🔧 fix: handle error thrown as error

CHANGELOG.md

@@ -2,8 +2,11 @@
 Bug fix:
 - macro doesn't work with guard
 - [#981](https://github.com/elysiajs/elysia/issues/981) unable to deference schema, create default, and coerce value
+- [#966](https://github.com/elysiajs/elysia/issues/966) `error`'s value return as-if when thrown
 - [#964](https://github.com/elysiajs/elysia/issues/964) InvalidCookieSignature errors are not caught by onError
 - [#952](https://github.com/elysiajs/elysia/issues/952) onAfterResponse does not provide mapped response value unless aot is disabled
+- `mapResponse.response` is `{}` if no response schema is provided
+- Response doesn't reconcile when handler return `Response` is used with `mapResponse`
 
 # 1.2.6 - 25 Dec 2024
 Bug fix:

example/a.ts

@@ -1,13 +1,17 @@
-import { Elysia, t } from '../src'
+import { Elysia, t, error } from '../src'
 import { req } from '../test/utils'
 
-const app = new Elysia({ aot: false })
-	.onAfterResponse(({ response }) => {
-		console.log('Response:', response)
+const res = await new Elysia({
+	aot: false
+})
+	.get('/', () => 'Hi')
+	.onError(({ code }) => {
+		if (code === 'NOT_FOUND')
+			return new Response("I'm a teapot", {
+				status: 418
+			})
 	})
-	.get('/', async () => {
-		return { ok: true }
-	})
-	.listen(3000)
+	.handle(req('/not-found'))
 
-app.handle(req('/'))
+// console.log(await res.text())
+// console.log(res.status)

src/adapter/types.ts

@@ -129,6 +129,12 @@ export interface ElysiaAdapter {
 		inject?: Record<string, unknown>
 		mapResponseContext: string
 		validationError: string
+		/**
+		 * Handle thrown error which is instance of Error
+		 *
+		 * Despite its name of `unknownError`, it also handle named error like `NOT_FOUND`, `VALIDATION_ERROR`
+		 * It's named `unknownError` because it also catch unknown error
+		 */
 		unknownError: string
 	}
 	ws?(app: AnyElysia, path: string, handler: AnyWSLocalHook): unknown

src/adapter/web-standard/handler.ts

@@ -229,6 +229,17 @@ export const mergeResponseWithSetHeaders = (
 	response: Response,
 	set: Context['set']
 ) => {
+	if (
+		(response as Response).status !== set.status &&
+		set.status !== 200 &&
+		((response.status as number) <= 300 ||
+			(response.status as number) > 400)
+	)
+		response = new Response(response.body, {
+			headers: response.headers,
+			status: set.status as number
+		})
+
 	let isCookieSet = false
 
 	if (set.headers instanceof Headers)
@@ -246,8 +257,7 @@ export const mergeResponseWithSetHeaders = (
 		for (const key in set.headers)
 			(response as Response).headers.append(key, set.headers[key] as any)
 
-	if ((response as Response).status !== set.status)
-		set.status = (response as Response).status
+	return response
 }
 
 export const mapResponse = (
@@ -311,7 +321,10 @@ export const mapResponse = (
 				return Response.json(response, set as any)
 
 			case 'Response':
-				mergeResponseWithSetHeaders(response as Response, set)
+				response = mergeResponseWithSetHeaders(
+					response as Response,
+					set
+				)
 
 				if (
 					(response as Response).headers.get('transfer-encoding') ===
@@ -354,7 +367,10 @@ export const mapResponse = (
 
 			default:
 				if (response instanceof Response) {
-					mergeResponseWithSetHeaders(response as Response, set)
+					response = mergeResponseWithSetHeaders(
+						response as Response,
+						set
+					)
 
 					if (
 						(response as Response).headers.get(
@@ -496,7 +512,10 @@ export const mapEarlyResponse = (
 				return Response.json(response, set as any)
 
 			case 'Response':
-				mergeResponseWithSetHeaders(response as Response, set)
+				response = mergeResponseWithSetHeaders(
+					response as Response,
+					set
+				)
 
 				if (
 					(response as Response).headers.get('transfer-encoding') ===
@@ -540,7 +559,10 @@ export const mapEarlyResponse = (
 
 			default:
 				if (response instanceof Response) {
-					mergeResponseWithSetHeaders(response as Response, set)
+					response = mergeResponseWithSetHeaders(
+						response as Response,
+						set
+					)
 
 					if (
 						(response as Response).headers.get(

src/compose.ts

@@ -2279,13 +2279,13 @@ export const composeErrorHandler = (app: AnyElysia) => {
 	})
 
 	fnLiteral +=
-		`const set = context.set\n` +
+		`const set=context.set\n` +
 		`let _r\n` +
 		`if(!context.code)context.code=error.code??error[ERROR_CODE]\n` +
-		`if(!(context.error instanceof Error))context.error = error\n` +
+		`if(!(context.error instanceof Error))context.error=error\n` +
 		`if(error instanceof ElysiaCustomStatusResponse){` +
-		`error.status = error.code\n` +
-		`error.message = error.response` +
+		`set.status=error.status=error.code\n` +
+		`error.message=error.response` +
 		`}`
 
 	if (adapter.declare) fnLiteral += adapter.declare
@@ -2314,7 +2314,7 @@ export const composeErrorHandler = (app: AnyElysia) => {
 				`error.status=error.code\n` +
 				`error.message = error.response` +
 				`}` +
-				`if(set.status === 200) set.status = error.status\n`
+				`if(set.status===200||!set.status)set.status=error.status\n`
 
 			const mapResponseReporter = report('mapResponse', {
 				total: hooks.mapResponse.length,
@@ -2348,19 +2348,23 @@ export const composeErrorHandler = (app: AnyElysia) => {
 	fnLiteral +=
 		`if(error.constructor.name==="ValidationError"||error.constructor.name==="TransformDecodeError"){` +
 		`if(error.error)error=error.error\n` +
-		`set.status = error.status??422\n` +
+		`set.status=error.status??422\n` +
 		adapter.validationError +
-		`}else{` +
-		`if(error.code&&typeof error.status==="number"){` +
-		adapter.unknownError +
-		'}'
+		`}`
+
+	fnLiteral += `if(error instanceof Error){` + adapter.unknownError + `}`
 
 	const mapResponseReporter = report('mapResponse', {
 		total: hooks.mapResponse.length,
 		name: 'context'
 	})
 
+	fnLiteral +=
+		'\nif(!context.response)context.response=error.message??error\n'
+
 	if (hooks.mapResponse.length) {
+		fnLiteral += 'let mr\n'
+
 		for (let i = 0; i < hooks.mapResponse.length; i++) {
 			const mapResponse = hooks.mapResponse[i]
 
@@ -2369,18 +2373,18 @@ export const composeErrorHandler = (app: AnyElysia) => {
 			)
 
 			fnLiteral +=
-				`context.response=error\n` +
-				`error=${
-					isAsyncName(mapResponse) ? 'await ' : ''
-				}onMapResponse[${i}](context)\n`
+				`if(mr===undefined){` +
+				`mr=${isAsyncName(mapResponse) ? 'await ' : ''}onMapResponse[${i}](context)\n` +
+				`if(mr!==undefined)error=context.response=mr` +
+				'}'
 
 			endUnit()
 		}
 	}
 
 	mapResponseReporter.resolve()
 
-	fnLiteral += `\nreturn mapResponse(${saveResponse}error,set${adapter.mapResponseContext})}}`
+	fnLiteral += `\nreturn mapResponse(${saveResponse}error,set${adapter.mapResponseContext})}`
 
 	return Function(
 		'inject',

src/dynamic-handle.ts

@@ -30,8 +30,8 @@ const injectDefaultValues = (
 	typeChecker: TypeCheck<any>,
 	obj: Record<string, any>
 ) => {
-	// @ts-expect-error private
 	for (const [key, keySchema] of Object.entries(
+		// @ts-expect-error private
 		typeChecker.schema.properties
 	)) {
 		// @ts-expect-error private
@@ -459,8 +459,11 @@ export const createDynamicHandler = (app: AnyElysia) => {
 				error instanceof TransformDecodeError && error.error
 					? error.error
 					: error
-			if ((reportedError as ElysiaErrors).status)
-				set.status = (reportedError as ElysiaErrors).status
+
+			// ? Since error is reconciled in mergeResponseWithHeaders, this is not needed (if I'm not drunk)
+			// if ((reportedError as ElysiaErrors).status)
+			// 	set.status = (reportedError as ElysiaErrors).status
+
 			// @ts-expect-error private
 			return app.handleError(context, reportedError)
 		} finally {

src/types.ts

@@ -750,17 +750,29 @@ export type MapResponse<
 		resolve: {}
 	},
 	Path extends string | undefined = undefined
-> = Handler<
-	Omit<Route, 'response'> & {
-		response: {} extends Route['response'] ? unknown : Route['response']
-	},
-	Singleton & {
-		derive: {
-			response: Route['response']
-		}
-	},
-	Path
->
+> = (
+	context: Context<
+		Omit<Route, 'response'> & {},
+		Singleton & {
+			derive: {
+				response: {} extends Route['response']
+					? unknown
+					: Route['response']
+			}
+		},
+		Path
+	>
+) => MaybePromise<Response | void>
+
+// Handler<
+// 	Omit<Route, 'response'> & {},
+// 	Singleton & {
+// 		derive: {
+// 			response: {} extends Route['response'] ? unknown : Route['response']
+// 		}
+// 	},
+// 	Path
+// >
 
 export type VoidHandler<
 	in out Route extends RouteSchema = {},

test/core/handle-error.test.ts

@@ -70,9 +70,7 @@ describe('Handle Error', () => {
 	})
 
 	it('inject headers to error', async () => {
-		const app = new Elysia({
-			forceErrorEncapsulation: true
-		})
+		const app = new Elysia()
 			.onRequest(({ set }) => {
 				set.headers['Access-Control-Allow-Origin'] = '*'
 			})
@@ -248,4 +246,64 @@ describe('Handle Error', () => {
 		expect(response.status).toEqual(404)
 		expect(await response.text()).toEqual('foo')
 	})
+
+	it('map status error to response', async () => {
+		const value = { message: 'meow!' }
+
+		const response: Response = await new Elysia()
+			.get('/', () => 'Hello', {
+				beforeHandle({ error }) {
+					throw error("I'm a teapot", { message: 'meow!' })
+				}
+			})
+			// @ts-expect-error private property
+			.handleError(
+				{
+					request: new Request('http://localhost/'),
+					set: {
+						headers: {}
+					}
+				},
+				error(422, value) as any
+			)
+
+		expect(await response.json()).toEqual(value)
+		expect(response.headers.get('content-type')).toStartWith(
+			'application/json'
+		)
+		expect(response.status).toEqual(422)
+	})
+
+	it('map status error with custom mapResponse', async () => {
+		const value = { message: 'meow!' }
+
+		const response: Response = await new Elysia()
+			.mapResponse(({ response }) => {
+				if (typeof response === 'object')
+					return new Response('Don Quixote', {
+						headers: {
+							'content-type': 'text/plain'
+						}
+					})
+			})
+			.get('/', () => 'Hello', {
+				beforeHandle({ error }) {
+					throw error("I'm a teapot", { message: 'meow!' })
+				}
+			})
+			// @ts-expect-error private property
+			.handleError(
+				{
+					request: new Request('http://localhost/'),
+					set: {
+						headers: {}
+					}
+				},
+				error(422, value) as any
+			)
+
+		expect(await response.text()).toBe('Don Quixote')
+		expect(response.headers.get('content-type')).toStartWith('text/plain')
+		expect(response.status).toEqual(422)
+	})
 })