start a LSP for KeY

[wadoon]

A language server protocol for KeY files.

Intended Change

Plan

• Implement feature 1
• Implement feature 2
• Code cleanup
• Document the changes

Type of pull request

• Bug fix (non-breaking change which fixes an issue)
• Refactoring (behaviour should not change or only minimally change)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• There are changes to the (Java) code
• There are changes to the taclet rule base
• There are changes to the deployment/CI infrastructure (gradle, github, ...)
• Other:

Ensuring quality

• I made sure that introduced/changed code is well documented (javadoc and inline comments).
• I made sure that new/changed end-user features are well documented (https://github.com/KeYProject/key-docs).
• I added new test case(s) for new functionality.
• I have tested the feature as follows: ...
• I have checked that runtime performance has not deteriorated.
• For new Gradle modules: I added the Gradle module to the test matrix in
  .github/workflows/tests.yml

Additional information and contact(s)

The contributions within this pull request are licensed under GPLv2 (only) for inclusion in KeY.

[github-code-quality]

Code Coverage Overview

Languages: Java

Java / code-coverage/jacoco

The overall line coverage in commit 3914162 in the weigl/lsp branch is 22%. The line coverage in commit deec8ce in the main branch is 15%.

Show a line coverage summary of the most impacted files.

File	main deec8ce	weigl/lsp 3914162	+/-
org/key_project...ns/LspAction.kt	0%	0%	0%
org/key_project...ons/StartKey.kt	0%	0%	0%
org/key_project...key/lsp/main.kt	0%	0%	0%
org/key_project...ctionVisitor.kt	0%	0%	0%
org/key_project...umentService.kt	0%	46%	+46%
org/key_project...spaceService.kt	0%	52%	+52%
org/key_project...nguageServer.kt	0%	67%	+67%
org/key_project...tHighlighter.kt	0%	90%	+90%
org/key_project...tHighlighter.kt	0%	92%	+92%
org/key_project...CatchSymbols.kt	0%	96%	+96%

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_{Updated August 24, 2026 19:25 UTC}