Merge pull request #73635 from ktoso/wip-relax-macro-diagnostics

Author: ktoso

lib/Macros/Sources/SwiftMacros/DistributedResolvableMacro.swift

@@ -133,15 +133,6 @@ extension DistributedResolvableMacro {
     var isGenericStub = false
     var specificActorSystemRequirement: TypeSyntax?
 
-    if proto.genericWhereClause == nil {
-      throw DiagnosticsError(
-        syntax: node,
-        message: """
-                 Distributed protocol must declare actor system with SerializationRequirement, for example:
-                    protocol Greeter<ActorSystem>: DistributedActor where ActorSystem: DistributedActorSystem<any Codable>
-                 """, id: .invalidApplication)
-    }
-
     let accessModifiers = proto.accessControlModifiers
 
     for req in proto.genericWhereClause?.requirements ?? [] {

test/Distributed/Macros/distributed_macro_expansion_DistributedProtocol_errors.swift

@@ -26,7 +26,7 @@ distributed actor Caplin {
   typealias ActorSystem = FakeActorSystem
 }
 
-@Resolvable // expected-error{{Distributed protocol must declare actor system with SerializationRequirement}}
+@Resolvable // expected-note 3{{in expansion of macro 'Resolvable' on protocol 'Fail' here}}
 protocol Fail: DistributedActor {
   distributed func method() -> String
 }
@@ -35,7 +35,6 @@ protocol Fail: DistributedActor {
 public protocol SomeRoot: DistributedActor, Sendable
   where ActorSystem: DistributedActorSystem<any Codable> {
 
-  // TODO(distributed): we could diagnose this better?
   associatedtype AssociatedSomething: Sendable // expected-note{{protocol requires nested type 'AssociatedSomething'; add nested type 'AssociatedSomething' for conformance}}
   static var staticValue: String { get }
   var value: String { get }

test/Distributed/Macros/distributed_macro_expansion_DistributedProtocol_expansion_errors.swift

@@ -0,0 +1,25 @@
+// REQUIRES: swift_swift_parser, asserts
+//
+// UNSUPPORTED: back_deploy_concurrency
+// REQUIRES: concurrency
+// REQUIRES: distributed
+//
+// RUN: %empty-directory(%t)
+// RUN: %empty-directory(%t-scratch)
+
+// RUN: %target-swift-frontend-emit-module -emit-module-path %t/FakeDistributedActorSystems.swiftmodule -module-name FakeDistributedActorSystems -disable-availability-checking %S/../Inputs/FakeDistributedActorSystems.swift
+// RUN: not %target-swift-frontend -typecheck -disable-availability-checking -plugin-path %swift-plugin-dir -parse-as-library -I %t %S/../Inputs/FakeDistributedActorSystems.swift -dump-macro-expansions %s 2>&1 | %FileCheck %s
+
+import Distributed
+
+// These tests check the error output inside of a "bad" expansion;
+//
+// Since we cannot nicely diagnose these problems from the macro itself,
+// as it would need to inspect the type and its extensions and all involved
+// protocols., as at least
+
+// CHECK: macro expansion @Resolvable:1:[[COL:[0-9]+]]: error: distributed actor '$Fail' does not declare ActorSystem it can be used with
+@Resolvable
+protocol Fail: DistributedActor {
+  distributed func method() -> String
+}

test/Distributed/Macros/distributed_macro_expansion_DistributedProtocol_various_requirements.swift

@@ -140,3 +140,12 @@ public protocol GreeterMore: DistributedActor where ActorSystem == FakeActorSyst
 // CHECK:     }
 // CHECK:   }
 // CHECK: }
+
+
+// Should not fail:
+public protocol MyActorWithSystemRequirement: DistributedActor where ActorSystem == FakeActorSystem {}
+
+@Resolvable
+public protocol MyActorWithSystemRequirementImpl: MyActorWithSystemRequirement {
+  distributed func example()
+}