Make operations work with any (#2170)

waspc/data/Generator/templates/sdk/wasp/client/operations/rpc.ts

@@ -1,5 +1,6 @@
 import { type Route } from "wasp/client";
 import type {
+  IfAny,
   _Awaited,
   _ReturnType,
 } from "wasp/universal/types"
@@ -55,11 +56,11 @@ export type QueryMetadata = {
  */
 export type OperationRpcFor<BackendOperation extends GenericBackendOperation> =
   Parameters<BackendOperation> extends []
-    ? ClientOperation<void, _Awaited<_ReturnType<BackendOperation>>>
-    : ClientOperation<
-        Parameters<BackendOperation>[0],
-        _Awaited<_ReturnType<BackendOperation>>
-      >
+  ? ClientOperation<void, _Awaited<_ReturnType<BackendOperation>>>
+  : ClientOperation<
+    Parameters<BackendOperation>[0],
+    _Awaited<_ReturnType<BackendOperation>>
+  >
 
 // PRIVATE API (needed in SDK)
 /**
@@ -74,8 +75,21 @@ export type GenericBackendOperation = (args: never, context: any) => unknown
  */
 export type GenericOperationRpc = (args: never) => Promise<unknown>
 
+// NOTE: There's some duplication in the below types.
+// Read the discussion here to understand why before trying to remove it:
+// https://github.com/wasp-lang/wasp/pull/2170#discussion_r1671285049
+//
+// Read this to understand the type: https://github.com/wasp-lang/wasp/pull/2170#issue-2398830273
+type ClientOperation<Input, Output> =
+  IfAny<
+    Input,
+    (args?: any) => Promise<Output>,
+    ClientOperationWithNonAnyInput<Input, Output>
+  >
+
 // Read this to understand the type: https://github.com/wasp-lang/wasp/pull/1090#discussion_r1159732471
-type ClientOperation<Input, Output> = [Input] extends [never]
+type ClientOperationWithNonAnyInput<Input, Output> =
+  [Input] extends [never]
   ? (args?: unknown) => Promise<Output>
   : [Input] extends [void]
   ? () => Promise<Output>

waspc/data/Generator/templates/sdk/wasp/server/operations/wrappers.ts

@@ -1,5 +1,5 @@
 {{={= =}=}}
-import { _Awaited, _ReturnType } from '../../universal/types'
+import { IfAny, _Awaited, _ReturnType } from '../../universal/types'
 
 {=# isAuthEnabled =}
 import { type AuthUser } from 'wasp/auth'
@@ -160,6 +160,9 @@ function includesPayload<Input>(
 type AuthenticatedOperationArgsFor<Op extends GenericAuthenticatedOperationDefinition> =
   Parameters<AuthenticatedOperationFor<Op>>
 
+// NOTE: There's some duplication in the below types.
+// Read the discussion here to understand why before attempting to remove it:
+// https://github.com/wasp-lang/wasp/pull/2170#discussion_r1671285049
 /**
  * Constructs the type for an authenticated operation's server-side API.
  *
@@ -168,6 +171,14 @@ type AuthenticatedOperationArgsFor<Op extends GenericAuthenticatedOperationDefin
  * @template Output The type of the operation's return value.
  */
 type AuthenticatedOperation<Input, Output> =
+  IfAny<
+    Input,
+    (args: any, context: { user: AuthUser }) => Promise<Output>,
+    AuthenticatedOperationWithNonAnyInput<Input, Output>
+  >
+
+// Read this to understand the type: https://github.com/wasp-lang/wasp/pull/1090#discussion_r1159732471
+type AuthenticatedOperationWithNonAnyInput<Input, Output> =
   [Input] extends [never]
   ? (args: unknown, context: { user: AuthUser }) => Promise<Output>
   : [Input] extends [void]
@@ -187,6 +198,7 @@ type GenericAuthenticatedOperationDefinition = AuthenticatedOperationDefinition<
 >
 
 {=/ isAuthEnabled =}
+// Read this to understand the type: https://github.com/wasp-lang/wasp/pull/2170#issue-2398830273
 /**
  * Constructs the type for an unauthenticated operation's server-side API.
  *
@@ -195,13 +207,20 @@ type GenericAuthenticatedOperationDefinition = AuthenticatedOperationDefinition<
  * @template Output The type of the operation's return value.
  */
 type UnauthenticatedOperation<Input, Output> =
+  IfAny<
+    Input,
+    (args?: any) => Promise<Output>,
+    UnauthenticatedOperationWithNonAnyInput<Input, Output>
+  >
+
+// Read this to understand the type: https://github.com/wasp-lang/wasp/pull/1090#discussion_r1159732471
+type UnauthenticatedOperationWithNonAnyInput<Input, Output> =
   [Input] extends [never]
-  ? (args: unknown) => Promise<Output>
+  ? (args?: unknown) => Promise<Output>
   : [Input] extends [void]
   ? () => Promise<Output>
   : (args: Input) => Promise<Output>
 
-
 /**
  * The principal type for an unauthenticated operation's definition (i.e., all
  * unauthenticated operation definition types are a subtype of this type).

waspc/data/Generator/templates/sdk/wasp/universal/types.ts

@@ -27,9 +27,13 @@ export type _Awaited<T> = T extends Promise<infer V>
 // TODO: investigate how to properly specify the 'extends' constraint for function
 // type (i.e., any vs never and unknown) and stick with that. Take DX into
 // consideration.
-export type _ReturnType<T extends (...args: never[]) => unknown> = 
+export type _ReturnType<T extends (...args: never[]) => unknown> =
   T extends (...args: never[]) => infer R ? R : never
 
 
 // Returns elements of an array except the first one.
 export type Tail<T extends [unknown, ...unknown[]]> = T extends [unknown, ...infer R] ? R : never;
+
+
+// Source: https://stackoverflow.com/a/55541672
+export type IfAny<Value, Then, Else> = 0 extends (1 & Value) ? Then : Else;