Triggering report generation after package update

report_on_update.py

import sublime

watcher = None

class SettingsWatcher():
    def __init__(self):
        self.removed = set()
        self.settings = sublime.load_settings("Preferences.sublime-settings")
        self.cached_ignored = set(self.settings.get("ignored_packages", []))

        self.settings.add_on_change("_oa_sw", lambda: self.settings_changed())

    def unregister(self):
        self.settings.clear_on_change("_oa_sw")

    def run_report(self, removed_set):
        # If the set we got is not the same as the one we currently have, the
        # list changed since the job was scheduled, so do nothing here. If the
        # new list still shows that something was removed from the list, a new
        # job was scheduled. Otherwise we assume that the ignored package was
        # added back.
        if removed_set != self.removed:
            return

        # Empty the list of removed packages that triggered us.
        self.removed = set()
        print("Generating expired override report")

    def settings_changed(self):
        # Get the new ignored list; leave if it's the same
        new_list = set(self.settings.get("ignored_packages", []))
        if new_list == self.cached_ignored:
            return

        # Determine the packages added to and removed from the ignored packages
        # setting since the last time we were loaded, then update our cache.
        removed = self.cached_ignored - new_list
        added = new_list - self.cached_ignored
        self.cached_ignored = new_list

        # Add the newly removed packages to our list of removed packages.
        self.removed |= removed

        # Remove from the list of removed packages any that might have been
        # added back in.
        self.removed -= added

        # If there are any packages listed as removed, trigger a report. We pad
        # the time a bit so that we can ignore this report if the list is still
        # in flux.
        if len(self.removed) != 0:
            # Command takes a copy of the set of removed packages as we know it
            # right now; this lets the command know if it should do nothing if
            # the list changed before the timeout expires.
            current = set(self.removed)
            sublime.set_timeout(lambda: self.run_report(current), 60 * 1000)


def plugin_loaded():
    global watcher
    watcher = SettingsWatcher()

def plugin_unloaded():
    global watcher
    watcher.unregister()

As a note, On Windows/OSX Package names are not case sensitive because the file system isn't, so adding "VINTAGE" to the list of ignored packages is the same as adding "Vintage". For this to be more bullet proof, the package sets used here need to be case insensitive, such as https://github.com/OdatNurd/OverrideAudit/blob/master/lib/packages.py#L61.