LSPServer is a package that implements the Language Server Protocol for Wolfram Language and allows a Wolfram Language kernel to run as an LSP server.
LSPServer implements several LSP features:
- Code diagnostics
- Suggestions for fixes
- Formatting files and selections
- Semantic highlighting
- Expand / shrink selection
- Outline
- Color swatches
- Symbol references
- Documentation on hover
This repo is for users who are interested in adding LSP support for Wolfram Language to LSP clients.
There are official Wolfram LSP clients for Sublime Text and Visual Studio Code.
LSPServer depends on CodeParser paclet, CodeInspector paclet, and CodeFormatter paclet.
LSPServer and its dependencies are included in Mathematica 13.0 and above.
Install LSPServer paclet and dependencies from the public paclet server:
PacletInstall["CodeParser"]
PacletInstall["CodeInspector"]
PacletInstall["CodeFormatter"]
PacletInstall["LSPServer"]
Build and install the LSPServer paclet locally
99% of users will not need to worry about using LSPServer directly. LSPServer is used internally when an LSP client launches a Wolfram kernel as an LSP server. This all happens in the background.
But it can be useful to run LSPServer when developing a new LSP client.
Create a file named server.wl:
Needs["LSPServer`"]
StartServer[]
And run from the command-line:
brenton@brenton2maclap % WolframKernel -noprompt -run Get\[\"server.wl\"\]
14:03:48.605 $CommandLine: {WolframKernel, -noprompt, -run, Get["server.wl"]}
14:03:48.607
14:03:48.608 $commProcess: StdIO
14:03:48.608
14:03:48.608 $ProcessID: 54603
14:03:48.609
14:03:48.609 $ParentProcessID: 54582
14:03:48.609
14:03:48.609 Starting server... (If this is the last line you see, then StartServer[] may have been called in an unexpected way and the server is hanging.)
14:03:48.610
Notice the proper character escapes on the command-line.
The kernel process is blocked waiting on input to its stdin.
Properly formed LSP JSON-RPC can be sent to the kernel, and the kernel would send its response to stdout.
Make sure that the paclets can be found on your system:
Needs["LSPServer`"]
You may get LibraryFunction messages:
14:49:15.663 $CommandLine: {/Applications/Mathematica.app/Contents/MacOS/WolframKernel, -noinit, -noprompt, -nopaclet, -nostartuppaclets, -noicon, -run, Needs["LSPServer`"];LSPServer`StartServer["/Users/user/logs/"]}
14:49:15.664
14:49:15.664 $commProcess: StdIO
14:49:15.664
14:49:15.665 $ProcessID: 22400
14:49:15.665
14:49:15.666 $ParentProcessID: 22394
14:49:15.666
14:49:15.667 Directory[]: /private/var/folders/90/4fbnjdqx3f791xb65c02fm2m000bfy/T/Wolfram-LSPServer
14:49:15.667
14:49:15.668 Starting server... (If this is the last line you see, then StartServer[] may have been called in an unexpected way and the server is hanging.)
14:49:15.668
LibraryFunction::version: The version number 7 of the library is not consistent with the current or any previous WolframLibraryVersion.
LibraryFunction::initerr: A nonzero error code 7 was returned during the initialization of the library /Users/user/Library/Mathematica/Paclets/Repository/LSPServer-1.6/LibraryResources/MacOSX-x86-64/LSPServer.dylib.
LibraryFunction::libload: The function GetStartupError_LibraryLink was not loaded from the file /Users/user/Library/Mathematica/Paclets/Repository/LSPServer-1.6/LibraryResources/MacOSX-x86-64/LSPServer.dylib.
14:49:16.129
14:49:16.129 Initialization failed: Failure["LibraryFunctionLoad", <|"Result" -> $Failed|>]
14:49:16.484
14:49:16.485 Language Server kernel did not shutdown properly.
14:49:16.485
14:49:16.487 This is the command that was used:
14:49:16.488 {/Applications/Mathematica.app/Contents/MacOS/WolframKernel, -noinit, -noprompt, -nopaclet, -nostartuppaclets, -noicon, -run, Needs["LSPServer`"];LSPServer`StartServer["/Users/user/logs/"]}
14:49:16.488
14:49:16.489 To help diagnose the problem, run this in a notebook:
Needs["LSPServer`"]
LSPServer`RunServerDiagnostic[{"/Applications/Mathematica.app/Contents/MacOS/WolframKernel", "-noinit", "-noprompt", "-nopaclet", "-nostartuppaclets", "-noicon", "-run", "Needs[\"LSPServer`\"];LSPServer`StartServer[\"/Users/user/logs/\"]"}]
14:49:16.490
14:49:16.490 Fix any problems then restart and try again.
14:49:16.491
14:49:16.492 KERNEL IS EXITING HARD
14:49:16.492
This means that LSPServer was built with a newer version of Wolfram System than your system supports.
To fix this, build LSPServer from source with the version of Wolfram System that you will use.
Turn on debug logging from the kernel.
Give a string argument to StartServer[]. This is a directory that kernel logs will be written to.
Needs["LSPServer`"];LSPServer`StartServer["/path/to/log/directory/"]