Add additional typing to function definitions

+1 very sensible.

A couple of minor points:

We can remove the entire if statement checking if is_array() isn't true now.

public function search($query = '', array $params = array(), $method = 'GET') {
  if (!is_array($params)) {
    $params = array();
  }
   ...

This parameter should have a description to be 100% coding standards compliant. e.g.

   * @param DrupalApacheSolrService $solr
   *   The solr server resource to execute the search on.
   *

Great work, let's see if the test succeeds and we can start committing some of the patches you guys made :-)

DrupalApacheSolrService needs to be an interface not the concrete class - I'm confused as to why this doesn't break the tests using the Dummysolr class.

seems we don' have an interface at the moment, so we need to either define one, or not type hit DrupalApacheSolrService

Better would be to make the dummy (mock) class implement the interface independently. That would be a good basis for more unit testing in any case.

#18: 1708150-18.patch queued for re-testing.

Ugh, that's wrong we should not do that - it should just implement the interface, even if the functions are no-op for now.

Here's a new patch that move some helper functions out of the interface - either to private, or just let them be helpers that aren't part of the interface.

committed to 7.x

combined 6.x-3.x patch.

patch splitting out part to #1786450: apachesolr.interface.inc is not always loaded

That has to be applied at the same time

committed