test: add builder test

Author: calebdw

e2e/bug-11857/src/builders.php

@@ -0,0 +1,71 @@
+<?php
+
+namespace Bug11857;
+
+use function PHPStan\Testing\assertType;
+
+trait Filterable
+{
+	/**
+	 * @param array<string, mixed> $attributes
+	 * @return $this
+	 */
+	public function filter(array $attributes): static
+	{
+		// filter stuff
+		return $this;
+	}
+
+	/**
+	 * @param array<string, mixed> $attributes
+	 * @return $this
+	 */
+	public function filterUsingRequest(array $attributes): static
+	{
+		// request handling
+		return $this->filter($attributes);
+	}
+}
+
+/** @template TModel of Model */
+class Builder
+{
+	public function __construct(
+		/** @var TModel */
+		protected Model $model
+	) {
+	}
+
+}
+
+/**
+ * @template TModel of Model
+ * @extends Builder<TModel>
+ */
+class BaseBuilder extends Builder
+{
+	use Filterable;
+}
+
+/** @extends BaseBuilder<User> */
+class UserBuilder extends BaseBuilder {}
+
+/**
+ * @template TModel of Model
+ * @extends Builder<TModel>
+ */
+class PackageBuilder extends Builder {}
+
+// this extends a Builder coming from a package
+// so can't extend the BaseBuilder in our app
+/** @extends PackageBuilder<Comment> */
+final class CommentBuilder extends PackageBuilder
+{
+	use Filterable;
+}
+
+function test(UserBuilder $user, CommentBuilder $comment): void
+{
+	assertType(UserBuilder::class, $user->filterUsingRequest(['foo' => 'bar']));
+	assertType(CommentBuilder::class, $comment->filterUsingRequest(['foo' => 'bar']));
+}

e2e/bug-11857/src/test.php

@@ -66,5 +66,6 @@ function test(ChildPost $child): void
 {
 	assertType('Bug11857\BelongsTo<Bug11857\User, Bug11857\ChildPost>', $child->user());
 	// This demonstrates why `$this` is needed in non-final models
-	assertType('Bug11857\BelongsTo<Bug11857\User, Bug11857\Post>', $child->userSelf()); // should be: Bug11857\BelongsTo<Bug11857\User, Bug11857\ChildPost>
+	// Should be: Bug11857\BelongsTo<Bug11857\User, Bug11857\ChildPost>
+	assertType('Bug11857\BelongsTo<Bug11857\User, Bug11857\Post>', $child->userSelf());
 }