From a9804afe71fe5876963b3a6f5972a3e5d50dbdca Mon Sep 17 00:00:00 2001
From: Yusuke Wada <yusuke@kamawada.com>
Date: Thu, 28 Nov 2024 18:35:21 +0900
Subject: [PATCH] fix(zod-openapi): return `Response` if response is not text
 or JSON (#853)

* fix(zod-openapi): return `Response` if response is not text or JSON

Co-authored-by: sushichan044 <mail@sushichan.live>

* fixed tests and correct types

* add changeset

---------

Co-authored-by: sushichan044 <mail@sushichan.live>
---
 .changeset/fluffy-doors-carry.md            |  5 +++
 packages/zod-openapi/src/index.ts           | 37 ++++++++++++++++-----
 packages/zod-openapi/test/handler.test-d.ts | 24 +++++++++++++
 packages/zod-openapi/test/index.test-d.ts   |  2 +-
 packages/zod-openapi/test/index.test.ts     |  6 ++--
 5 files changed, 62 insertions(+), 12 deletions(-)
 create mode 100644 .changeset/fluffy-doors-carry.md

diff --git a/.changeset/fluffy-doors-carry.md b/.changeset/fluffy-doors-carry.md
new file mode 100644
index 00000000..234d0d6b
--- /dev/null
+++ b/.changeset/fluffy-doors-carry.md
@@ -0,0 +1,5 @@
+---
+'@hono/zod-openapi': patch
+---
+
+fix: return `Response` if response is not text or JSON
diff --git a/packages/zod-openapi/src/index.ts b/packages/zod-openapi/src/index.ts
index 0318ef81..62cb592f 100644
--- a/packages/zod-openapi/src/index.ts
+++ b/packages/zod-openapi/src/index.ts
@@ -26,7 +26,7 @@ import type {
   ValidationTargets,
 } from 'hono'
 import type { MergePath, MergeSchemaPath } from 'hono/types'
-import type { JSONParsed, RemoveBlankRecord } from 'hono/utils/types'
+import type { JSONParsed, JSONValue, RemoveBlankRecord, SimplifyDeepArray } from 'hono/utils/types'
 import type {
   ClientErrorStatusCode,
   InfoStatusCode,
@@ -69,6 +69,28 @@ type IsForm<T> = T extends string
     : never
   : never
 
+type ReturnJsonOrTextOrResponse<
+  ContentType,
+  Content,
+  Status extends keyof StatusCodeRangeDefinitions | StatusCode
+> = ContentType extends string
+  ? ContentType extends `application/${infer Start}json${infer _End}`
+    ? Start extends '' | `${string}+` | `vnd.${string}+`
+      ? TypedResponse<
+          SimplifyDeepArray<Content> extends JSONValue
+            ? JSONValue extends SimplifyDeepArray<Content>
+              ? never
+              : JSONParsed<Content>
+            : never,
+          ExtractStatusCode<Status>,
+          'json'
+        >
+      : never
+    : ContentType extends `text/plain${infer _Rest}`
+    ? TypedResponse<Content, ExtractStatusCode<Status>, 'text'>
+    : Response
+  : never
+
 type RequestPart<R extends RouteConfig, Part extends string> = Part extends keyof R['request']
   ? R['request'][Part]
   : {}
@@ -173,14 +195,13 @@ type ExtractStatusCode<T extends RouteConfigStatusCode> = T extends keyof Status
   ? StatusCodeRangeDefinitions[T]
   : T
 export type RouteConfigToTypedResponse<R extends RouteConfig> = {
-  [Status in keyof R['responses'] & RouteConfigStatusCode]: IsJson<
-    keyof R['responses'][Status]['content']
-  > extends never
+  [Status in keyof R['responses'] &
+    RouteConfigStatusCode]: undefined extends R['responses'][Status]['content']
     ? TypedResponse<{}, ExtractStatusCode<Status>, string>
-    : TypedResponse<
-        JSONParsed<ExtractContent<R['responses'][Status]['content']>>,
-        ExtractStatusCode<Status>,
-        'json' | 'text'
+    : ReturnJsonOrTextOrResponse<
+        keyof R['responses'][Status]['content'],
+        ExtractContent<R['responses'][Status]['content']>,
+        Status
       >
 }[keyof R['responses'] & RouteConfigStatusCode]
 
diff --git a/packages/zod-openapi/test/handler.test-d.ts b/packages/zod-openapi/test/handler.test-d.ts
index 9e1dea14..f8b56172 100644
--- a/packages/zod-openapi/test/handler.test-d.ts
+++ b/packages/zod-openapi/test/handler.test-d.ts
@@ -123,4 +123,28 @@ describe('supports async handler', () => {
       >
     >
   })
+
+  test('Route accepts a response other than the response from c.json() and c.text()', () => {
+    const route = createRoute({
+      method: 'get',
+      path: '/html',
+      responses: {
+        200: {
+          content: {
+            'text/html': {
+              schema: z.string(),
+            },
+          },
+          description: 'Return HTML',
+        },
+      },
+    })
+
+    const handler: RouteHandler<typeof route> = (c) => {
+      return c.html('<h1>Hello from html</h1>')
+    }
+
+    const hono = new OpenAPIHono()
+    hono.openapi(route, handler)
+  })
 })
diff --git a/packages/zod-openapi/test/index.test-d.ts b/packages/zod-openapi/test/index.test-d.ts
index fc24b654..e23ab9de 100644
--- a/packages/zod-openapi/test/index.test-d.ts
+++ b/packages/zod-openapi/test/index.test-d.ts
@@ -76,7 +76,7 @@ describe('Types', () => {
             id: number
             message: string
           }
-          outputFormat: 'json' | 'text'
+          outputFormat: 'json'
           status: 200
         }
       }
diff --git a/packages/zod-openapi/test/index.test.ts b/packages/zod-openapi/test/index.test.ts
index bbb1bf43..375c325e 100644
--- a/packages/zod-openapi/test/index.test.ts
+++ b/packages/zod-openapi/test/index.test.ts
@@ -1779,21 +1779,21 @@ describe('RouteConfigToTypedResponse', () => {
             age: number
           },
           200,
-          'json' | 'text'
+          'json'
         >
       | TypedResponse<
           {
             ok: boolean
           },
           400,
-          'json' | 'text'
+          'json'
         >
       | TypedResponse<
           {
             ok: boolean
           },
           ServerErrorStatusCode,
-          'json' | 'text'
+          'json'
         >
     type verify = Expect<Equal<Expected, Actual>>
   })