collectstatic does not take into account modified dependencies

[motiejus]

Assume the following:

1. styles.css includes other.css
2. ./manage.py collectstatic
3. modify other.css
4. ./manage.py collectstatic

Expected outcome:
styles.css is changed (and hence a new file is created in STATIC_ROOT) to reflect new other.css

Actual outcome:
styles.css remains unchanged, and it wrongly includes the old other.css.

Test case is far from perfect, because it changes global state (style.css and other.css). I tried to copy files I am modifying to a separate temporary directory, but for some reason it didn't work out. See the temp_staticfiles_dirs decorator in the patch, might be that only a bit is missing (clearing cache or something).

[motiejus]

There are two bugs in this ticket. One is line 440 in my patch. Once that one is fixed, we can concentrate on lines 452-474.

[Jannis Leidel]

I can't reproduce this, and I suspect it's a misconfiguration, where an item of the STATICFILES_DIRS setting is inside the STATIC_ROOT directory or something similar.

Your patch doesn't seem to use the decorator you've wrote, please provide more information to understand the issue.