[11.x] Improved Performance for Testing with In-Memory Databases (#47912)

* Transactional RefreshDatabase for in memory databases

This provides a significant performance increase for running
tests when using an in memory database.

* formatting

---------

Co-authored-by: Taylor Otwell <[email protected]>

Author: AJenbo

src/Illuminate/Foundation/Testing/RefreshDatabase.php

@@ -18,9 +18,11 @@ public function refreshDatabase()
     {
         $this->beforeRefreshingDatabase();
 
-        $this->usingInMemoryDatabase()
-                        ? $this->refreshInMemoryDatabase()
-                        : $this->refreshTestDatabase();
+        if ($this->usingInMemoryDatabase()) {
+            $this->restoreInMemoryDatabase();
+        }
+
+        $this->refreshTestDatabase();
 
         $this->afterRefreshingDatabase();
     }
@@ -38,28 +40,19 @@ protected function usingInMemoryDatabase()
     }
 
     /**
-     * Refresh the in-memory database.
+     * Restore the in-memory database between tests.
      *
      * @return void
      */
-    protected function refreshInMemoryDatabase()
+    protected function restoreInMemoryDatabase()
     {
-        $this->artisan('migrate', $this->migrateUsing());
-
-        $this->app[Kernel::class]->setArtisan(null);
-    }
+        $database = $this->app->make('db');
 
-    /**
-     * The parameters that should be used when running "migrate".
-     *
-     * @return array
-     */
-    protected function migrateUsing()
-    {
-        return [
-            '--seed' => $this->shouldSeed(),
-            '--seeder' => $this->seeder(),
-        ];
+        foreach ($this->connectionsToTransact() as $name) {
+            if (isset(RefreshDatabaseState::$inMemoryConnections[$name])) {
+                $database->connection($name)->setPdo(RefreshDatabaseState::$inMemoryConnections[$name]);
+            }
+        }
     }
 
     /**
@@ -91,6 +84,11 @@ public function beginDatabaseTransaction()
 
         foreach ($this->connectionsToTransact() as $name) {
             $connection = $database->connection($name);
+
+            if ($this->usingInMemoryDatabase()) {
+                RefreshDatabaseState::$inMemoryConnections[$name] ??= $connection->getPdo();
+            }
+
             $dispatcher = $connection->getEventDispatcher();
 
             $connection->unsetEventDispatcher();

src/Illuminate/Foundation/Testing/RefreshDatabaseState.php

@@ -4,6 +4,13 @@
 
 class RefreshDatabaseState
 {
+    /**
+     * The current SQLite in-memory database connections.
+     *
+     * @var array<string, \PDO>
+     */
+    public static $inMemoryConnections = [];
+
     /**
      * Indicates if the test database has been migrated.
      *