macOS and linux: no way to correlate rename events

[christian-schulze]

File move operations on MacOS are reported by fswatch as pairs of Renamed events. The first event being the source and the second event being the destination.

Given the following scenario, the events are not reported in the correct order:

touch a 1; mv a b; mv 1 2; mv b c; mv 2 3

Actual output:

1. a -> CREATED RENAMED IS_FILE
2. 1 -> CREATED RENAMED IS_FILE
3. b -> RENAMED IS_FILE
4. c -> RENAMED IS_FILE
5. 2 -> RENAMED IS_FILE
6. 3 -> RENAMED IS_FILE

Given these results, there is no way to correlate event 3 with 1, and event 5 with 2.

If the Created and Renamed events were not merged into one event, then this might behave as expected. Is this something that fswatch is doing explicitly? Or is this what the MacOS API is reporting?

[emcrisostomo]

This is exactly what the macOS API is reporting, I'm afraid. There should be a way to correlate multiple rename events using inode identifiers (available since macOS 10.13 High Sierra IIRC), but I haven't looked into it yet.

[christian-schulze]

@emcrisostomo yes agreed, I've actually patched the fsevents node module to support this:
fsevents/fsevents#360

[emcrisostomo]

Thanks for the feedback @christian-schulze

[emcrisostomo]

I've update the issue since I've fixed this in the feature branch for both the fsevents_monitor and the inotify_monitor.

[emcrisostomo]

Merged into master.