Use IssueHandlingTrait to count issues

Sources/PropertyBased/IssueCounting.swift

@@ -12,13 +12,30 @@ func countIssues(isolation: isolated (any Actor)? = #isolation, suppress: Bool,
 {
     let found = Mutex(0)
 
-    // This is currently the only way to get a callback whenever an issue is found within a block.
+    #if swift(>=6.2)
+    nonisolated(unsafe) let closure = perform
+
+    let handler = IssueHandlingTrait.filterIssues { _ in
+        found.withLock { $0 += 1 }
+        return !suppress
+    }
+
+    try? await handler.provideScope(for: Test.current!, testCase: Test.Case.current) {
+        try await run(closure, in: isolation)
+    }
+    #else
     try? await withKnownIssue(isIntermittent: true, isolation: isolation) {
         try await perform()
     } matching: { _ in
         found.withLock { $0 += 1 }
         return suppress
     }
+    #endif
 
     return found.withLock { $0 }
 }
+
+@inlinable
+func run(_ closure: () async throws -> Void, in isolation: isolated (any Actor)?) async throws {
+    try await closure()
+}

Tests/PropertyBasedTests/ActorTests.swift

@@ -0,0 +1,40 @@
+//
+//  ActorTests.swift
+//  PropertyBased
+//
+//  Created by Lennard Sprong on 08/09/2025.
+//
+
+import Testing
+
+@testable import PropertyBased
+
+@globalActor actor OtherActor {
+    static let shared = OtherActor()
+
+    func doNothing() {}
+}
+
+@Suite(.shrinking) struct ActorTests {
+    @MainActor @Test func testOnMainActor() async {
+        let issues = await countIssues(suppress: true) {
+            await propertyCheck(input: Gen.int(in: 0...1000)) { i in
+                await OtherActor.shared.doNothing()
+                MainActor.assertIsolated("testOnMainActor failure")
+                #expect(i < 500)
+            }
+        }
+        #expect(issues > 0)
+    }
+
+    @OtherActor @Test func testOnOtherActor() async {
+        let issues = await countIssues(suppress: true) {
+            await propertyCheck(input: Gen.int(in: 0...1000)) { i in
+                await MainActor.run { /* do nothing */  }
+                OtherActor.assertIsolated("testOnOtherActor failure")
+                #expect(i < 500)
+            }
+        }
+        #expect(issues > 0)
+    }
+}