Live-share: Red lines not communicated between the share session

[johnpapa]

macos 
VS Code - Version 1.24.0-insider (1.24.0-insider)

When connecting to another person's liveshare, I do not see the red squigglies and code tips that they see. Also, I get red lines where I shouldn't. (i am trying to narrow this down now but wanted to open the issue in case anyone else sees this too)

cc @craigshoemaker

[lostintangent]

@johnpapa Thanks for reporting this! Was the “host” in VS or VS Code? What kind of project was it? Node.js? Also, do you recall whether the errors you weren’t seeing were from a specific source? (e.g. ESLint, TypeScript).

The current expectation is that guests can see all errors that the host sees, so if you’re seeing otherwise, that would be a bug, and may be an issue/limitation with a specific extension. We implemented our remote language services in a “universal” way, but there are lingering issues with certain languages/linters/etc. that we need to address.

[johnpapa]

Thanks for the quick reply.

• I was in VS Code (stable) on macos.
• The host was in VS Code (stable) on Windows 10.
• The app is an electron app (with node and angular).

I believe the errors were mostly TypeScript errors. For example when we had the wrong types, the host would see the errors, but I would not.

@craigshoemaker was the host and may have more info

[craigshoemaker]

Correct. Many of of the squigglies were TS-related.

[lostintangent]

@craigshoemaker Which version of VS Code are you running? 1.22? I believe the APIs we need to sync errors only appeared in 1.23. So that may be the issue?

I just quickly tested this out between Windows and macOS, using VS Code Stable (1.23.1) and Insiders (1.24.0), and all the various permutations, and errors seem to be shared correctly with the guest. I even used an Angular-based Electron app + TypeScript, and things seemed to work as expected.

We'll keep looking. Thanks again!

[craigshoemaker]

@lostintangent My version is 1.23.1. I am trying to think of anything else that could be relevant. This app uses Webpack to build (although I doubt that has any bearing on VSCode). By any chance would having a screen share running at the same time as the liveshare interfere with what appears during liveshare? We had a Skype for Business screen share going at the same time as the liveshare so John could see the results in Electron.

If you want, I could share with you and see if we can replicate.

[sentience]

I've seen this in sessions I have participated in this week, both as guest and host. As host, the problems are up-to-date and correct, but as guest, problems that appear never disappear. When the host fixes a compiler error, for example, the problem and its red underline disappears from the host's editor views, but they remain in the guest's editor views.

We're seeing this with compiler errors from the Elm language support extension, as well as the Flow extension, for what it's worth. It doesn't seem to be specific to any particular extension.

[lostintangent]

@sentience Thanks for letting us know! We haven’t been able to repro this, so I’ll try Elm and Flow specifically to see whether we can figure out what’s going on. Errors are supposed to be properly synchronized, so if they’re not, that’s a bug we want to fix ASAP.

Just to confirm: are you referring to errors that show up/go away while typing? Or errors that come and go after running a task/compile step?

// CC @daytonellwanger

[sentience]

Flow errors appear and disappear while typing. Elm errors only update at Save. Both seem not to be synchronised properly.

We've tried having the guest disconnect from the host and reconnect, but the stale problems remain when they do.

[lostintangent]

@sentience I investigated the Elm bug, and just sent a PR to their VS Code extension to resolve it. I was able to repro the issue, so I appreciate you reporting this!

Additionally, the Flow issue stems from the same root cause as Elm, which I believe is actually a VS Code bug. I reported an issue with them and will keep you posted on updates. Thanks!

[lostintangent]

@sentience @jasononiel The fix for this went in to VS Code last night, and so if you're running Insiders, and update to the latest build, your Elm/Flow errors should synchronize correctly. Otherwise, it will go in to the next release of VS Code Stable. Thanks again for reporting this issue!