"typescript.inlayHints.includeInlayParameterNameHints": "all" breaks inference with dangling commas

[Klaster1]

How to reproduce:

1. Install TypeScript 4.8.4 as a project dependency.
2. Enable set "typescript.inlayHints.includeInlayParameterNameHints" to "all".
3. Checks the inferred type for nums:

class Bad {
	nums = combineLatest([of(1), of(2), of(3)]).pipe(
		map(([a, b, c]) => a + b + c), // <- trailing comma
	)
}

Reproducer: tslangserver-report.zip.

Expected:
The type is inferred as Observable<number>.

Observed:
nums infers to Observable<unknown>.

Notes:
I'm using the service via the https://github.com/sublimelsp/LSP-typescript in Sublime Text 4. Disabling the setting or removing the comma fixes the inference. VSCode with language server version set to 4.8.4 infers everything correctly. This is mildly annoying as Prettier adds dangling commas by default and I can't change the project TS version yet. I can point the server to use TS 5, but I figured the bug's worth reporting anyway,

[rchl]

I see the same for both cases.

Also same in VSCode.
Is there something to your setup that makes it reproducible?

[Klaster1]

Perhaps I should have structered the example better, my bad. Try this:

const bad = new Bad()
const nums: Observable<number> = bad.nums

My results:

[rchl]

Please provide here the output of LSP: Troubleshoot server command. You are setting a bunch of extra settings that you haven't mentioned and I don't want to figure out what to set from the screenshot.

Also you are using TS plugins which is another variable. Have you tried if this reproduces with a minimal user overrides?

[Klaster1]

The same happens when only setting the "includeInlayParameterNameHints": "all":

{
	"settings": {
		"typescript.inlayHints.includeInlayParameterNameHints": "all", // none | literals | all
	}
}

Troubleshoot output with the minimal LSP-typescript config

## Server Configuration - command ```json [ "${node_bin}", "${server_path}", "--stdio" ]

• shell command

"C:\Program Files\nodejs\node.EXE" "C:\Users\Klaster_1\AppData\Local\Sublime Text 3\Package Storage\LSP-typescript\18.15.0\typescript-language-server\node_modules\typescript-language-server\lib\cli.mjs" --stdio

• selector

source.js, source.jsx, source.ts, source.tsx

• priority_selector

source.js, source.jsx, source.ts, source.tsx

• init_options

{
  "completionDisableFilterText": true, 
  "disableAutomaticTypingAcquisition": false, 
  "locale": "en", 
  "maxTsServerMemory": 0, 
  "npmLocation": "", 
  "plugins": [], 
  "preferences": {
    "allowIncompleteCompletions": true, 
    "allowRenameOfImportPath": true, 
    "allowTextChangesInNewFiles": true, 
    "autoImportFileExcludePatterns": [], 
    "disableSuggestions": false, 
    "displayPartsForJSDoc": true, 
    "generateReturnInDocTemplate": true, 
    "importModuleSpecifierEnding": "auto", 
    "importModuleSpecifierPreference": "shortest", 
    "includeAutomaticOptionalChainCompletions": true, 
    "includeCompletionsForImportStatements": true, 
    "includeCompletionsForModuleExports": true, 
    "includeCompletionsWithClassMemberSnippets": true, 
    "includeCompletionsWithInsertText": true, 
    "includeCompletionsWithObjectLiteralMethodSnippets": true, 
    "includeCompletionsWithSnippetText": true, 
    "includePackageJsonAutoImports": "auto", 
    "jsxAttributeCompletionStyle": "auto", 
    "lazyConfiguredProjectsFromExternalProject": false, 
    "organizeImportsAccentCollation": true, 
    "organizeImportsCaseFirst": false, 
    "organizeImportsCollation": "ordinal", 
    "organizeImportsCollationLocale": "en", 
    "organizeImportsIgnoreCase": "auto", 
    "organizeImportsNumericCollation": false, 
    "providePrefixAndSuffixTextForRename": true, 
    "provideRefactorNotApplicableReason": true, 
    "quotePreference": "auto", 
    "useLabelDetailsInCompletionEntries": true
  }, 
  "tsserver": {
    "logDirectory": "", 
    "logVerbosity": "off", 
    "path": "", 
    "trace": "off", 
    "useSyntaxServer": "auto"
  }
}

• settings

{
  "diagnostics": {
    "ignoredCodes": []
  }, 
  "implicitProjectConfiguration": {
    "checkJs": false, 
    "experimentalDecorators": false, 
    "module": "ESNext", 
    "strictFunctionTypes": true, 
    "strictNullChecks": true, 
    "target": "ES2020"
  }, 
  "javascript": {
    "format": {
      "insertSpaceAfterCommaDelimiter": true, 
      "insertSpaceAfterConstructor": false, 
      "insertSpaceAfterFunctionKeywordForAnonymousFunctions": true, 
      "insertSpaceAfterKeywordsInControlFlowStatements": true, 
      "insertSpaceAfterOpeningAndBeforeClosingEmptyBraces": false, 
      "insertSpaceAfterOpeningAndBeforeClosingJsxExpressionBraces": false, 
      "insertSpaceAfterOpeningAndBeforeClosingNonemptyBraces": true, 
      "insertSpaceAfterOpeningAndBeforeClosingNonemptyBrackets": false, 
      "insertSpaceAfterOpeningAndBeforeClosingNonemptyParenthesis": false, 
      "insertSpaceAfterOpeningAndBeforeClosingTemplateStringBraces": false, 
      "insertSpaceAfterSemicolonInForStatements": true, 
      "insertSpaceAfterTypeAssertion": false, 
      "insertSpaceBeforeAndAfterBinaryOperators": true, 
      "insertSpaceBeforeFunctionParenthesis": false, 
      "insertSpaceBeforeTypeAnnotation": false, 
      "placeOpenBraceOnNewLineForControlBlocks": false, 
      "placeOpenBraceOnNewLineForFunctions": false, 
      "semicolons": "ignore", 
      "trimTrailingWhitespace": true
    }, 
    "inlayHints": {
      "includeInlayEnumMemberValueHints": false, 
      "includeInlayFunctionLikeReturnTypeHints": false, 
      "includeInlayFunctionParameterTypeHints": false, 
      "includeInlayParameterNameHints": "none", 
      "includeInlayParameterNameHintsWhenArgumentMatchesName": false, 
      "includeInlayPropertyDeclarationTypeHints": false, 
      "includeInlayVariableTypeHints": false, 
      "includeInlayVariableTypeHintsWhenTypeMatchesName": false
    }
  }, 
  "statusText": "$version, $source", 
  "typescript": {
    "format": {
      "insertSpaceAfterCommaDelimiter": true, 
      "insertSpaceAfterConstructor": false, 
      "insertSpaceAfterFunctionKeywordForAnonymousFunctions": true, 
      "insertSpaceAfterKeywordsInControlFlowStatements": true, 
      "insertSpaceAfterOpeningAndBeforeClosingEmptyBraces": false, 
      "insertSpaceAfterOpeningAndBeforeClosingJsxExpressionBraces": false, 
      "insertSpaceAfterOpeningAndBeforeClosingNonemptyBraces": true, 
      "insertSpaceAfterOpeningAndBeforeClosingNonemptyBrackets": false, 
      "insertSpaceAfterOpeningAndBeforeClosingNonemptyParenthesis": false, 
      "insertSpaceAfterOpeningAndBeforeClosingTemplateStringBraces": false, 
      "insertSpaceAfterSemicolonInForStatements": true, 
      "insertSpaceAfterTypeAssertion": false, 
      "insertSpaceBeforeAndAfterBinaryOperators": true, 
      "insertSpaceBeforeFunctionParenthesis": false, 
      "insertSpaceBeforeTypeAnnotation": false, 
      "placeOpenBraceOnNewLineForControlBlocks": false, 
      "placeOpenBraceOnNewLineForFunctions": false, 
      "semicolons": "ignore", 
      "trimTrailingWhitespace": true
    }, 
    "inlayHints": {
      "includeInlayEnumMemberValueHints": false, 
      "includeInlayFunctionLikeReturnTypeHints": false, 
      "includeInlayFunctionParameterTypeHints": false, 
      "includeInlayParameterNameHints": "all", 
      "includeInlayParameterNameHintsWhenArgumentMatchesName": false, 
      "includeInlayPropertyDeclarationTypeHints": false, 
      "includeInlayVariableTypeHints": false, 
      "includeInlayVariableTypeHintsWhenTypeMatchesName": false
    }
  }
}

• env

{
  "PATH": "C:\\Program Files\\nodejs;C:\\Program Files\\nodejs;"
}

Active view

• File name

C:\dev\ggstuff\typescript-language-server-754\index.ts

• Settings

{
  "auto_complete_selector": "meta.tag, source - comment - string.quoted.double.block - string.quoted.single.block - string.unquoted.heredoc", 
  "lsp_active": true, 
  "syntax": "Packages/JavaScript/TypeScript.sublime-syntax"
}

• base scope

source.ts

Project / Workspace

• folders

[
  "C:\\dev\\ggstuff\\typescript-language-server-754"
]

• is project: True
• project data:

{
  "folders": [
    {
      "path": "."
    }
  ]
}

LSP configuration

{
  "completion_insert_mode": "insert", 
  "document_highlight_style": "background", 
  "hover_highlight_style": "background", 
  "inhibit_snippet_completions": true, 
  "inhibit_word_completions": true, 
  "log_debug": true, 
  "lsp_code_actions_on_save": {
    "source.organizeImports": false
  }, 
  "lsp_format_on_save": false, 
  "semantic_highlighting": false, 
  "show_code_lens": "phantom", 
  "show_inlay_hints": true, 
  "show_references_in_quick_panel": true
}

System PATH

• C:\Program Files\AdoptOpenJDK\jdk-11.0.11.9-hotspot\bin
• C:\Program Files (x86)\Common Files\Oracle\Java\javapath
• C:\Program Files\AdoptOpenJDK\jdk-8.0.292.10-hotspot\bin
• C:\Python38\Scripts\
• C:\Python38\
• C:\Program Files (x86)\Common Files\Microsoft Shared\Windows Live
• C:\Program Files (x86)\Intel\iCLS Client\
• C:\Program Files\Intel\iCLS Client\
• C:\Program Files (x86)\AMD APP\bin\x86_64
• C:\Program Files (x86)\AMD APP\bin\x86
• C:\Program Files (x86)\ATI Technologies\ATI.ACE\Core-Static
• c:\Program Files\7-Zip\
• c:\Program Files\OpenSSL-Win64\bin\
• C:\Program Files (x86)\PuTTY\
• c:\Program Files (x86)\Java\jre7\bin\
• C:\Program Files\cURL\bin
• c:\Program Files (x86)\GnuWin32\bin\
• c:\Program Files\GraphicsMagick-1.3.19-Q8\
• c:\mongo\bin\
• C:\Program Files (x86)\Heroku\bin
• C:\Program Files (x86)\git\cmd
• C:\Program Files\Intel\Intel(R) Management Engine Components\DAL
• C:\Program Files (x86)\Intel\Intel(R) Management Engine Components\DAL
• C:\Program Files\Intel\Intel(R) Management Engine Components\IPT
• C:\Program Files (x86)\Intel\Intel(R) Management Engine Components\IPT
• C:\Program Files (x86)\AMD\ATI.ACE\Core-Static
• c:\Program Files\Sublime Text 3\
• c:\Program Files\ConEmu\
• C:\WINDOWS\system32
• C:\WINDOWS
• C:\WINDOWS\System32\Wbem
• C:\WINDOWS\System32\WindowsPowerShell\v1.0\
• C:\WINDOWS\system32
• C:\WINDOWS
• C:\WINDOWS\System32\Wbem
• C:\WINDOWS\System32\WindowsPowerShell\v1.0\
• C:\WINDOWS\System32\OpenSSH\
• C:\ProgramData\chocolatey\bin
• C:\Program Files\dotnet\
• C:\Program Files\Git\cmd
• C:\Program Files\Git\mingw64\bin
• C:\Program Files\Git\usr\bin
• C:\Program Files\WireGuard\
• C:\Program Files\Docker\Docker\resources\bin
• C:\Program Files\nodejs\
• C:\Program Files\PowerShell\7\
• C:\Users\Klaster_1\AppData\Local\Programs\Python\Python310\Scripts\
• C:\Users\Klaster_1\AppData\Local\Programs\Python\Python310\
• C:\Users\Klaster_1\scoop\shims
• C:\Program Files (x86)\Common Files\Microsoft Shared\Windows Live
• C:\Windows\System32
• c:\Program Files\FFmpeg\bin\
• c:\Program Files\cURL\bin\
• C:\Program Files\Git\bin\
• c:\Users\Klaster_1\AppData\Local\Android\android-sdk\platform-tools\
• C:\Users\Klaster_1\AppData\Local\Microsoft\WindowsApps
• C:\Users\Klaster_1\AppData\Local\Programs\oh-my-posh\bin
• c:\Program Files\mvn\bin\
• C:\Users\Klaster_1\AppData\Local\Microsoft\WinGet\Links
• c:\Program Files (x86)\ClockworkMod\Universal Adb Driver\
• c:\Users\Klaster_1\Downloads\gradle-8.0-bin\gradle-8.0\bin\
• C:\Users\Klaster_1\AppData\Roaming\npm
• C:\Users\Klaster_1\AppData\Local\Programs\Microsoft VS Code\bin
• C:\Users\Klaster_1\AppData\Local\Microsoft\WindowsApps

</details>

[rchl]

Doesn't reproduce here unfortunately. I'm on Mac though. Maybe there is some Windows-specific issue here. I could test this when I have some more time.

[Klaster1]

Wait, but your screenshot reproduces the issue precisely. Did you try removing the dangling comma? Or was it shot on Windows?

[rchl]

Oh. :)

That was mac but I see now why it wasn't reproducing before. It doesn't reproduce when semantic_highlighting is enabled.

If you set:

"editor.semanticHighlighting.enabled": false

in VSCode then it will also reproduce there.

It also doesn't reproduce in any case with TS 5.0.4 (for example) so I think this needs to be treated as a TypeScript bug that is already fixed and not an issue specific to this server.