Undo defect? Undo make my file back to status when I open it


Background: I was writing a latex file on my MAC using Atom last night. And I also opened that same file in my Windows machine using CTex. That file is in my dropbox, so once I save changes in my MAC, I can get it on my Win(I don’t know why I have to do this last night, but this is how the issue occurred).

The issue was happened in this way: I opened up the Atom on maybe 7pm, and the file is always opening in my Windows machine( actually I didn’t do anything on my win machine, only occasionally refresh that file). At 11 pm or so, I was copy and paste some codes in order to get a right figures order in my latex file, and I didn’t satisfied with my latest change so I hit the undo.

Then it happened, at the first glance I think my Mac is stuck for some reason, because the Atom just stuck there(my Mac is 16GB RAM, I don’t think an undo will make things crash). I was afraid about losing anything so I hit the shortcut of save file in Atom even if the Atom is stuck there.

After a while, maybe 30 sec, I found the terrible thing is that my file return(undo) to the state when it is 7pm when I open it, and I just hit the save file shortcut moment before!!! Hopefully I can track the modification history in Dropbox so I restored my file from 30 minutes earlier status. But I still lose all my changes in the last 30 minutes.

Just out of curiosity, I randomly do some changes to my file and hit the undo again. The same thing happened, but I did not hit save file this time XD…

I was trying to work out something before the deadline last night, so I did not do further research to this. Maybe later tonight I will try to reproduce this issue again to see if it is really an Atom issue.

I am not sure if this is because of Dropbox or the same file I open on my Win machine. But I cannot figure why it return to the status when I firstly on 7pm. I occasionally check my Win CTex so the status on my Win maybe like 10pm version or so.

Undo/redo broken

I’ve never seen Atom revert four hours worth of changes with a single press of Undo. Then again, I don’t edit files directly in Dropbox. It is possible perhaps that Dropbox constantly syncing the file would alter the Undo stack somehow?

@ProbablyCorey who would be the right person to take a look at this?


I’m not exactly sure why undo would cause Atom to hang, it is a pretty basic operation so I think it has something to do with Dropbox.

@ourlord, do you have autosave enabled? That may have also been a factor with this problem.


Do you mean auto save in Atom? I don’t think I turn on auto save either on Atom or the software I used to open that file on Windows. But the interesting thing is that Dropbox recorded each save I manually done, no any auto save recorded.

@ProbablyCorey I think this must be something with Dropbox. Never run into such situation if I was editing a local file.

@leedohm Yeah, maybe it’s really not a good habits to edit file in Dropbox…Fortunately only lost 30 minutes work…


I have the same problem with python files, normal text doesn’t happen.
Might it be that it’s some package interference with ‘undo’? - linter or language-python?
I am running Debian Testing.
Installed Atom with Ubuntu Trusty ppa from webupd8team.


So it seems like not a problem with Dropbox? Hmmm…
I have lang-python on my Atom. But at that time this issue happened I was editing LaTeX files.


I just experienced this.

I’m not using dropbox, just editing a js file directly on harddisk.

I hit the undo shortcut, the editor froze for a moment then it went back to a state from two hours ago - and the redo command won’t return it.

Luckily I did a git commit an hour ago, so not all is lost, but I still lost an hours work.

Is there any sort of log file that might hint at what happened?


@delameko Exactly the same scenario. It froze for a moment and everything is gone…


@delameko and @ourlord

Have you followed the suggestions in the Debugging document? Also, could you give the following information?

  • Which version of Atom are you using?
  • What OS and version are you running?
  • Have you been able reproduced the issue?

The theory was that what caused the issue was hitting Cmd+Alt+Z was causing Atom to revert to an older version of the file. So we added a confirmation dialog to that flow in atom/atom#3169 which was released in Atom v0.122.0.


I just checked the debugging document - I wish I’d thought to check the console before I shut Atom down.

  • I think it was 0.124.0, as I saw it was doing an update but I didn’t restart it, and I used it last week so it should have updated to the previous version then.
  • OSX 10.9.4
  • Unfortunately I couldn’t risk losing my work again yesterday, so I switched back to vim. I’ve got a personal project I’ll be working on tomorrow, I’ll try it out and see if it happens again.

I just tried cmd+alt+z and I got the prompt, so I doubt it was that. But then I see there was an issue with vim-mode, and I have that installed, so maybe its that. I’ll report back if it happens again.


The issue happened to me month ago and that device is not longer belongs to me now so I don’t know which version of Atom exactly is but I am pretty sure was the lastest version at that time. The operating system is OSX. I tried to reproduce the issue but seems not happen.