Laravel/PHPUnit: Class not being mocked when tests are run - laravel

Question

I'm testing a class that calls a custom service and want to mock out the custom service.
The error is:
App\Jobs\CustomApiTest::getrandomInfo
Error: Call to a member function toArray() on null
This is because in getrandomInfo() there is a database call to fetch an ID and the test database is currently returning null because there is no entry, but the test should never even go that far because I am mocking out the getData function.
Machine Config:
Laravel 5.2
PHPUnit 4.8
I can not update my configuration.
MainClass.php
namespace App\Jobs;
use App\Services\CustomApi;
class MainClass
{
public function handle()
{
try {
$date = Carbon::yesterday();
$data = (new CustomApi($date))->getData();
} catch (Exception $e) {
Log::error("Error, {$e->getMessage()}");
}
}
}
MainClassTest.php
nameSpace App\Jobs;
use App\Services\CustomApi;
class MainClassTest extends \TestCase
{
/** #test */
public function handleGetsData()
{
$data = json_encode([
'randomInfo' => '',
'moreInfo' => ''
]);
$customApiMock = $this->getMockBuilder(App\Services\CustomApi::class)
->disableOriginalConstructor()
->setMethods(['getData'])
->getMock('CustomApi', ['getData']);
$customApiMock->expects($this->once())
->method('getData')
->will($this->returnValue($data));
$this->app->instance(App\Services\CustomApi::class, $customApiMock);
(new MainClass())->handle();
}
}
CustomApi Snippet
namespace App\Services;
class CustomApi
{
/**
* #var Carbon
*/
private $date;
public function __construct(Carbon $date)
{
$this->date = $date;
}
public function getData() : string
{
return json_encode([
'randomInfo' => $this->getrandomInfo(),
'moreInfo' => $this->getmoreInfo()
]);
}
}
I have tried many variations of the above code including:
Not using `disableOriginalConstructor()` when creating $externalApiMock.
Not providing parameters to `getMock()` when creating $externalApiMock.
Using `bind(App\Services\CustomApi::class, $customApiMock)` instead of instance(App\Services\CustomApi::class, $customApiMock) for the app.
Using willReturn($data)`` instead `will($this->returnValue($data))`.

Answer 1

I ended up creating a Service Provider and registering it in the app.php file. It seemed like the application was not saving the instance in the containers but works when it is bound to the service.