Make createLocalViewFactory compatible with Laravel 8 (#1026)

* Make createLocalViewFactory compatible with Laravel 8

Fixes https://github.com/barryvdh/laravel-ide-helper/issues/1024

* tests: move up mockFilesystem so it get be re-used in other tests

Note: removed `$this->mockOutput = '';` as it was a no-op, that property
doesn't exist (it was probably a typo, but I guess we don't need it
anyway)

* tests: show basic features for ide-helper:meta working

tests/TestCase.php

@@ -5,6 +5,8 @@ declare(strict_types=1);
 namespace Barryvdh\LaravelIdeHelper\Tests;
 
 use Illuminate\Console\Command;
+use Illuminate\Filesystem\Filesystem;
+use Mockery;
 use Orchestra\Testbench\TestCase as BaseTestCase;
 use Spatie\Snapshots\MatchesSnapshots;
 use Symfony\Component\Console\Tester\CommandTester;
@@ -13,6 +15,8 @@ abstract class TestCase extends BaseTestCase
 {
     use MatchesSnapshots;
 
+    protected $mockFilesystemOutput;
+
     /**
      * The `CommandTester` is directly returned, use methods like
      * `->getDisplay()` or `->getStatusCode()` on it.
@@ -50,4 +54,30 @@ abstract class TestCase extends BaseTestCase
     {
         $this->assertMatchesSnapshot($actualContent, new SnapshotTxtDriver());
     }
+
+    protected function mockFilesystem()
+    {
+        $mockFilesystem = Mockery::mock(Filesystem::class);
+
+        $mockFilesystem
+            ->shouldReceive('get')
+            ->andReturnUsing(function ($file) {
+                return file_get_contents($file);
+            });
+
+        $mockFilesystem
+            ->shouldReceive('put')
+            ->with(
+                Mockery::any(),
+                Mockery::any()
+            )
+            ->andReturnUsing(function ($path, $contents) {
+                $this->mockFilesystemOutput .= $contents;
+
+                return strlen($contents);
+            });
+
+        $this->instance(Filesystem::class, $mockFilesystem);
+        $this->instance('files', $mockFilesystem);
+    }
 }