Broken NULL and NOT NULL operator on exposed image fid field

Thanks for taking the time to file this issue and for providing steps to reproduce and a views export as well. This is indeed a new regression introduced in 7.x-3.23. The last good revision is 0f6e47b1. The first bad revision is 50fe583e, so this regression has been introduced in #477984: CCK field is empty/not empty filter doesn't work when exposed.

Relevant part of the commit that introduced the regression:

      // Various ways to check for the absence of non-required input.
      if (empty($this->options['expose']['required'])) {
-        if (($this->operator == 'empty' || $this->operator == 'not empty') && $value === '') {
-          $value = ' ';
+        if ($this->operator == 'empty' || $this->operator == 'not empty') {
+          $value = is_array($value) ? $value['value'] : $value;
+          $this->operator = ($this->operator == 'empty' && empty($value)) || ($this->operator == 'not empty' && !empty($value)) ? 'not empty' : 'empty';
        }

Previously in the accept_exposed_input() method of the parent filter, the value was reset to a single space, if the operator was either empty or not empty and the value was empty. This code has been removed so the exposed input is rejected as invalid and the filter is not applied.

I guess the problem is, that the commit in question added a boolean filter to the exposed form, which allows users to select between "Yes", "No" and "Any" for either the "empty" or "not empty" operations. Unfortunately, the select is only rendered in the exposed_form() method of the parent filter, if the operator is initially configured to either "empty" or "not empty", but not if the operator is exposed and initially set to another operator like in your example view. Since the numeric filter doesn't provide any value for "empty" or "not empty" itself and the parent handler expects a non empty value (= user selected "Yes", apply operator) or an empty value (= user selected "No", apply opposite of operator) as exposed input and treats anything else as "user selected "Any", skip filter", it doesn't work anymore.

As soon as you set a value, it is not empty and thus treated as "user selected yes, apply operator" and the filter starts to work, so this explains your observation in #03.

Until this is fixed, you should be able to work around this using grouped filters as it seems that they are not affected.

Attached is a patch against 7.x-3.x-dev.

I fixed this by forcing a positive value in the accept_exposed_input() method of the filter, if the operator is exposed and the user selected either "empty" or "not empty", so that the parent method will accept the value. A better fix might be to change the exposed_form() method in the parent class to give the user a "Yes", "No", "Any" choice in this case as well, but that would probably require more testing and would also be a little bit more risky, so I didn't implement this for now.

To confirm that the fix works and doesn't break any existing functionality, I implemented tests for all operators when they are exposed. The rest of the exposed filters seem to be covered by the test relatively well. When writing the tests, I noticed that the "not between" operator is inclusive. I didn't expect that and I asked a colleague and she didn't expect it either, but this is probably implemented this way to mimic the inclusiveness of the BETWEEN operator in SQL, so I left it alone. Also, I would have expected the test data with the NULL value to be in the result sets for != value, not between value and value and value does not match not regular expression, but it seems that they are not. Again, I didn't change anything here either.

I think it would really make sense to check whether other filters extending the parent class are also affected by this, but I don't have time to do it right now. Maybe later, we'll see.

@pianomansam: Would you mind testing the patch in #5 to confirm it resolves the problem for you? Thanks.

I am experiencing this problem but my issue has nothing to do with 'images'.
I am filtering a CivICRM Group and a number of grouped filters. Two of the grouped filters contain a selection 'Is Empty (NULL)'. Selecting this entry in the exposed drop down filter returns all rows of data. The same happens with 'Is Not Empty (NOT NULL)', i.e. all rows are returned.
Regards
Martin Fuggle

I am experiencing this problem but my issue has nothing to do with 'images'.

This issue is in the numeric filter handler. If you are filtering on a field, that uses or extends this type of filter handler, you may be affected by this issue. Does the patch fix it for you?

If the patch doesn't fix your issue, it might be a similar, but ultimately different problem. In that case I suggest you create a new issue with steps to reproduce and attach an export of a view that demonstrates the problem. This might be your original view or, preferably, a reduced test case view. Reference this issue as a related issue and also post a comment about the new issue here, so that we can look into it. Thank you.

We've tested the patch from #5 for the problem raised in #11 and our initial findings is that also addresses this case.
> I am filtering a CivICRM Group and a number of grouped filters.

Thanks heaps for your work.

Just a further update - looks like this still has some problems we'll do some further testing to try and identify the cause.

Committed. Thank you.