Touch files after moving

[nilbus]

Problem overview: A project I use on a docker container watches for changes to files. It ignores file added and moved_to events, only listening file modification FS events to trigger the desired behavior (which never happens with Mutagen). Mutegen's staging strategy is a good and correct one; I'm just looking into the possibility of a workaround.

This is a spike to see if I could get something working, not ready to merge.

I'm confident that Chtimes is running in my docker container, but unlike running touch locally, it's not triggering modifications.

I verified that the code in question is running by adding os.Create(filePath = ".synced") adjacent to the Chtimes call, and it does indeed create a .synced-suffixed file for each file that is modified.

I'll continue investigating, including confirming whether Chtimes returns any error, but please let me know if you have any ideas that might put me in the right direction.

[codecov-io]

Codecov Report

Merging #158 into master will increase coverage by 0.16%.
The diff coverage is 65.62%.

@@            Coverage Diff            @@
##           master    #158      +/-   ##
=========================================
+ Coverage   57.03%   57.2%   +0.16%     
=========================================
  Files         198     198              
  Lines       13055   13085      +30     
=========================================
+ Hits         7446    7485      +39     
+ Misses       4662    4655       -7     
+ Partials      947     945       -2

Impacted Files	Coverage Δ
pkg/filesystem/directory_posix.go	54.49% <60%> (+0.3%)	⬆️
pkg/filesystem/directory_windows.go	55.21% <60%> (+0.25%)	⬆️
pkg/synchronization/core/transition.go	66.47% <85.71%> (+0.33%)	⬆️
...ng/internal/third_party/winfsnotify/winfsnotify.go	63.12% <0%> (-0.8%)	⬇️
pkg/synchronization/controller.go	58.81% <0%> (-0.35%)	⬇️
...ing/internal/third_party/notify/watcher_inotify.go	62.78% <0%> (+1.34%)	⬆️
pkg/filesystem/watching/watch_recursive_windows.go	70.96% <0%> (+1.61%)	⬆️
pkg/synchronization/endpoint/local/endpoint.go	67.83% <0%> (+2.33%)	⬆️
pkg/agent/valve.go	94.73% <0%> (+10.52%)	⬆️

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[xenoscopic]

Hey, thanks for sending this and for the feedback regarding the watching behavior. I'm glad to hear that there's a simple solution that's workable. I'm not sure why you're seeing a behavioral difference between os.Chtimes and touch. My best guesses would be:

1. An error that's not being caught
2. A slightly different system call ordering or parameter set

The first should be relatively easy to pick up. The latter would probably involve attaching strace to the agent process running in the container and comparing that with the strace on touch.

I can have a look at this later this week.

[xenoscopic]

This is now tracked by #163.