Fix regression: don't fatalError eagerly when calling deprecated unimplemented endpoints (#114)

* Added test for referencing unimplemented closures without placeholders.

* Fix test

---------

Co-authored-by: Stephen Celis <[email protected]>

Author: grigorye

Sources/XCTestDynamicOverlay/Internal/Deprecations.swift

@@ -277,7 +277,6 @@ public func unimplemented<Result>(
   }
 }
 
-@_disfavoredOverload
 @available(*, deprecated, renamed: "unimplemented(_:placeholder:)")
 public func unimplemented<each Argument, Result>(
   _ description: @autoclosure @escaping @Sendable () -> String = "",

Tests/XCTestDynamicOverlayTests/TestHelpers.swift

@@ -104,6 +104,12 @@ struct User { let id: UUID }
 @MainActor let f05: (String, Int, Double, [Int], User) -> Int = unimplemented(
   "f05", placeholder: 42)
 
+@available(*, deprecated)
+@MainActor let fm00: () -> Int = unimplemented("fm00")
+
+@available(*, deprecated)
+@MainActor let fm01: @MainActor () -> Int = unimplemented("fm01")
+
 @available(*, deprecated)
 private struct Autoclosing {
   init(

Tests/XCTestDynamicOverlayTests/UnimplementedTests.swift

@@ -2,6 +2,14 @@
   import XCTest
 
   final class UnimplementedTests: XCTestCase {
+
+    @available(*, deprecated)
+    @MainActor
+    func testXCTReferencingUnimplementedClosureDoesNotEvaluateIt() async throws {
+      _ = fm00
+      _ = fm01
+    }
+
     func testXCTFailShouldFail() async throws {
       _ = XCTExpectFailure {
         f00()