Proximity manual: SQLSTATE[42000]: Syntax error or access violation

[indigoxela]

This can easily happen when first setting the view up with (exposed) proximity search, but then also shows up front end.

The problem is that the manual proximity plugin can have empty values (in theory), but those aren't handled properly.

The current workaround is to either set the the input to be required (not always appropriate), or to set default values in the admin form.
But that's really only a workaround.

Full message:

Exception in (view name here): SQLSTATE[42000]: Syntax error or access violation: 1582 Incorrect parameter count in the call to native function 'RADIANS'

My suggestion is to make this fully work with optional values.

This problem is also known with Drupal 7, some attempts to patch that exist, but none of those actually fixes the problem, so let's come up with our own solution.

[indigoxela]

Here's a pull request: #57

Note that tests don't run in the workflow (see #58) - they pass locally.