From 6f9193db34ad3858fbfe2e857adfce4648b1aa8e Mon Sep 17 00:00:00 2001
From: "stainless-app[bot]"
 <142633134+stainless-app[bot]@users.noreply.github.com>
Date: Wed, 5 Feb 2025 18:03:43 +0000
Subject: [PATCH] chore: add UnionUnmarshaler for responses that are interfaces
 (#93)

---
 internal/apijson/registry.go | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/internal/apijson/registry.go b/internal/apijson/registry.go
index 2ea00ae..119cc5f 100644
--- a/internal/apijson/registry.go
+++ b/internal/apijson/registry.go
@@ -29,3 +29,13 @@ func RegisterUnion(typ reflect.Type, discriminator string, variants ...UnionVari
 		unionVariants[variant.Type] = typ
 	}
 }
+
+// Useful to wrap a union type to force it to use [apijson.UnmarshalJSON] since you cannot define an
+// UnmarshalJSON function on the interface itself.
+type UnionUnmarshaler[T any] struct {
+	Value T
+}
+
+func (c *UnionUnmarshaler[T]) UnmarshalJSON(buf []byte) error {
+	return UnmarshalRoot(buf, &c.Value)
+}