Date filter shows error in view exposed group filter with multiple select option.

**maybe** duplicate of 🐛 Views exposed group filter (with option allow multiple selections) generates notices when using date and date range fields Needs work ?

Made few changes on top of the MR. I will update the test cases as well.

Patch of #11

After applying the patch of #7 (which fixed the 'type' issue, well done.) I found this error:

Warning: Undefined array key "value" in Drupal\views\Plugin\views\filter\Date->acceptExposedInput() (line 153 of /var/www/html/web/core/modules/views/src/Plugin/views/filter/Date.php)

Looking into the code it seems that $operators[$operator]['values'] can be 1 without $this->value['value'] being set.

Perhaps we can add an isset test to the if statement in this block like:

if (!isset($this->value['value']) || $this->value['value'] == '') {
    return FALSE;
}

I'm suggesting this as a todo for you, as you already have the code and the existing patch available to you for tweaking. If it's preferable for me to try putting the combined patch together I can give it a shot. I hope this isn't too much of an imposition on your time.

This issue happened on my end; this is the view I tested: test_expose_date_filter.yml → or please see my screenshot →

I applied a patch and added a test case for this issue.

phthlaap → changed the visibility of the branch 3294700-warning-undefined-array-key-type to hidden.

Removing tests tag as coverage appears to be there.

Left some comments on the MR but proposed solution doesn't match the MR