To make for clean and readable tests, do your mocking in a base model that your Eloquent models extend.

BaseModel.php

<?php

class BaseModel extends Eloquent {
  public static function shouldReceive()
  {
    $repo = get_called_class() . 'RepositoryInterface';
    $mock = Mockery::mock($repo);

    App::instance($repo, $mock);

    return call_user_func_array(array($mock, 'shouldReceive'), func_get_args());
  }
}

ReadableLaravelTests.php

<?php

class PostsTest extends TestCase {
  public function testAllPosts()
  {
    // This will mock the PostRepository interface, update the instance
    // that will be injected into the controller (use DI), and stub the getAll method.
    // This way, the DB will never be hit.
    Post::shouldReceive('getAll')->andReturn('foo');

    // Call the route.
    $response = $this->call('GET', 'posts');

    // Make sure that the request was successful.
    $this->assertTrue($response->isOk());

    // also make sure that $posts is bound to the view
    $this->assertEquals('foo', $response->getOriginalContent()->posts);
  }
}

Would something along these lines do the trick without the "test logic in production code"?
https://gist.github.com/karptonite/4972230

It seems, as I think about it, that the part that ought to be simplified out is not the "shouldReceive" part, but the making of the mock, and binding it to the IoC. In fact, sometimes you might make and bind a mock without ever calling the shouldReceive method (if, for example, you want to prevent the class's constructor from running).

This could all easily be done within your base TestCase class -- but it lessens readability considerably.

I'm going to talk about it at my Laracon presentation this week, and ask for thoughts.

@karptonite How are you testing your EloquentFooRepository and mocking the injected Foo?

eg.:

<?php
class EloquentFooRepository implements FooRepositoryInterface {
  public function __construct(Foo $foo) {
    $this->foo = $foo;
  }

  public function all() {
    return $this->foo->all();
  }
}

// ...

class TestEloquentFooRepository extends TestCase {
  public function testAll() {
    $mock = m::mock('Foo')
      ->shouldReceive('all')->once()
      ->andReturn(array());

    App::instance('Foo', $mock);

    $repo = App::make('EloquentFooRepository');
    var_export($repo->all());
  }
}

Throws:

Starting test 'TestEloquentFooRepository::testAll'.
PHP Fatal error:  Using $this when not in object context in /Library/WebServer/Sites/jobs2/vendor/mockery/mockery/library/Mockery/Generator.php(129) : eval()'d code on line 119

I'm sure I'm missing something with the mock...

Calling it in the controller works and returns the correct DB data:

<?php

class FooController extends BaseController {
  public function __construct(FooRepositoryInterface $foo)
  {
    $this->foo = $foo;
  }

  public function index()
  {
    echo '<pre>';
    print_r($this->foo->all());
  }
}

// in routes:
App::bind('FooRepositoryInterface', 'EloquentFooRepository');

Edit: I'm now just using a sqlite db in memory instead of mocking it.

@danharper Just saw your question. My Repository tests also use sqlite in memory, rather than mocking the Foo. I get the same bug as you do when I try to mock Foo. I'm not certain, but I think that the problem is that all() is a static method.

@danharper in the framework tests, they extend the Eloquent class with a stub, to replace the newQuery method. IT is a bit convoluted, but it might work:
https://github.com/laravel/framework/blob/master/tests/Database/DatabaseEloquentModelTest.php

@karptonite Ah thanks, I'll give it a try! Only just noticed your reply, guess GitHub doesn't create notifications on mentions in Gists.

I had trouble using this snippet. I've found the problem to be namespaces. I thought I would share my modified code.

My repositories are in the Repositories namespace and models are in the Models namespace.

public static function shouldReceive($args)
{
    $calledClassParts = explode('\\', get_called_class());
    $calledClass = end($calledClassParts);

    $repo = 'Repositories\\' . $calledClass . 'RepositoryInterface';
    $mock = Mockery::mock($repo);

    App::instance($repo, $mock);

    return call_user_func_array([$mock, 'shouldReceive'], func_get_args());
}