perf(types): replace intersection with union to get better perf

src/hono-base.ts

@@ -212,7 +212,11 @@ class Hono<E extends Env = Env, S extends Schema = {}, BasePath extends string =
  >(
  path: SubPath,
  app: Hono<SubEnv, SubSchema, SubBasePath>
- ): Hono<E, MergeSchemaPath<SubSchema, MergePath<BasePath, SubPath>> & S, BasePath> {
+ ): Hono<
+ E,
+ ExcludeEmptyObject<MergeSchemaPath<SubSchema, MergePath<BasePath, SubPath>> | S>,
+ BasePath
+ > {
  const subApp = this.basePath(path)
  app.routes.map((r) => {
  let handler
@@ -519,5 +523,6 @@ class Hono<E extends Env = Env, S extends Schema = {}, BasePath extends string =
  })
  }
 }
+export type ExcludeEmptyObject<T> = T extends {} ? ({} extends T ? never : T) : T
 
 export { Hono as HonoBase }

src/types.ts

@@ -1817,24 +1817,21 @@ type ExtractParams<Path extends string> = string extends Path
 
 type FlattenIfIntersect<T> = T extends infer O ? { [K in keyof O]: O[K] } : never
 
-export type MergeSchemaPath<OrigSchema extends Schema, SubPath extends string> = Simplify<{
- [P in keyof OrigSchema as MergePath<SubPath, P & string>]: {
- [M in keyof OrigSchema[P]]: MergeEndpointParamsWithPath<OrigSchema[P][M], SubPath>
- }
-}>
-
-type MergeEndpointParamsWithPath<T, SubPath extends string> = T extends {
- input: infer Input
- output: infer Output
- outputFormat: infer OutputFormat
- status: infer Status
+export type MergeSchemaPath<OrigSchema extends Schema, SubPath extends string> = {
+ [P in keyof OrigSchema as MergePath<SubPath, P & string>]: [OrigSchema[P]] extends [
+ Record<string, Endpoint>
+ ]
+ ? { [M in keyof OrigSchema[P]]: MergeEndpointParamsWithPath<OrigSchema[P][M], SubPath> }
+ : never
 }
+
+type MergeEndpointParamsWithPath<T extends Endpoint, SubPath extends string> = T extends unknown
  ? {
- input: Input extends { param: infer _ }
+ input: T['input'] extends { param: infer _ }
  ? ExtractParams<SubPath> extends never
- ? Input
+ ? T['input']
  : FlattenIfIntersect<
- Input & {
+ T['input'] & {
  param: {
  // Maps extracted keys, stripping braces, to a string-typed record.
  [K in keyof ExtractParams<SubPath> as K extends `${infer Prefix}{${infer _}}`
@@ -1844,21 +1841,20 @@ type MergeEndpointParamsWithPath<T, SubPath extends string> = T extends {
  }
  >
  : RemoveBlankRecord<ExtractParams<SubPath>> extends never
- ? Input
- : Input & {
+ ? T['input']
+ : T['input'] & {
  // Maps extracted keys, stripping braces, to a string-typed record.
  param: {
  [K in keyof ExtractParams<SubPath> as K extends `${infer Prefix}{${infer _}}`
  ? Prefix
  : K]: string
  }
  }
- output: Output
- outputFormat: OutputFormat
- status: Status
+ output: T['output']
+ outputFormat: T['outputFormat']
+ status: T['status']
  }
  : never
-
 export type AddParam<I, P extends string> = ParamKeys<P> extends never
  ? I
  : I extends { param: infer _ }