Inside <style> blocks in html files: Error while computing completions for; Cannot read property 'label' of undefined

[joshunger]

Issue Type: Bug

[Error - 6:12:13 AM] Error while computing completions for file:///Users/junger/dev/private/kitchensink/src/index.html: Cannot read property 'label' of undefined
TypeError: Cannot read property 'label' of undefined
    at Object.<anonymous> (/Applications/Visual Studio Code - Insiders.app/Contents/Resources/app/extensions/html-language-features/server/out/htmlServerMain.js:323:85)
    at step (/Applications/Visual Studio Code - Insiders.app/Contents/Resources/app/extensions/html-language-features/server/out/htmlServerMain.js:36:23)
    at Object.next (/Applications/Visual Studio Code - Insiders.app/Contents/Resources/app/extensions/html-language-features/server/out/htmlServerMain.js:17:53)
    at fulfilled (/Applications/Visual Studio Code - Insiders.app/Contents/Resources/app/extensions/html-language-features/server/out/htmlServerMain.js:8:58)
    at <anonymous>

VS Code version: Code - Insiders 1.23.0-insider (fc389d2, 2018-04-05T05:10:30.542Z)
OS version: Darwin x64 17.4.0

System Info

Item	Value
CPUs	Intel(R) Core(TM) i5-7267U CPU @ 3.10GHz (4 x 3100)
GPU Status	2d_canvas: enabled checker_imaging: disabled_off flash_3d: enabled flash_stage3d: enabled flash_stage3d_baseline: enabled gpu_compositing: enabled multiple_raster_threads: enabled_on native_gpu_memory_buffers: enabled rasterization: enabled video_decode: enabled video_encode: enabled webgl: enabled webgl2: enabled
Load (avg)	2, 2, 2
Memory (System)	16.00GB (0.25GB free)
Process Argv	/Applications/Visual Studio Code - Insiders.app/Contents/MacOS/Electron ./
Screen Reader	no
VM	0%

Extensions (10)

Extension	Author (truncated)	Version
sort-lines	Tyr	1.6.0
vscode-eslint	dba	1.4.8
prettier-vscode	esb	1.2.2
python	ms-	2018.3.1
java	red	0.22.0
vscode-fileutils	sle	2.8.1
vscode-java-debug	vsc	0.8.0
vscode-java-pack	vsc	0.3.0
vscode-java-test	vsc	0.5.0
vscode-maven	vsc	0.6.0

I don't have repro steps but if you can tell me context I can estimate the issue and repro steps.

[vscodebot]

(Experimental duplicate detection)
Thanks for submitting this issue. Please also check if it is already covered by an existing one, like:

• Rename: Cannot read property 'startLineNumber' of undefined (#47276)

[fuzzykiller]

This issue also occurs on version Version 1.22.1 (950b8b0).

I think it’s a race condition that happens when I delete text VS Code is trying to provide a suggestion with. However, I don’t have reliable repro steps. It appears to happen frequently when editing CSS embedded in a <style> tag in a plain HTML document.

[joshunger]

@fuzzykiller same here, I was editing CSS in a <style> in a .html document

[ramya-rao-a]

@aeschli This is coming from https://github.com/Microsoft/vscode/blob/master/extensions/css-language-features/server/src/cssServerMain.ts#L198

[aeschli]

@ramya-rao-a htmlServerMain.js:323 is
if (hexColorRegex.test(emmetCompletionList.items[0].label) && result.items.some(function (x) { return x.label === emmetCompletionList.items[0].label; })) {

Are you sure about https://github.com/Microsoft/vscode/blob/master/extensions/css-language-features/server/src/cssServerMain.ts#L198? What's wrong there?

[aeschli]

Looks like #47384

[joshunger]

@aeschli thanks let us know if you need any help

[ramya-rao-a]

Sorry about that @aeschli, yes this is coming from htmlServerMain and is same as #47384

I'll add the null/undefined check, but I am curious as to what conditions lead to this error as I cannot backtrack and see any case where the completion items is not an array in a completion list.

@joshunger Can you repro this consistently? If yes, then can you provide sample code and steps?

[joshunger]

@ramya-rao-a no

[fuzzykiller]

@ramya-rao-a Just spam Ctrl+Space and Backspace (or Ctrl+Backspace because it's easier to keep pressing Ctrl) inside a <style> element. It's quite reliable.

It does not happen in CSS files, only in HTML files.

[ramya-rao-a]

Thanks @fuzzykiller

Steps to verify fix:
Inside a <style> block in an html file have a css rule as below:

<style>
        body {
            background-color: #000000;
            disp
        }
    </style>

• Type l after the disp. You should get suggestions and not errors in the output channel for HTML language server
• Trigger suggestions after typing either font- or background- (basically any css property that has a - in the middle, type only till the - and then esc to remove existing suggestions and then trigger suggestions manually). You should get suggestions and not errors in the output channel for HTML language server

[joshunger]

Thanks 👏 @ramya-rao-a

[dmbdesignpdx]

Hi,
I'm still getting errors in the output channel with the fix suggestion.

Inside an inline <style> in an .html file, if I start typing...

#test {
   border-
}

then escape the suggestions, and continue typing...

#test {
   border-b
}

I get the error.

It also happens during this scenario:

1. I type the whole property without any deletions or select the suggestion to auto-complete
2. delete the characters until the hyphen
3. start retyping the property

This seems to be consistent only with the first letter of the second part of a hyphenated property. For example:

• border-t for top or
• border-c for collapse
  will throw the error without any suggestions for auto-complete.

BUT if I start off with a letter that is post-first letter, i.e.: border-a, border-k, border-y, etc. it will NOT throw an error and will provide me with suggestions to auto-complete.

The error:

[Error - 23:38:11] Error while computing completions for untitled:Untitled-1: Cannot read property 'label' of undefined
TypeError: Cannot read property 'label' of undefined
    at Object.<anonymous> (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/html-language-features/server/out/htmlServerMain.js:323:84)
    at step (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/html-language-features/server/out/htmlServerMain.js:36:23)
    at Object.next (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/html-language-features/server/out/htmlServerMain.js:17:53)
    at fulfilled (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/html-language-features/server/out/htmlServerMain.js:8:58)
    at <anonymous>

My info:

VS Code version: Code 1.22.1 (950b8b0, 2018-04-06T00:21:13.607Z)
OS version: Darwin x64 17.5.0

System Info

Item	Value
CPUs	Intel(R) Core(TM) i7-4750HQ CPU @ 2.00GHz (8 x 2000)
Load (avg)	3, 2, 2
Memory (System)	8.00GB (0.30GB free)
Process Argv	/Applications/Visual Studio Code.app/Contents/MacOS/Electron
Screen Reader	no
VM	0%

Extensions: none (6 theme extensions excluded)

Hope that made sense; please let me know!

[ramya-rao-a]

@dmbdesignpdx You are on stable VS Code version 1.22.1 The fix is currently available in the Insiders build of 1.23. The fix will also be shipped in stable VS Code version 1.22.2 in a few days