Allow classes to be passed into Injector::inst()->load()

src/Core/Injector/InjectionCreator.php

@@ -9,11 +9,17 @@ class InjectionCreator implements Factory
 {
     public function create($class, array $params = [])
     {
-        if (!class_exists($class ?? '')) {
+        // Allow anonymous classes or other classes to pass without ReflectionClass
+        if (is_object($class)) {
+            return $class;
+        } 
+        elseif (!class_exists($class ?? '')) {
             throw new InjectorNotFoundException("Class {$class} does not exist");
         }
+
         // Ensure there are no string keys as they cannot be unpacked with the `...` operator
         $values = array_values($params ?? []);
+
         return new $class(...$values);
     }
 }

tests/php/Core/Injector/InjectorTest.php

@@ -22,11 +22,10 @@
 use SilverStripe\Core\Tests\Injector\InjectorTest\OriginalRequirementsBackend;
 use SilverStripe\Core\Tests\Injector\InjectorTest\OtherTestObject;
 use SilverStripe\Core\Tests\Injector\InjectorTest\TestObject;
+use SilverStripe\Core\Tests\Injector\InjectorTest\TestObjectTwo;
 use SilverStripe\Core\Tests\Injector\InjectorTest\TestSetterInjections;
 use SilverStripe\Core\Tests\Injector\InjectorTest\TestStaticInjections;
 use SilverStripe\Dev\SapphireTest;
-use SilverStripe\Dev\TestOnly;
-use stdClass;
 
 define('TEST_SERVICES', __DIR__ . '/AopProxyServiceTest');
 
@@ -1065,4 +1064,27 @@ public function testNest()
         Injector::unnest();
         $this->nestingLevel--;
     }
+
+    public function testAnonymousClass()
+    {
+        // load a mock & method override via Injector
+        Injector::inst()->load([
+            TestObject::class => [
+                'class' => new class {
+                    public function foo(): string
+                    {
+                        return TestObject::TEST_BAZ;
+                    }
+                },
+            ],
+        ]);
+
+        $myObject = new TestObjectTwo();
+
+        $this->assertEquals(
+            TestObject::TEST_BAZ,
+            $myObject->fooViaTestObject(),
+            'Function return does not match what was mocked above'
+        );
+    }
 }

tests/php/Core/Injector/InjectorTest/TestObject.php

@@ -2,10 +2,15 @@
 
 namespace SilverStripe\Core\Tests\Injector\InjectorTest;
 
+use SilverStripe\Core\Injector\Injectable;
 use SilverStripe\Dev\TestOnly;
 
 class TestObject implements TestOnly
 {
+    use Injectable;
+
+    const TEST_BAR = 'bar';
+    const TEST_BAZ = 'baz';
 
     public $sampleService;
 
@@ -30,4 +35,9 @@ protected function protectedMethod()
     {
         $this->methodCalls[] = 'protectedMethod called';
     }
+
+    public function foo(): string
+    {
+        return self::TEST_BAR;
+    }
 }

tests/php/Core/Injector/InjectorTest/TestObjectTwo.php

@@ -0,0 +1,16 @@
+<?php
+
+namespace SilverStripe\Core\Tests\Injector\InjectorTest;
+
+use SilverStripe\Core\Injector\Injectable;
+use SilverStripe\Dev\TestOnly;
+
+class TestObjectTwo implements TestOnly
+{
+    public function fooViaTestObject(): string
+    {
+        $obj1 = TestObject::create();
+
+        return $obj1->foo();
+    }
+}