Try to remove duplication in operations

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

@@ -4,6 +4,7 @@ import type {
   _Awaited,
   _ReturnType,
 } from "wasp/universal/types"
+import { Expand } from "../../universal/types";
 
 // PRIVATE API (for SDK, should maybe be public, users define values of this
 // type).
@@ -77,16 +78,23 @@ export type GenericOperationRpc = (args: never) => Promise<unknown>
 
 // Read this to understand the type: https://github.com/wasp-lang/wasp/pull/2170#issue-2398830273
 type ClientOperation<Input, Output> =
-  IfAny<
+  Expand<IfAny<
     Input,
-    (args?: any) => Promise<Output>,
+    ClientOperationWithOptionalArgs<any, Output>,
     ClientOperationWithNonAnyInput<Input, Output>
-  >
+  >>
 
 // Read this to understand the type: https://github.com/wasp-lang/wasp/pull/1090#discussion_r1159732471
 type ClientOperationWithNonAnyInput<Input, Output> =
   [Input] extends [never]
-  ? (args?: unknown) => Promise<Output>
+  ? ClientOperationWithOptionalArgs<unknown, Output>
   : [Input] extends [void]
   ? () => Promise<Output>
-  : (args: Input) => Promise<Output>
+  : ClientOperationWithMandatoryArgs<Input, Output>
+
+type ClientOperationWithMandatoryArgs<Input, Output> =
+  (args: Input) => Promise<Output>
+
+type ClientOperationWithOptionalArgs<Input, Output> =
+  (args?: Input) => Promise<Output>
+

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

@@ -1,5 +1,10 @@
 {{={= =}=}}
-import { IfAny, _Awaited, _ReturnType } from '../../universal/types'
+import { 
+  IfAny,
+  _Awaited,
+  _ReturnType,
+  Expand 
+} from '../../universal/types'
 
 {=# isAuthEnabled =}
 import { type AuthUser } from 'wasp/auth'
@@ -168,18 +173,21 @@ type AuthenticatedOperationArgsFor<Op extends GenericAuthenticatedOperationDefin
  * @template Output The type of the operation's return value.
  */
 type AuthenticatedOperation<Input, Output> =
-  IfAny<
+  Expand<IfAny<
     Input,
-    (args: any, context: { user: AuthUser }) => Promise<Output>,
+    AuthenticatedOperationWithArgs<any, Output>,
     AuthenticatedOperationWithNonAnyInput<Input, Output>
-  >
+  >>
 
 type AuthenticatedOperationWithNonAnyInput<Input, Output> =
   [Input] extends [never]
-  ? (args: unknown, context: { user: AuthUser }) => Promise<Output>
+  ? AuthenticatedOperationWithArgs<unknown, Output>
   : [Input] extends [void]
   ? (context: { user: AuthUser }) => Promise<Output>
-  : (args: Input, context: { user: AuthUser }) => Promise<Output>
+  : AuthenticatedOperationWithArgs<Input, Output> 
+
+type AuthenticatedOperationWithArgs<Input, Output> = 
+  (args: Input, context: { user: AuthUser }) => Promise<Output>
 
 /**
  * The principal type for an authenticated operation's definition (i.e., all
@@ -203,19 +211,25 @@ type GenericAuthenticatedOperationDefinition = AuthenticatedOperationDefinition<
  * @template Output The type of the operation's return value.
  */
 type UnauthenticatedOperation<Input, Output> =
-  IfAny<
+  Expand<IfAny<
     Input,
-    (args: any) => Promise<Output>,
+    UnauthenticatedOperationWithOptionalArgs<any, 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>
+  ? UnauthenticatedOperationWithOptionalArgs<unknown, Output>
   : [Input] extends [void]
   ? () => Promise<Output>
-  : (args: Input) => Promise<Output>
+  : UnauthenticatedOperationWithMandatoryArgs<Input, Output>
+
+type UnauthenticatedOperationWithMandatoryArgs<Input, Output> = 
+  (args: Input) => Promise<Output>
+
+type UnauthenticatedOperationWithOptionalArgs<Input, Output> = 
+  (args?: Input) => Promise<Output>
 
 /**
  * The principal type for an unauthenticated operation's definition (i.e., all

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

@@ -1,14 +1,27 @@
-// This is a helper type used exclusively for DX purposes. It's a No-op for the
-// compiler, but expands the type's representatoin in IDEs (i.e., inlines all
-// type constructors) to make it more readable for the user.
-//
-// It expands this SO answer to functions: https://stackoverflow.com/a/57683652
+/**
+ * This is a helper type used exclusively for DX purposes. It's a No-op for the
+ * compiler, but expands the type's representatoin in IDEs (i.e., inlines all
+ * type constructors) to make it more readable for the user.
+ *
+ * It expands this SO answer to functions: https://stackoverflow.com/a/57683652
+ * Caveat: when used on functions that also have properties, the resulting type
+ * will lose those properties.
+ */
 export type Expand<T> = T extends (...args: infer A) => infer R
   ? (...args: A) => R
   : T extends infer O
   ? { [K in keyof O]: O[K] }
   : never
 
+export type ExpandCallSignature<T> = ExpandIfFunction<T> & ExpandIfObject<T>
+
+type ExpandIfObject<O> = O extends object ? { [K in keyof O]: O[K] } : O;
+
+type ExpandIfFunction<F> =
+  F extends (...args: infer Args) => infer Ret
+  ? (...args: Args) => Ret
+  : F
+
 // TypeScript's native Awaited type exhibits strange behavior in VS Code (see
 // https://github.com/wasp-lang/wasp/pull/1090#discussion_r1159687537 for
 // details). Until it's fixed, we're using our own type for this.

waspc/examples/todoApp/src/testTypes/operations/client.ts

@@ -17,6 +17,7 @@ import {
   getAnyAuth,
   getAnyNoAuth,
   getAnyToNumberSpecified,
+  getTask,
 } from 'wasp/client/operations'
 
 import {
@@ -66,4 +67,5 @@ type TestCases = [
   Expect<Equal<typeof getAnyAuth, QueryMetadata & ((args?: any) => Promise<any>)>>,
   Expect<Equal<typeof getAnyToNumberSpecified, QueryMetadata & ((args?: any) => Promise<number>)>>,
   Expect<Equal<typeof getMe, QueryMetadata & (() => Promise<AuthUser | null>)>>,
+  Expect<Equal<typeof getTask, QueryMetadata & ((args: Pick<Task, 'id'>) => Promise<Task>)>>,
 ]

waspc/examples/todoApp/src/testTypes/operations/server.ts

@@ -98,14 +98,27 @@ type TestCases = [
       (payload: boolean, ctx: { user: AuthUser }) => Promise<void>
     >
   >,
+  // I need a test for this but without auth
   Expect<
     Equal<
       typeof getAnything,
       (args: unknown, ctx: { user: AuthUser }) => Promise<Payload>
     >
   >,
-  Expect<Equal<typeof getTrueVoid, (ctx: { user: AuthUser }) => Promise<string>>>,
-  Expect<Equal<typeof getAnyNoAuth, (args: any) => Promise<any>>>,
-  Expect<Equal<typeof getAnyAuth, (args: any, ctx: { user: AuthUser }) => Promise<any>>>,
-  Expect<Equal<typeof getAnyToNumberSpecified, (args: any, ctx: { user: AuthUser }) => Promise<number>>>,
+  Expect<
+    Equal<typeof getTrueVoid, (ctx: { user: AuthUser }) => Promise<string>>
+  >,
+  Expect<Equal<typeof getAnyNoAuth, (args?: any) => Promise<any>>>,
+  Expect<
+    Equal<
+      typeof getAnyAuth,
+      (args: any, ctx: { user: AuthUser }) => Promise<any>
+    >
+  >,
+  Expect<
+    Equal<
+      typeof getAnyToNumberSpecified,
+      (args: any, ctx: { user: AuthUser }) => Promise<number>
+    >
+  >
 ]