an non-standard (-X, -XX) VM option is not recognized.
      "-Dbloop.ignore-sig-int=true"
]

If you are having any issues with the build server it might be worth experimenting with those defaults.

We also adjusted Metals default options similarly in VS Code to further minimize the amount of memory used overall.

Detect custom mains​

Previously, we would only discover main classes defined in standard ways such as when:

  • using @main annotation for Scala3
  • extending App
  • explicit def main(args: Array[String]): Unit method
  • scripts

However, users might actually want to create more ways of defining them such as through compiler plugins. Turns out this is the same case we previously had with scripts. In this release, we extended that mechanism and any unknown main classes will be show with code lenses at the top of the file the same way as with scripts.

Miscellaneous​

  • bugfix: disambiguate workspace completions for vals in Scala 3 kasiaMarek
  • bugfix: correctly handle odd formatting while indexing source jars kasiaMarek
  • improvement: Only compile current target when debugging or using scalafix tgodzik
  • fix: delete test suites for deleted build targets kasiaMarek
  • improvement: clear diagnostics in downstream targets kasiaMarek
  • improvement: Improve heuritics used for fallback symbol search tgodzik
  • bugfix: use semanticdb also for local symbols and when references not supported in PC kasiaMarek
  • bugfix: Add backticks for inferred type when needed tgodzik
  • bugfix: Use default bloop properties if provided empty array tgodzik
  • bugfix: Catch possible syntax errors tgodzik
  • bugfix: Make sure best effort works with verbose tgodzik
  • improvement: Don't allow empty sbtScript setting tgodzik
  • Disable OrganizeImports commands if they are not available wjoel
  • improvement: add coursier repositories instead of overwrite kasiaMarek
  • bugfix: completions for using directive deps in test scope kasiaMarek
  • feature: Add "opaque type" keyword completions tgodzik
  • bugfix: index top level with inner when apply with { } in method kasiaMarek
  • bugfix: Allow -release flag for Scala 3 to get proper completions tgodzik
  • fix: Get correct classpath for running debug using Mill BSP kasiaMarek
  • improvement: Include jvm opts and environment variables when running tests #6753 (masonedmison)
  • bugfix: Check if locally available sbt is actually a file and not a directory tgodzik
  • improvement: Fallback to last successful semantic tokens instead of throwing to avoid VS Code reproting server as unresponsive tgodzik
  • bugfix: Finer grained accessibility check for auto-imports that includes the private with qualifier masonedmison
  • chore: Freeze bloop plugin for versions of sbt lower than 1.5.8 tgodzik
  • bugfix: Make sure Bloop is always properly restarted tgodzik
  • bugfix: Exclude comma if included in symbol range for references tgodzik
  • bugfix: Stop Metals from saving shared JVM indexes with XDG path violation untainsYD
  • chore: Update scalafix to 0.13.0 to include Scala 3 inferred type bjaglin
  • bugfix: Don't hang when checking for cache folders on Windows tgodzik
  • improvement: Limit number of semanticdb files read at the same time to limit possibility of OOM tgodzik
  • improvement: Basic support for new .mill and .mill.scala source files lolgab
  • bugfix: Fix Metals hanging on Windows tgodzik

Contributors​

Big thanks to everybody who contributed to this release or reported an issue!

$ git shortlog -sn --no-merges v1.3.5..v1.4.0
    82	Tomasz Godzik
    52	Scalameta Bot
    13	Lorenzo Gabriele
    13	kasiaMarek
    10	dependabot[bot]
     8	tgodzik
     6	Mason Edmison
     3	Alexandre Archambault
     3	Anup Chenthamarakshan
     3	Katarzyna Marek
     2	Joel Wilsson
     2	Kacper Korban
     2	Yarosλaβ .
     2	nocontribute
     2	scarf
     1	Brice Jaglin
     1	Seth Tisue

Merged PRs​

v1.4.0 (2024-10-23)​

Full Changelog

Merged pull requests:

]]> <![CDATA[Metals v1.3.5 - Thallium]]> http://scalameta.org/metals/blog/2024/08/01/thallium http://scalameta.org/metals/blog/2024/08/01/thallium Thu, 01 Aug 2024 00:00:00 GMT Metals v1.3.5 is a bugfix release and it's main purpose is to disable best effort compilation for the time being.

This version also removed support for some of Scala 2.12 and 2.13 versions. We will keep releasing Metals for the last 4 versions in the 2.12.x and 2.13.x lines. This means that older versions will not keep getting bugfixes or new features, which are version specific, but Metals will keep working for them.

Commits since last release24
Merged PRs14
Contributors4
Closed issues3
New features0

For full details: https://github.com/scalameta/metals/milestone/71?closed=1

Metals is a language server for Scala that works with VS Code, Vim, Emacs, Zed, Helix and Sublime Text. Metals is developed at the Scala Center and VirtusLab with the help from contributors from the community.

TL;DR​

Check out https://scalameta.org/metals/, and give Metals a try!

Disable best effort compilation​

Some users when testing the newest RC of Scala 3.5.0, which supports best effort compilation, reported that Metals show some errors in the code, which is not the case for Scala 3.4.x or when using sbt.

This will be most likely fixed later on, but for now, we decided to disable best effort by default. If you want to still test it out you need to start Metals with -Dmetals.enable-best-effort=true or put that into metals.serverProperties in case of VS Code.

Contributors​

Big thanks to everybody who contributed to this release or reported an issue!

$ git shortlog -sn --no-merges v1.3.4..v1.3.5
     14	Tomasz Godzik
     7	Scalameta Bot
     2	Katarzyna Marek
     1	tgodzik

Miscellaneous​

  • fix: don't suggest completions for param names in definition kasiaMarek

Merged PRs​

v1.3.5 (2024-08-01)​

Full Changelog

Merged pull requests:

]]> <![CDATA[Metals v1.3.4 - Thallium]]> http://scalameta.org/metals/blog/2024/07/24/thallium http://scalameta.org/metals/blog/2024/07/24/thallium Wed, 24 Jul 2024 00:00:00 GMT We're happy to announce the release of Metals v1.3.4, which above all improves the experience of working with non-compiling Scala 3 projects.

Commits since last release31
Merged PRs21
Contributors6
Closed issues12
New features2

For full details: https://github.com/scalameta/metals/milestone/70?closed=1

Metals is a language server for Scala that works with VS Code, Vim, Emacs, Zed, Helix and Sublime Text. Metals is developed at the Scala Center and VirtusLab with the help from contributors from the community.

TL;DR​

Check out https://scalameta.org/metals/, and give Metals a try!

Scala 3 best effort compilation​

Starting with this release Metals will take advantage of Scala 3 best effort compilation. This should greatly improve the IDE experience of working with non-compiling code. With best effort compilation Scala 3 compiler will produce a tasty-like format files that can also include partially broken trees even when a module does not compile. Those files, similarly to normal tasty files, will be later consumed by the presentation compiler providing most up to date information about the project. This great feature has been delivered by jchyb and will be available starting with Scala 3.5.0.

Sort workspace members with the same name by frequency​

Workspace member completions with the same name are now sorted by their usage frequency, so the symbols more often referenced in project appear higher on the list of completions. This cool feature was added by Temurlock.

sort-by-freq

Miscellaneous

  • fix: show zero extent references for implicits when using pc
  • fix: correctly handle .scala files with shebang
  • fix: suggest import for maven/gradle when defaultBspToBuildTool = true
  • fix: only detect 100% sure test names tgodzik
  • fix: correctly prefix scope completions when conflicting for Scala 2

Contributors​

Big thanks to everybody who contributed to this release or reported an issue!

$ git shortlog -sn --no-merges v1.3.3..v1.3.4
     11	Simon Parten
     7	Katarzyna Marek
     7	Tomasz Godzik
     4	Scalameta Bot
     1	Jan Chyb
     1	temurlock

Merged PRs​

v1.3.4 (2024-07-24)​

Full Changelog

Merged pull requests:

]]> <![CDATA[Metals v1.3.3 - Thallium]]> http://scalameta.org/metals/blog/2024/07/12/thallium http://scalameta.org/metals/blog/2024/07/12/thallium Fri, 12 Jul 2024 00:00:00 GMT We're happy to announce the release of Metals v1.3.3, which brings a number of long awaited bugfixes and some new features.

Commits since last release41
Merged PRs37
Contributors3
Closed issues15
New features3

For full details: https://github.com/scalameta/metals/milestone/69?closed=1

Metals is a language server for Scala that works with VS Code, Vim, Emacs, Zed, Helix and Sublime Text. Metals is developed at the Scala Center and VirtusLab with the help from contributors from the community.

TL;DR​

Check out https://scalameta.org/metals/, and give Metals a try!

Index implementations in JDK sources​

Since Metals v1.3.0 it's possible to search for implementations of classes or classes' members inside the dependency sources. However, this wasn't enabled for JDK sources as it added a substantial amount of indexing time even in smaller projects.

In this version of Metals we added a central database that can be found under the .metals directory in user home, which contains shared indexes of JDK sources thus avoiding a need to index them more than once on any given machine.

jdk-sources

This great improvement was added by kasiaMarek

Value completions for union types​

Union types are a new feature in Scala 3 that allows types to be combined when we need to specify that certain value can be of more than one type.

For example we can have:

val a: Int | String = "Hello!"
val b: Int | String = 123

In this version of Metals kasiaMarek added support for value completions where union types are unions of specific literal types. If used together with intersection types it will still work as expected.

example

The feature will work on latest LTS and Next Scala versions as it required some work upstream in the compiler itself.

Allow debugging for all build servers​

For a long while it was possible to debug your code only when using Metals with Bloop or sbt server. This was caused by the fact that debugging was implemented in a separate library and would require additional data from the build tools.

In this version we were able to work around that and bring debugging capabilities to Metals in case a server doesn't provide debugging by itself. Unfortunately, in those cases hot code reload will not be available.

This should work both for main classes and tests.

Since this is quite a new feature please do let us know about any issues.

This is another great feature was brought by kasiaMarek.

Miscellaneous​

  • bugfix: correctly resolve project's java in doctor and problem resolver kasiaMarek
  • bugfix: Don't use -X options in .jvmopts for tests tgodzik
  • bugfix: auto import for really long names kasiaMarek
  • bugfix: Queue references calls to prevent OOM kasiaMarek
  • bugfix: MAke convert to named args for extends kasiaMarek
  • bugfix: Show errors for Scala 3 in Bazel correctly tgodzik
  • bugfix: change project ref setting to support VSCode workspace folder reload kasiaMarek
  • bugfix: use already imported package aliases for auto import kasiaMarek
  • bugfix: clear diagnostics after close for single file kasiaMarek

Contributors​

Big thanks to everybody who contributed to this release or reported an issue!

$ git shortlog -sn --no-merges v1.3.2..v1.3.3
    16	Katarzyna Marek
    16	Tomasz Godzik
     7	Scalameta Bot

Merged PRs​

v1.3.3 (2024-07-12)​

Full Changelog

Merged pull requests:

]]> <![CDATA[Metals v1.3.2 - Thallium]]> http://scalameta.org/metals/blog/2024/06/19/thallium http://scalameta.org/metals/blog/2024/06/19/thallium Wed, 19 Jun 2024 00:00:00 GMT We're excited to announce the release of Metals v1.3.2. This new version not only addresses numerous bugs but also enhances the experience of working with code that does not compile.

Commits since last release87
Merged PRs82
Contributors13
Closed issues26
New features1

For full details: https://github.com/scalameta/metals/milestone/68?closed=1

Metals is a language server for Scala that works with VS Code, Vim, Emacs, Zed, Helix and Sublime Text. Metals is developed at the Scala Center and VirtusLab with the help from contributors from the community.

TL;DR​

Check out https://scalameta.org/metals/, and give Metals a try!

Outline compilation​

Metals relies on information produced during compilation for much of its functionality. This limits the usefulness of many Metals features when the code is broken either by providing outdated information or no information if the project was never successfully compiled.

Starting with this release Metals will utilize outline compilation to get current information about not compiling files for Scala 2.12.x and 2.13.x. This should improve the experience of working with not compiling code.

There are a few limitations to this improvement, the biggest being that the information from outline compilation will be only available within the same build target (module).

Further work is being done on a similar approach for Scala 3, which should be available in one of the upcoming releases.

broken-code Completions on not compiling code

Before this release Metals would always use information from SemanticDB to search for references. Since SemanticDB is produced during compilation it would fail to find references for code that didn't compile. Now if SemanticDB information is missing or outdated Metals will fallback to using presentation compiler for reference search for all the files this concerns.

uncompiled-go-to-ref Find references on non-compiling code

Allow to override debug server startup timeout​

Until this release there was a fixed timeout for debug server startup time set to one minute. This proved to be insufficient for some larger projects and can now be overridden using a server property, e.g. -Dmetals.debug-server-start-timeout=90 increases the timeout to 90 seconds.

This is meant more as a temporary workaround, we also plan to work on decreasing the startup times, as this heavily impacts the user experience.

Miscellaneous​

  • improvement: suggest scalafix config amend if OrganizeImports.targetDialect = Scala3 missing for Scala 3 kasiaMarek
  • improvement: Show actual Scala versions supported by Metals in docs and when running metals --versions tgodzik
  • fix: Fix infinite indexing for broken sources tgodzik
  • fix: target jar classpath resolution for mill-bsp kasiaMarek
  • fix: use OS specific spelling for Path/PATH mdelomba
  • fix: search for gradle wrapper at project root kasiaMarek
  • fix: don't start mtags with full classpath tgodzik
  • fix: indexing for filenames with ``` kasiaMarek
  • fix: infer correct build target for jars tgodzik
  • fix: fix millw script tgodzik
  • fix: insert missing members in correct place for case classes kasiaMarek
  • fix: highlighting and completions for multiline strings in worksheets in Scala 3 kasiaMarek
  • feat: set unused tag for unused diagnostics ghostbuster91
  • fix: account for additional parenthesis around args in convert to named args kasiaMarek
  • improvement: don't run additional compilation on find references kasiaMarek
  • fix: indexing when java files contain #include header kasiaMarek
  • fix: correctly auto import when there is a renamed symbol with the same name in scope kasiaMarek
  • fix: handle implicit params in extract method kasiaMarek
  • fix: don't show implicit conversion for implicit params kasiaMarek
  • fix: resolve correctly project refs for sbt kasiaMarek
  • improvement: make sure we always have correct projectview file for Bazel tgodzik
  • fix: convert block args to named args when in parenthesis kasiaMarek
  • fix: auto import for class names with long packages kasiaMarek
  • fix: don't create semanticdb next to user sources for single files kasiaMarek
  • fix: don't override JAVA_HOME if it already exists for Bazel to avoid unnecessary restarts
  • improvement: recreate classloader if scalafix classloading fails. tgodzik

Contributors​

Big thanks to everybody who contributed to this release or reported an issue!

$ git shortlog -sn --no-merges v1.3.1..v1.3.2
    26	Katarzyna Marek
    24	Scalameta Bot
    18	Tomasz Godzik
     7	tgodzik
     4	dependabot[bot]
     1	Bohdan Buz
     1	Brian Wignall
     1	Grigorii Chudnov
     1	Kasper Kondzielski
     1	Michael DeLomba
     1	scalameta-bot
     1	spamegg
     1	temurlock

Merged PRs​

v1.3.2 (2024-06-19)​

Full Changelog

Merged pull requests:

  • improvement: Recreate classloader if scalafix classloading fails #6516 (tgodzik)
  • bugfix: Don't override JAVA_HOME if it already exists #6504 (tgodzik)
  • fix: don't create semanticdb next to user sources for single files #6509 (kasiaMarek)
  • refactor: code duplication in SupportedScalaVersions #6511 (buzbohdan)
  • build(deps): Update scalafmt-core from 3.8.1 to 3.8.2 #6514 (scalameta-bot)
  • build(deps): Update scalameta, semanticdb-scalac, ... from 4.9.5 to 4.9.6 #6515 (scalameta-bot)
  • build(deps): Update xnio-nio from 3.8.15.Final to 3.8.16.Final #6513 (scalameta-bot)
  • build(deps): Update ammonite-util from 3.0.0-M2-8-ba4429a2 to 3.0.0-M2-11-713b6963 #6512 (scalameta-bot)
  • improvement: Don't show bazel navigation issue always #6510 (tgodzik)
  • fix: propagate jvmopts to tests #6505 (gchudnov)
  • fix: prefer latter fully qualified name parts when building trigrams for fuzzy search #6482 (kasiaMarek)
  • fix: convert block args to named args when in parenthesis #6487 (kasiaMarek)
  • Add missing word #6502 (bwignall)
  • chore: Don't recalculate build tools every time #6462 (tgodzik)
  • improvement: Make sure we always have correct projectview file #6457 (tgodzik)
  • improvement: sort abstract members for auto implement #6496 (kasiaMarek)
  • fix: resolve correctly project refs for sbt #6486 (kasiaMarek)
  • improvement: don't delete classpath jars for running main from .metals/.tmp before server shutdown #6495 (kasiaMarek)
  • improvement: allow to override debug server startup timeout #6492 (kasiaMarek)
  • fix: don't show implicit conversion for implicit params #6493 (kasiaMarek)
  • improvement: Run mtags check parallel and set maximum timeout #6451 (tgodzik)
  • build(deps): Update protobuf-java from 4.27.0 to 4.27.1 #6489 (scalameta-bot)
  • build(deps): Update scribe, scribe-file, scribe-slf4j2 from 3.14.0 to 3.15.0 #6490 (scalameta-bot)
  • fix: use server command for doctor run in status bar #6474 (kasiaMarek)
  • fix: handle implicit params in extract method #6479 (kasiaMarek)
  • fix: correctly auto import when there is a renamed symbol with the same name in scope #6480 (kasiaMarek)
  • fix: allow for #include header #6473 (kasiaMarek)
  • improvement: don't run compileAndLookForNewReferences #6429 (kasiaMarek)
  • chore: Unignore and fix references Bazel test #6458 (tgodzik)
  • feat: Set unused tag for unused diagnostics #6378 (ghostbuster91)
  • fix: Account for additional parenthesis around args in convert to named args #6455 (kasiaMarek)
  • improvement: batch pc references calls #6453 (kasiaMarek)
  • build(deps): Update scribe, scribe-file, scribe-slf4j2 from 3.13.5 to 3.14.0 #6471 (scalameta-bot)
  • build(deps): Update guava from 33.2.0-jre to 33.2.1-jre #6469 (scalameta-bot)
  • build(deps): Update ammonite-util from 3.0.0-M2-6-38698450 to 3.0.0-M2-8-ba4429a2 #6470 (scalameta-bot)
  • build(deps): bump @easyops-cn/docusaurus-search-local from 0.40.1 to 0.41.0 in /website #6467 (dependabot[bot])
  • build(deps): bump @docusaurus/plugin-client-redirects from 3.2.1 to 3.4.0 in /website #6466 (dependabot[bot])
  • build(deps): bump @docusaurus/core from 3.2.1 to 3.4.0 in /website #6465 (dependabot[bot])
  • build(deps): bump scalacenter/sbt-dependency-submission from 2 to 3 #6464 (dependabot[bot])
  • build(deps): Update requests from 0.8.2 to 0.8.3 #6463 (scalameta-bot)
  • Update faq.md #6461 (spamegg1)
  • bugfix: Filter out target #6460 (tgodzik)
  • fix: pc functions for multiline strings in worksheets in scala 3 #6456 (kasiaMarek)
  • fix: insert missing members in correct place for case classes #6454 (kasiaMarek)
  • refactor: Don't try to download artifacts in ProblemResolverSuite #6449 (tgodzik)
  • improvement: do not cache presentation compilers for find references #6448 (kasiaMarek)
  • fix: use pc for references when go to def on definition #6447 (kasiaMarek)
  • improvement: Retry rename tests, since they seem most flaky #6450 (tgodzik)
  • bugfix: Use actual method arguments from DAP server interface #6444 (tgodzik)
  • bugfix: Fix millw script #6446 (tgodzik)
  • build(deps): Update cli_3, scala-cli-bsp from 1.3.1 to 1.3.2 #6443 (scalameta-bot)
  • bugfix: Infer correct build target for jars #6437 (tgodzik)
  • build(deps): Update xnio-nio from 3.8.14.Final to 3.8.15.Final #6442 (scalameta-bot)
  • build(deps): Update org.eclipse.lsp4j, ... from 0.22.0 to 0.23.1 #6434 (scalameta-bot)
  • fix: getting top levels for filenames with ``` #6430 (kasiaMarek)
  • build(deps): Update ammonite-util from 3.0.0-M2-5-1c823fef to 3.0.0-M2-6-38698450 #6441 (scalameta-bot)
  • bugfix: Don't start mtags with full classpath #6439 (tgodzik)
  • chore: Bump Bazel BSP to a version with newest fixes #6438 (tgodzik)
  • build(deps): Update org.eclipse.lsp4j, ... from 0.20.1 to 0.22.0 #6126 (scalameta-bot)
  • build(deps): Update munit from 1.0.0-RC1 to 1.0.0 #6435 (scalameta-bot)
  • build(deps): Update ammonite-util from 3.0.0-M2-3-b5eb4787 to 3.0.0-M2-5-1c823fef #6433 (scalameta-bot)
  • build(deps): Update bloop-launcher-core from 1.5.17 to 1.5.18 #6431 (scalameta-bot)
  • build(deps): Update protobuf-java from 4.26.1 to 4.27.0 #6432 (scalameta-bot)
  • fix: look for gradle wrapper at project root #6428 (kasiaMarek)
  • improvement: use pc for finding references of local symbols and when semanticdb is missing #5940 (kasiaMarek)
  • Fixed issue where oldPath wasn't using OS specific spelling for Path/PATH #6427 (mdelomba)
  • chore: Bump Scala Debug Adapter to latest #6425 (tgodzik)
  • fix: targetJarClasspath for mill-bsp #6424 (kasiaMarek)
  • improvement: Automatically update bazel bsp #6410 (tgodzik)
  • bugfix: Fix infinite indexing #6420 (tgodzik)
  • build(deps): Update ammonite-util from 3.0.0-M2-2-741e5dbb to 3.0.0-M2-3-b5eb4787 #6421 (scalameta-bot)
  • Outline compiler #6114 (kasiaMarek)
  • refactor: Move parts specific for workspace folder from MetalsLspServer #6347 (kasiaMarek)
  • chore: Bump Bazel BSP and add tests about warnings #6407 (tgodzik)
  • improvement: Show actual Scala versions supported by Metals #6417 (tgodzik)
  • improvement: suggest scalafix config amend if `OrganizeImports.target… #6389 (kasiaMarek)
  • build(deps): Update ujson from 3.3.0 to 3.3.1 #6422 (scalameta-bot)
  • build(deps): Update scalameta from 4.9.3 to 4.9.5 #6423 (scalameta-bot)
  • refactor: Add -Xsource:3 flag to easy migration to Scala 3 #6411 (tgodzik)
  • build(deps): Update ammonite-util from 3.0.0-M1-24-26133e66 to 3.0.0-M2-2-741e5dbb #6413 (scalameta-bot)
  • remove unused bloomfilter #6399 (Temurlock)
  • docs: Add release notes for Metals 1.3.1 #6403 (tgodzik)
]]> <![CDATA[Metals v1.3.1 - Thallium]]> http://scalameta.org/metals/blog/2024/05/16/thallium http://scalameta.org/metals/blog/2024/05/16/thallium Thu, 16 May 2024 00:00:00 GMT We're happy to announce the release of Metals v1.3.1, which brings in a couple of useful improvements.

Commits since last release74
Merged PRs64
Contributors9
Closed issues27
New features3

For full details: https://github.com/scalameta/metals/milestone/67?closed=1

Metals is a language server for Scala that works with VS Code, Vim, Emacs, Zed, Helix and Sublime Text. Metals is developed at the Scala Center and VirtusLab with the help from contributors from the community.

TL;DR​

Check out https://scalameta.org/metals/, and give Metals a try!

Resolve classpath lazily in Bazel​

Metals uses Bazel BSP to interact with Bazel itself via the Build Server Protocol. Up until this release, we would eagerly resolve the classpath that is needed for some of the Metals features. However, this caused indexing times to be huge in large Bazel projects as it is expensive to calculate it. To avoid that we now only resolve classpath for targets users are currently working on.

Let us know if you notice any more bottlenecks we can fix!

Replace slowTask with LSP progress​

There are several Language Server Protocol extensions that are used in Metals to provide features that go outside the LSP standard. This also included Slow task extension, but since a couple of LSP releases there has been a proper progress endpoint available. This is now used in Metals.

This means that editors that did not implement the slow task extension will now properly show the progress of tasks running within Metals. For anything that did implement it, there might be some visual changes. In Visual Studio Code the progress will be contained at the bottom in the status bar, which can be clicked on to see all current progress messages. Since, it will also contain all the current compilation, we removed Ongoing compilations section from the Metals view. This is possible thanks to the great work done by kasiaMarek.

No workspace support​

Thanks to kasiaMarek it's now possible to start Metals for a single file without a workspace. Metals will automatically use Scala CLI for such single files to provide as much support as possible including standard LSP features, such as completions, hover and more.

Miscellaneous​

  • bugfix: remove stale config files before bloopInstall for gradle kasiaMarek
  • improvement: do not throw on failed java indexing kasiaMarek
  • bugfix: handle type T = Object.type in type hierarchy indexing kasiaMarek
  • fix: retry calculating build tool digest kasiaMarek
  • improvement: don't override bloop java home if version greater or equal kasiaMarek
  • bugfix: obey hover markup kind capability kasiaMarek
  • improvement: add worksheet timeout setting kasiaMarek
  • bugfix: don't show private apply as a completion kasiaMarek
  • fix: try pc symbol before symbol alternatives in go to definition kasiaMarek
  • fix: include inline when printing param names kasiaMarek
  • bugfix: Set Path instead of PATH on windows tgodzik
  • improvement: remove unused imports on Scala 3.4+ bjaglin
  • fix: show implicit param when it is an apply kasiaMarek
  • fix: dealias type members in hover kasiaMarek
  • improvement: don't start new metals service for project ref kasiaMarek
  • fix: import from build tools, that aren't build server providers when using automatic bsp setting kasiaMarek
  • fix: send end progress if future finished with an exception kasiaMarek

Contributors​

Big thanks to everybody who contributed to this release or reported an issue!

$ git shortlog -sn --no-merges v1.3.0..v1.3.1
    25	Scalameta Bot
    22	Tomasz Godzik
    21	Katarzyna Marek
     1	Brice Jaglin
     1	Martin Mauch
     1	Vadim Chelyshov
     1	dependabot[bot]
     1	scalameta-bot
     1	tgodzik

Merged PRs​

v1.3.1 (2024-05-14)​

Full Changelog

Merged pull requests:

]]>