Document what is being tested a little better so it isn't just a wall of code

app/Services/Deployment/FindViableNodesService.php

@@ -97,8 +97,8 @@ class FindViableNodesService
         }
 
         $results = $query->groupBy('nodes.id')
-            ->havingRaw('(IFNULL(SUM(servers.memory), 0) + ?) < (nodes.memory * (1 + (nodes.memory_overallocate / 100)))', [ $this->memory ])
+            ->havingRaw('(IFNULL(SUM(servers.memory), 0) + ?) <= (nodes.memory * (1 + (nodes.memory_overallocate / 100)))', [ $this->memory ])
-            ->havingRaw('(IFNULL(SUM(servers.disk), 0) + ?) < (nodes.disk * (1 + (nodes.disk_overallocate / 100)))', [ $this->disk ])
+            ->havingRaw('(IFNULL(SUM(servers.disk), 0) + ?) <= (nodes.disk * (1 + (nodes.disk_overallocate / 100)))', [ $this->disk ])
             ->get()
             ->toBase();
 

tests/Integration/Services/Deployment/FindViableNodesServiceTest.php

@@ -4,7 +4,9 @@ namespace Pterodactyl\Tests\Integration\Services\Deployment;
 
 use Pterodactyl\Models\Node;
 use InvalidArgumentException;
+use Pterodactyl\Models\Server;
 use Pterodactyl\Models\Location;
+use Pterodactyl\Models\Database;
 use Illuminate\Support\Collection;
 use Pterodactyl\Tests\Integration\IntegrationTestCase;
 use Pterodactyl\Services\Deployment\FindViableNodesService;
@@ -12,6 +14,15 @@ use Pterodactyl\Exceptions\Service\Deployment\NoViableNodeException;
 
 class FindViableNodesServiceTest extends IntegrationTestCase
 {
+    public function setUp(): void
+    {
+        parent::setUp();
+
+        Database::query()->delete();
+        Server::query()->delete();
+        Node::query()->delete();
+    }
+
     public function testExceptionIsThrownIfNoDiskSpaceHasBeenSet()
     {
         $this->expectException(InvalidArgumentException::class);
@@ -35,10 +46,11 @@ class FindViableNodesServiceTest extends IntegrationTestCase
 
         /** @var \Pterodactyl\Models\Node[] $nodes */
         $nodes = [
-            // This node should never be returned.
+            // This node should never be returned once we've completed the initial test which
+            // runs without a location filter.
             factory(Node::class)->create([
                 'location_id' => $locations[0]->id,
-                'memory' => 10240,
+                'memory' => 2048,
                 'disk' => 1024 * 100,
             ]),
             factory(Node::class)->create([
@@ -55,40 +67,72 @@ class FindViableNodesServiceTest extends IntegrationTestCase
             ]),
         ];
 
+        // Expect that all of the nodes are returned as we're under all of their limits
+        // and there is no location filter being provided.
+        $response = $this->getService()->setDisk(512)->setMemory(512)->handle();
+        $this->assertInstanceOf(Collection::class, $response);
+        $this->assertCount(3, $response);
+        $this->assertInstanceOf(Node::class, $response[0]);
+
+        // Expect that only the last node is returned because it is the only one with enough
+        // memory available to this instance.
+        $response = $this->getService()->setDisk(512)->setMemory(2049)->handle();
+        $this->assertInstanceOf(Collection::class, $response);
+        $this->assertCount(1, $response);
+        $this->assertSame($nodes[2]->id, $response[0]->id);
+
+        // Helper, I am lazy.
         $base = function () use ($locations) {
             return $this->getService()->setLocations([ $locations[1]->id ])->setDisk(512);
         };
 
+        // Expect that we can create this server on either node since the disk and memory
+        // limits are below the allowed amount.
         $response = $base()->setMemory(512)->handle();
-        $this->assertInstanceOf(Collection::class, $response);
+        $this->assertCount(2, $response);
-        $this->assertFalse($response->isEmpty());
-        $this->assertSame(2, $response->count());
         $this->assertSame(2, $response->where('location_id', $locations[1]->id)->count());
 
+        // Expect that we can only create this server on the second node since the memory
+        // allocated is over the amount of memory available to the first node.
         $response = $base()->setMemory(2048)->handle();
-        $this->assertSame(1, $response->count());
+        $this->assertCount(1, $response);
         $this->assertSame($nodes[2]->id, $response[0]->id);
 
+        // Expect that we can only create this server on the second node since the disk
+        // allocated is over the limit assigned to the first node (even with the overallocate).
         $response = $base()->setDisk(20480)->setMemory(256)->handle();
-        $this->assertSame(1, $response->count());
+        $this->assertCount(1, $response);
         $this->assertSame($nodes[2]->id, $response[0]->id);
 
-        $response = $base()->setDisk(11263)->setMemory(256)->handle();
+        // Expect that we could create the server on either node since the disk allocated is
-        $this->assertSame(2, $response->count());
+        // right at the limit for Node 1 when the overallocate value is included in the calc.
+        $response = $base()->setDisk(11264)->setMemory(256)->handle();
+        $this->assertCount(2, $response);
 
+        // Create two servers on the first node so that the disk space used is equal to the
+        // base amount available to the node (without overallocation included).
         $servers = Collection::make([
             $this->createServerModel(['node_id' => $nodes[1]->id, 'disk' => 5120]),
             $this->createServerModel(['node_id' => $nodes[1]->id, 'disk' => 5120]),
         ]);
 
+        // Expect that we cannot create a server with a 1GB disk on the first node since there
+        // is not enough space (even with the overallocate) available to the node.
         $response = $base()->setDisk(1024)->setMemory(256)->handle();
-        $this->assertSame(1, $response->count());
+        $this->assertCount(1, $response);
         $this->assertSame($nodes[2]->id, $response[0]->id);
+
+        // Cleanup servers since we need to test some other stuff with memory here.
         $servers->each->delete();
 
+        // Expect that no viable node can be found when the memory limit for the given instance
+        // is greater than either node can support, even with the overallocation limits taken
+        // into account.
         $this->expectException(NoViableNodeException::class);
         $base()->setMemory(10000)->handle();
 
+        // Create four servers so that the memory used for the second node is equal to the total
+        // limit for that node (pre-overallocate calculation).
         Collection::make([
             $this->createServerModel(['node_id' => $nodes[2]->id, 'memory' => 1024]),
             $this->createServerModel(['node_id' => $nodes[2]->id, 'memory' => 1024]),
@@ -96,12 +140,16 @@ class FindViableNodesServiceTest extends IntegrationTestCase
             $this->createServerModel(['node_id' => $nodes[2]->id, 'memory' => 1024]),
         ]);
 
+        // Expect that either node can support this server when we account for the overallocate
+        // value of the second node.
         $response = $base()->setMemory(500)->handle();
-        $this->assertSame(2, $response->count());
+        $this->assertCount(2, $response);
         $this->assertSame(2, $response->where('location_id', $locations[1]->id)->count());
 
-        $response = $base()->setMemory(512)->handle();
+        // Expect that only the first node can support this server when we go over the remaining
-        $this->assertSame(1, $response->count());
+        // memory for the second nodes overallocate calculation.
+        $response = $base()->setMemory(640)->handle();
+        $this->assertCount(1, $response);
         $this->assertSame($nodes[1]->id, $response[0]->id);
     }