Metals crashes silently at startup on macos with sublime text 3

[devlaam]

Moving over from Eclipse (no support for 2.13) to metals on sublime. Being a newbie, installed according to requirements. Package Conctrol: List Packages shows

I am on sbt 1.4.6 (running) and have opened a scala source file. The LSP context menu only contains grey items. Build does not seem to work. Returns "No Build System" when i select "Tools|Build". The diagnostics panel stays empty, the log panel (btw the toggle server panel as stated in the manual is not listed) shows: LSP-metals: 2021.01.13 13:06:29 INFO shutting down Metals, nothing more. A restart makes no difference.

What am i missing?

[tgodzik]

I haven't used sublime myself, but did you already have a look at the docs https://scalameta.org/metals/docs/editors/sublime.html ?

[devlaam]

You need to manage your build outside of sublime via sbt or bloop

That's no problem, but it would be nice if i could drill down in the code (more intelligently than sublime can already do based on text analysis) and make use of the LSP context assist.

[ayoub-benali]

the LSP buttons are unavailable simply because Metals isn't started so there is is no LSP session yet.

Can you post the server logs via LSP toggle log panel ? It is not clear yet why metals is shutting down.

[devlaam]

Can you post the server logs via LSP toggle log panel ? It is not clear yet why metals is shutting down.

As stated above, the only entry in the logs panel is

LSP-metals: 2021.01.13 13:53:09 INFO  shutting down Metals

there is nothing more.

[ayoub-benali]

that is strange. Can you do tail -f .metals/metals.log on your project root before opening your project ?

[devlaam]

There is no such hidden file in the directory from where i started sublime. And, just to be sure, a system wide search with both

find . -type d -iname ".metals" 
find . -type f -iname "metals.log"

came back empty as well.

[ayoub-benali]

An other attempt: Can you please edit LSP settings via preferences: LSP settings in command palette and set

 {
  "log_stderr": true,
  "log_debug": true
}

Do you see more log entries after running LSP toggle log panel ?

[ayoub-benali]

FYI log_payloads is an LSP setting and not for LPS-metals. use preferences: LSP settings to set it

[rwols]

Maybe sublime is not looking in the working directory. Now, i am on macos so this is understandable, since GUI apps are usually started without one.

A server should not care about the working directory. But, it could care about the folders the editor has open. Try opening a folder instead of a single file.

[devlaam]

Opening a folder does not seem to make a difference in the setting working dir and it does not influence the outcome of the issue.

[rwols]

Opening a folder does not seem to make a difference in the setting working dir and it does not influence the outcome of the issue.

It does. You need to close the current window, then open a new window either via the top menubar with File > Open Folder, or via the command-line with subl path/to/folder.

[rwols]

You can verify what your window folders are by opening the console via View > Show Console and running

window.folders()

in that console.

[devlaam]

Yes, i think we can learn something now, an java.util.concurrent.CompletionException: java.lang.NullPointerException is thrown. (null in scala: yaks! 😮 ):

:: --> LSP-metals initialize(1): {'initializationOptions': {'inputBoxProvider': True}, 'processId': 56735, 'capabilities': {'textDocument': {'synchronization': {'dynamicRegistration': True, 'willSaveWaitUntil': True, 'didSave': True, 'willSave': True}, 'references': {'dynamicRegistration': True}, 'hover': {'dynamicRegistration': True, 'contentFormat': ['markdown', 'plaintext']}, 'formatting': {'dynamicRegistration': True}, 'signatureHelp': {'dynamicRegistration': True, 'signatureInformation': {'documentationFormat': ['markdown', 'plaintext'], 'parameterInformation': {'labelOffsetSupport': True}}}, 'codeAction': {'dynamicRegistration': True, 'codeActionLiteralSupport': {'codeActionKind': {'valueSet': []}}}, 'definition': {'dynamicRegistration': True, 'linkSupport': True}, 'publishDiagnostics': {'relatedInformation': True}, 'completion': {'dynamicRegistration': True, 'completionItemKind': {'valueSet': [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25]}, 'completionItem': {'snippetSupport': True}}, 'documentHighlight': {'dynamicRegistration': True}, 'typeDefinition': {'dynamicRegistration': True, 'linkSupport': True}, 'colorProvider': {'dynamicRegistration': True}, 'declaration': {'dynamicRegistration': True, 'linkSupport': True}, 'implementation': {'dynamicRegistration': True, 'linkSupport': True}, 'rangeFormatting': {'dynamicRegistration': True}, 'rename': {'dynamicRegistration': True}, 'documentSymbol': {'dynamicRegistration': True, 'symbolKind': {'valueSet': [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26]}, 'hierarchicalDocumentSymbolSupport': True}}, 'window': {'workDoneProgress': True, 'showMessage': {'messageActionItem': {'additionalPropertiesSupport': True}}}, 'workspace': {'workspaceFolders': True, 'workspaceEdit': {'failureHandling': 'abort', 'documentChanges': True}, 'configuration': True, 'applyEdit': True, 'executeCommand': {}, 'didChangeConfiguration': {'dynamicRegistration': True}, 'symbol': {'dynamicRegistration': True, 'symbolKind': {'valueSet': [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26]}}}, 'experimental': {}}, 'clientInfo': {'version': '0.14.3', 'name': 'Sublime Text LSP'}, 'rootUri': None, 'workspaceFolders': None, 'rootPath': None}
:: <<< LSP-metals 1: {'message': 'Internal error.', 'code': -32603, 'data': 'java.util.concurrent.CompletionException: java.lang.NullPointerException\n\tat java.util.concurrent.CompletableFuture.encodeThrowable(CompletableFuture.java:292)\n\tat java.util.concurrent.CompletableFuture.completeThrowable(CompletableFuture.java:308)\n\tat java.util.concurrent.CompletableFuture.uniAccept(CompletableFuture.java:647)\n\tat java.util.concurrent.CompletableFuture$UniAccept.tryFire(CompletableFuture.java:632)\n\tat java.util.concurrent.CompletableFuture.uniAcceptStage(CompletableFuture.java:672)\n\tat java.util.concurrent.CompletableFuture.thenAcceptAsync(CompletableFuture.java:2001)\n\tat scala.concurrent.java8.FuturesConvertersImpl$CF.thenAccept(FutureConvertersImpl.scala:37)\n\tat org.eclipse.lsp4j.jsonrpc.RemoteEndpoint.handleRequest(RemoteEndpoint.java:279)\n\tat org.eclipse.lsp4j.jsonrpc.RemoteEndpoint.consume(RemoteEndpoint.java:190)\n\tat org.eclipse.lsp4j.jsonrpc.json.StreamMessageProducer.handleMessage(StreamMessageProducer.java:194)\n\tat org.eclipse.lsp4j.jsonrpc.json.StreamMessageProducer.listen(StreamMessageProducer.java:94)\n\tat org.eclipse.lsp4j.jsonrpc.json.ConcurrentMessageProcessor.run(ConcurrentMessageProcessor.java:113)\n\tat java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)\n\tat java.util.concurrent.FutureTask.run(FutureTask.java:266)\n\tat java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)\n\tat java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)\n\tat java.lang.Thread.run(Thread.java:748)\nCaused by: java.lang.NullPointerException\n\tat java.net.URI$Parser.parse(URI.java:3042)\n\tat java.net.URI.<init>(URI.java:588)\n\tat java.net.URI.create(URI.java:850)\n\tat scala.meta.internal.metals.MetalsLanguageServer.updateWorkspaceDirectory(MetalsLanguageServer.scala:276)\n\tat scala.meta.internal.metals.MetalsLanguageServer.$anonfun$initialize$2(MetalsLanguageServer.scala:680)\n\tat scala.concurrent.Future$.$anonfun$apply$1(Future.scala:659)\n\tat scala.util.Success.$anonfun$map$1(Try.scala:255)\n\tat scala.util.Success.map(Try.scala:213)\n\tat scala.concurrent.Future.$anonfun$map$1(Future.scala:292)\n\tat scala.concurrent.impl.Promise.liftedTree1$1(Promise.scala:33)\n\tat scala.concurrent.impl.Promise.$anonfun$transform$1(Promise.scala:33)\n\tat scala.concurrent.impl.CallbackRunnable.run(Promise.scala:64)\n\t... 3 more\n'}
:: --> LSP-metals shutdown(2): None
LSP-metals: 2021.01.14 13:40:46 INFO  shutting down Metals

[rwols]

Yeah it’s probably expecting a workspace folder. Open a folder with subl path/to/folder instead of a single file.

[devlaam]

On macos this would be

open "/Applications/Sublime Text.app" --args path/to/folder 

and indeed it opens up un 'untitled tab' at startup but it does not influence the setting of working dir as reported in the sublime logging. Note that in the GUI orientated macos world 'working directories' are not so relevant. Applications should no rely on that.

[tgodzik]

So this seems to be a problem:
workspace = AbsolutePath(Paths.get(URI.create(params.getRootUri))).dealias

and params.getRootUri seems to be null?

[rwols]

rootUri is allowed to be null as per protocol.

[tgodzik]

It seem it is, I will handle it separately.

[ckipp01]

I'm going to go ahead and turn this comment chain into an issue. Since indeed, that is valid, but we really need to think about how we handle the case where there is no rootUri. I'll add more details into the issue.

[ckipp01]

#2384

[tgodzik]

   * The rootUri of the workspace. Is null if no folder is open.
   * If both `rootPath` and `rootUri` are set, `rootUri` wins.

So it looks like no folder is actually open.

[tgodzik]

we'll have to at least handle the null, but I think we can make it a bit better on the Metals side.

[ckipp01]

Sorry to jump in here late, but just to make sure I'm following how this is reproduced, if opening Sublime this way just open a blank empty text file, why is the initialize even triggered?

[rwols]

There are language servers that don't care about workspaces, e.g. json, xml, and yaml language servers. It could be checked in LSP-metals whether there is at least one folder and prevent the server from starting.

[devlaam]

Hmm, this is hard to say. I had a scala file open at startup before. But now that this al works, this does not seem to trigger the bug any longer.

[ckipp01]

There are language servers that don't care about workspaces, e.g. json, xml, and yaml language servers. It could be checked in LSP-metals whether there is at least one folder and prevent the server from starting.

Gotcha. I thought even in those situations though they work on activation events, like filetypes. Either way, we can totally fix this case to give a better error message and instructions from the server.

[devlaam]

I am one step further. With the following startup procedure metals works.

1. Make sure all files are closed.
2. Shutdown Sublime
3. Open from the command line with open "/Applications/Sublime Text.app" --args path/to/folder (the working dir is still not set)
4. Now open your first scala file. This activates metals, it does not crash this time.

lsp-logging:

:: --> LSP-metals initialize(1): {'processId': 57019, 'workspaceFolders': [{'name': 'tests', 'uri': 'file:///..../tests'}], 'rootUri': 'file:///..../tests', 'capabilities': {'window': {'showMessage': {'messageActionItem': {'additionalPropertiesSupport': True}}, 'workDoneProgress': True}, 'experimental': {}, 'textDocument': {'rangeFormatting': {'dynamicRegistration': True}, 'documentHighlight': {'dynamicRegistration': True}, 'implementation': {'linkSupport': True, 'dynamicRegistration': True}, 'formatting': {'dynamicRegistration': True}, 'synchronization': {'willSave': True, 'willSaveWaitUntil': True, 'didSave': True, 'dynamicRegistration': True}, 'rename': {'dynamicRegistration': True}, 'codeAction': {'codeActionLiteralSupport': {'codeActionKind': {'valueSet': []}}, 'dynamicRegistration': True}, 'typeDefinition': {'linkSupport': True, 'dynamicRegistration': True}, 'definition': {'linkSupport': True, 'dynamicRegistration': True}, 'signatureHelp': {'signatureInformation': {'documentationFormat': ['markdown', 'plaintext'], 'parameterInformation': {'labelOffsetSupport': True}}, 'dynamicRegistration': True}, 'publishDiagnostics': {'relatedInformation': True}, 'declaration': {'linkSupport': True, 'dynamicRegistration': True}, 'colorProvider': {'dynamicRegistration': True}, 'documentSymbol': {'hierarchicalDocumentSymbolSupport': True, 'dynamicRegistration': True, 'symbolKind': {'valueSet': [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26]}}, 'completion': {'completionItem': {'snippetSupport': True}, 'completionItemKind': {'valueSet': [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25]}, 'dynamicRegistration': True}, 'hover': {'contentFormat': ['markdown', 'plaintext'], 'dynamicRegistration': True}, 'references': {'dynamicRegistration': True}}, 'workspace': {'workspaceFolders': True, 'didChangeConfiguration': {'dynamicRegistration': True}, 'workspaceEdit': {'documentChanges': True, 'failureHandling': 'abort'}, 'symbol': {'dynamicRegistration': True, 'symbolKind': {'valueSet': [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26]}}, 'configuration': True, 'applyEdit': True, 'executeCommand': {}}}, 'initializationOptions': {'inputBoxProvider': True}, 'clientInfo': {'name': 'Sublime Text LSP', 'version': '0.14.3'}, 'rootPath': '/..../tests'}
LSP-metals: 2021.01.14 14:37:12 INFO  logging to file /..../tests/.metals/metals.log
LSP-metals: 2021.01.14 14:37:12 INFO  Started: Metals version 0.9.8 in workspace '/..../tests' for client sublime.
LSP-metals: 2021.01.14 14:37:12 INFO  time: initialize in 0.31s
:: <<< LSP-metals 1: {'serverInfo': {'name': 'Metals', 'version': '0.9.8'}, 'capabilities': {'textDocumentSync': {'openClose': True, 'save': {'includeText': True}, 'change': 1}, 'completionProvider': {'triggerCharacters': ['.', '*'], 'resolveProvider': True}, 'hoverProvider': True, 'executeCommandProvider': {'commands': ['build-import', 'build-restart', 'build-connect', 'sources-scan', 'doctor-run', 'compile-cascade', 'compile-cancel', 'compile-clean', 'bsp-switch', 'generate-bsp-config', 'debug-adapter-start', 'goto', 'goto-position', 'new-scala-file', 'new-scala-project', 'goto-super-method', 'analyze-stacktrace', 'super-method-hierarchy', 'reset-choice', 'ammonite-start', 'ammonite-stop']}, 'documentSymbolProvider': True, 'documentHighlightProvider': True, 'renameProvider': {'prepareProvider': True}, 'documentRangeFormattingProvider': True, 'documentFormattingProvider': True, 'implementationProvider': True, 'signatureHelpProvider': {'triggerCharacters': ['(', '[', ',']}, 'referencesProvider': True, 'definitionProvider': True, 'foldingRangeProvider': True, 'workspaceSymbolProvider': True, 'codeActionProvider': {'codeActionKinds': ['quickfix', 'refactor', 'source.organizeImports']}, 'documentOnTypeFormattingProvider': {'moreTriggerCharacter': ['"'], 'firstTriggerCharacter': '\n'}, 'codeLensProvider': {'resolveProvider': False}}}
::  -> LSP-metals initialized: {}
::  -> LSP-metals textDocument/didOpen
LSP-metals: 2021.01.14 14:37:12 INFO  Attempting to connect to the build server...
LSP-metals: 2021.01.14 14:37:12 INFO  Selected port 5031
LSP-metals: 2021.01.14 14:37:13 WARN  no build target for: /..../tests/src/main/scala/....scala
:: <-- LSP-metals window/showMessageRequest(1): {'actions': [{'title': 'Import build'}, {'title': 'Not now'}, {'title': "Don't show again"}], 'message': 'New sbt workspace detected, would you like to import the build?', 'type': 3}
LSP-metals: 2021.01.14 14:37:12 INFO  Started Metals http server at http://127.0.0.1:5031
:: >>> LSP-metals 1: None
LSP-metals: 2021.01.14 14:37:26 INFO  tracing is disabled for protocol BSP, to enable tracing of incoming and outgoing JSON messages create an empty file at /Users/..../Library/Caches/org.scalameta.metals/bsp.trace.json
LSP-metals: 2021.01.14 14:37:26 INFO  time: connected to build server in 14s
LSP-metals: 2021.01.14 14:37:26 INFO  Connected to Build server v1.4.6-15-209c2a5c
:: <-  LSP-metals window/showMessage: {'type': 4, 'message': 'Importing build⠇'}
LSP-metals: 2021.01.14 14:37:27 ERROR Empty build targets. Expected at least one build target identifier.
:: <-  LSP-metals window/showMessage: {'type': 1, 'message': 'Missing valid Bloop build in /..../tests/.bloop.\n\n  1. Did you run bloop outside of the working directory of your build?\n     If so, change your current directory or point directly to your `.bloop` directory via `--config-dir`.\n\n  2. Did you forget to generate configuration files for your build?\n     Check the installation instructions https://scalacenter.github.io/bloop/setup\n    '}
LSP-metals: 2021.01.14 14:37:27 ERROR Empty build targets. Expected at least one build target identifier.
LSP-metals: 2021.01.14 14:37:27 ERROR Empty build targets. Expected at least one build target identifier.
:: <-  LSP-metals window/showMessage: {'type': 4, 'message': 'Indexing⠇'}
LSP-metals: 2021.01.14 14:37:27 INFO  time: indexed workspace in 0.55s
LSP-metals: 2021.01.14 14:37:27 WARN  no build target for: /..../tests/src/main/scala/....scala
:: --> LSP-metals textDocument/documentHighlight(2): {'textDocument': {'uri': 'file:///..../tests/src/main/scala/....scala'}, 'position': {'line': 20, 'character': 70}}
:: <<< LSP-metals 2: []
:: <-  LSP-metals window/showMessage: {'type': 4, 'message': '🚀 Indexing complete!'}
LSP-metals: 2021.01.14 14:37:28 INFO  no build target: using presentation compiler with only scala-library

(removed some privacy related chars)

So the problem seems to be that files that are already present before the metals is started somehow make it impossible to determine the working directory. After crash, opening up a new file it too late. Now i have a .metals directory in my directory. (This is interesting, since the file i openen was a few levels deeper. Somehow metals or sublime was able to determine which folder is the right one, or it uses the one given on startup).

[devlaam]

Okay guys, i have metals running now, but still no build target. However, i don't think we should solve that in this discussion. Therefore i will change the title to something more appropriate, and marked my former post as answer.

However, although i wrote that answer, it is not my merit. Only due to your swift and adequate help i was able to find this. Therefore i am grateful. Thank you @ayoub-benali @tgodzik @rwols !

[ayoub-benali]

@devlaam I am glad it works now.

Totally optional but for a better LSP support it recommend upgrading to ST4, see https://discord.com/channels/280102180189634562/650695903446827011

And if you have questions/ issues regarding LSP join this channel: https://discord.com/channels/280102180189634562/645268178397560865