Detect size only change #95
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ScanNow() causes the file watch loop to run once, and ensures all events have been posted before returning. It allows the caller to "synchronize" with the pending watcher events, so is useful for batch updating after it is known file events have probably occurred.
On some file systems, multiple changes to the same file within the file system's mod time resolution would be missed. This issue can be ameliorated by triggering `Write` events if a size change is detected, even if no corresponding mod time change occurs. Changes to the file content without a change to the size or mod time will still go unnoticed.
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This PR builds on #94
Sometimes the watcher would not detect file changes if successive changes to a file happened very quickly, specifically within the min resolution that the underlying file system could represent for mod time stamps. In my case, I was testing on a file system which had 1 second mod time stamp resolution. If I edited a file twice in 1 second, then the second write event was lost.
This was principally visible in some unit tests where a series of quick modifications to files happened to occur, but it could happen in real situations also I guess, hence this fix.
The fix simply emits a
Writeevent if the mod time changes OR if the size changes.