Problem: Blocks based on views with dependencies on custom tables sometimes don't show up when we refreshed from the database dump, although things work if we update the database one revision at a time.
After far too much pain and suffering, I figured out that _views_get_default_views was caching the results. When it checked our newly-enabled modules for default views, it found some views whose dependencies hadn't gotten enabled yet, so it didn't cache those. The next time _views_get_default_views was called, it used the values it had stored in a static variable available only in that function.
_views_get_default_views did not provide a way to reset that static variable, so once it was called, the data was practically written in stone.
_views_get_tables is similarly evil. (ARGH!)
This might've been fixed in a Views update (and we're still using Drupal 5, in any case), but I'm not going to suggest updating the module this close to external acceptance testing.
So our options were:
- Make sure _block_rehash and similar functions never get called before the update function that enables the module. Problems: Not only do we need to untangle the order of update functions that get called and be hyper-aware of what other modules do, but we'll also need to change old update functions if we ever need to do this for another view in the future.
- Hack _views_get_default_views and _views_get_tables to accept an optional parameter that resets the static variable.
Was that really only one hour of my life? It felt so much longer.