Formatting a Java file sometimes eats parts of the code

[Artur-]

This is similar to a bug that existed in Eclipse maybe 5 or 10 years ago.

Every now and then when you press format, part of the code is deleted. This is really super bad for any IDE, especially when you have auto format on save turned on. "Done with your changes? Sure, let me just save and commit. Why did you commit broken code, it doesn't even compile? %#€""

It seems like the formatter and also code highlighting gets out of sync with reality when this happens, e.g. in this example you can see that return is incorrectly colored.

formatting-out-of-sync.mov

Environment

• Operating System: mac os Big Sur
• JDK version: 17
• Visual Studio Code version: 1.61.1
• Java extension version: 0.82.0

Steps To Reproduce

1. Use VS Code until it happens... there is no reliable way as far as I know

[0dinD]

I'm pretty sure I know the cause of the desynced highlighting, see eclipse-jdtls/eclipse.jdt.ls#1918. If the outdated AST is also used by the formatter, that could explain what you're seeing.

But I haven't been able to reproduce any issues with formatting yet, so I'm not entirely sure. Does the formatter only eat parts of the code if you see desynced highlighting, like in your clip above? As in, have you ever seen it happen when formatting a document that has "correct" highlighting?

Also, can you share your formatter settings and the code you're working on (or any structurally equivalent code)? Since I know how to reproduce the desynced tokens, I could try applying code formatting using your settings after that, to see if the issues are related.

And does the highlighting restore itself after you type more characters? Or is it broken until you reopen the document or restart VS Code?

[Artur-]

Can't say if it is always connected to incorrect highlighting or not as I haven't really been paying attention to it. I do think highlighting is off in many of the cases but not sure if it always is.

What I do know is that it happens almost daily to me. I work on different projects and have seen it in all of them so I doubt it is connected to the code itself.

The default formatter settings is used in at least one of the projects.

This is most noticeable when pressing save and instead of saving the file you save a broken version when it runs the formatter on save. Sometimes pressing save several times deletes more and more of the code.

[0dinD]

Actually I don't think it's related to eclipse-jdtls/eclipse.jdt.ls#1918, because it seems like the formatter doesn't use the shared AST provider.

If you can't share the projects, do you know of an open-source project where you can reproduce the issue? I can't reproduce this issue, but if it has anything to do with a race condition it's just a matter of getting the timings right, at which point things like project size and hardware specs etc. might start to matter. If you know of any conditions that affect the likelihood of reproducing the issue (apart from format on save, which I tried), that would be helpful.

[snjeza]

@Artur- Could you show your settings.json and the extensions you are using?

[Artur-]

This is what I saw today

codeformatting2.mov

Apparently something had gone wrong already before capturing the video because the methods are missing a few LOC and brackets.

This was with this project https://github.com/vaadin/flow but having only the folder https://github.com/vaadin/flow/tree/master/flow-tests/test-frontend/vite-basics open in this VS Code instance (some other modules in other VS Code instances).

Formatting triggered by saving but as there were some changes done outside the IDE, save didn't actually save but only formatted.

Might or might not be related to running mvn commands in a terminal while having VS Code running

[Artur-]

In exthost.log I see a lot of the following from around that time. Can't say if they are related though

[2021-10-26 09:56:42.636] [exthost] [error] Error: 
	at /Users/artur/.vscode/extensions/redhat.java-1.0.0/dist/extension.js:2:894993
	at /Users/artur/.vscode/extensions/redhat.java-1.0.0/dist/extension.js:2:895287
	at Immediate.<anonymous> (/Users/artur/.vscode/extensions/redhat.java-1.0.0/dist/extension.js:2:895652)
	at processImmediate (internal/timers.js:461:21) java.execute.workspaceCommand

[Artur-]

settings.json in .vscode in that project is

{
    "lit-plugin.strict": true
}

$ ls ~/.vscode/extensions
adpyke.vscode-sql-formatter-1.4.4
asciidoctor.asciidoctor-vscode-2.8.9
bierner.lit-html-1.11.1
dawhite.mustache-1.1.1
donjayamanne.javadebugger-0.1.5
dotjoshjohnson.xml-2.5.1
eamodio.gitlens-11.6.0
esbenp.prettier-vscode-9.0.0
foxundermoon.shell-format-7.1.0
gabrielbb.vscode-lombok-1.0.1
gitpod.gitpod-desktop-0.0.27
joaompinto.asciidoctor-vscode-2.8.0
mathiasfrohlich.kotlin-1.7.1
microprofile-community.mp-rest-client-generator-vscode-ext-0.1.2
microprofile-community.mp-starter-vscode-ext-0.2.7
microprofile-community.vscode-microprofile-pack-0.1.2
mrmlnc.vscode-json5-1.0.0
ms-azuretools.vscode-docker-1.17.0
ms-kubernetes-tools.vscode-kubernetes-tools-1.3.3
ms-vscode-remote.remote-containers-0.194.3
ms-vscode-remote.remote-ssh-0.65.8
ms-vscode-remote.remote-ssh-edit-0.65.8
ms-vsliveshare.vsliveshare-1.0.4836
payara.payara-vscode-1.1.1
pivotal.vscode-boot-dev-pack-0.1.0
pivotal.vscode-concourse-1.28.0
pivotal.vscode-manifest-yaml-1.28.0
pivotal.vscode-spring-boot-1.28.0
redhat.fabric8-analytics-0.3.3
redhat.java-1.0.0
redhat.vscode-commons-0.0.6
redhat.vscode-yaml-0.22.0
richie5um2.vscode-sort-json-1.20.0
runem.lit-plugin-1.2.1
tberman.json-schema-validator-0.1.0
vaadin.studio-0.1.1
visualstudioexptteam.vscodeintellicode-1.2.14
vscjava.vscode-java-debug-0.36.0
vscjava.vscode-java-dependency-0.18.8
vscjava.vscode-java-pack-0.18.5
vscjava.vscode-java-test-0.32.0
vscjava.vscode-maven-0.34.0
vscjava.vscode-spring-boot-dashboard-0.2.0
vscjava.vscode-spring-initializr-0.7.0

[Artur-]

Now incorrect highlighting was triggered by undo but formatting still is correct

undo.mov

[Artur-]

... but formatting starts to break then after adding a new method

[snjeza]

@Artur- could you show ~/.config/Code/User/settings.json?
Could you disable all other extensions and try to reproduce the issue?

[Artur-]

I do not have any ~/.config/Code/User/settings.json file. I can try disabling extensions and see if it changes anything

[fabio-porcedda]

I had the same problem, disabling and re-enabling all other extensions seems to have fixed the issue.

[zodiake]

3 years past no progress...