Error: "Request textDocument/documentSymbol failed"

[Majkel1999]

When working with a .tex document, in uncertain circumstances, the error Request textDocument/documentSymbol failed shows up.

This error mostly shows up when creating a new .tex file, which is a part of a bigger document, and starting with a directive such as `\chapter{}'. After saving the document, or when using autosave, the above error is displayed.

[Error - 9:56:14 AM] Request textDocument/documentSymbol failed.
Error: name must not be falsy
	at t.validate (c:\Users\<Redacted>\AppData\Local\Programs\Microsoft VS Code\resources\app\out\vs\workbench\api\node\extensionHostProcess.js:94:25900)
	at new t (c:\Users\<Redacted>\AppData\Local\Programs\Microsoft VS Code\resources\app\out\vs\workbench\api\node\extensionHostProcess.js:94:26195)
	at V (c:\Users\<Redacted>\.vscode\extensions\efoerster.texlab-5.4.0-win32-x64\dist\extension.js:1:213015)
	at c (c:\Users\<Redacted>\.vscode\extensions\efoerster.texlab-5.4.0-win32-x64\dist\extension.js:1:251012)
	at t.map (c:\Users\<Redacted>\.vscode\extensions\efoerster.texlab-5.4.0-win32-x64\dist\extension.js:1:251098)
	at Object.asDocumentSymbols (c:\Users\<Redacted>\.vscode\extensions\efoerster.texlab-5.4.0-win32-x64\dist\extension.js:1:220833)
	at i (c:\Users\<Redacted>\.vscode\extensions\efoerster.texlab-5.4.0-win32-x64\dist\extension.js:1:159487)
	at async n.provideDocumentSymbols (c:\Users\<Redacted>\AppData\Local\Programs\Microsoft VS Code\resources\app\out\vs\workbench\api\node\extensionHostProcess.js:98:32515)

TexLab custom settings:

    "texlab.build.executable": "tectonic",
    "texlab.build.args": [
      "-X",
      "compile",
      "%f",
      "-Z=shell-escape",
      "--synctex",
      "--keep-logs",
      "--keep-intermediates"
    ],
    "texlab.formatterLineLength": 120,

Operating System:

Edition	Windows 10 Education
Version	21H2
OS build	19044.2486
Experience	Windows Feature Experience Pack 120.2212.4190.0

[Majkel1999]

The same error happens each time you add a new section, without a title. To reproduce:

1. Open a valid .tex file - it can be the main file, or a part of a bigger project.
2. Write \section{}
3. The error shows up

Due to how VSCode autocompletes the second bracket in {} the error shows up each time you start writing.

EDIT: When copying and pasting a section with a name already in it, the error is not thrown. Example: \section{abc}

[pfoerster]

@Majkel1999 Thanks for debugging this issue! f8baa93 fixes problem.

[Majkel1999]

Perfect! Thanks and great work on this extension.