Update ConditionalMetadata test case

Author: Kyle-Ye

Tests/OpenSwiftUICoreTests/Runtime/ConditionalMetadataTests.swift

@@ -20,6 +20,7 @@ extension TestProtocolDescriptor: ConditionalProtocolDescriptor {
 
 @Suite(.enabled(if: swiftToolchainSupported), .serialized)
 struct ConditionalMetadataTests {
+    struct EmptyP: TestProtocol {}
     struct P1: TestProtocol {}
     struct P2: TestProtocol {}
 
@@ -53,7 +54,7 @@ struct ConditionalMetadataTests {
     }
 
     @Test
-    func conditionalTypeDescriptorCaching() throws {
+    func conditionalTypeDescriptorCaching() {
         struct P3: TestProtocol {}
 
         let firstMetadata = Optional<P3>.makeConditionalMetadata(TestProtocolDescriptor.self)
@@ -62,4 +63,43 @@ struct ConditionalMetadataTests {
         let secondMetadata = Optional<P3>.makeConditionalMetadata(TestProtocolDescriptor.self)
         #expect(firstMetadata.ids != secondMetadata.ids)
     }
+
+    @Test
+    func childInfo() throws {
+        // optional
+        let optionalMetadata = Optional<P1>.makeConditionalMetadata(TestProtocolDescriptor.self)
+        let value: P1? = P1()
+        withUnsafePointer(to: value) { ptr in
+            let (type, id) = optionalMetadata.childInfo(ptr: ptr, emptyType: EmptyP.self)
+            #expect(type == P1.self)
+            #expect(id != nil)
+        }
+        let nilP: P1? = nil
+        withUnsafePointer(to: nilP) { ptr in
+            let (type, id) = optionalMetadata.childInfo(ptr: ptr, emptyType: EmptyP.self)
+            #expect(type == EmptyP.self)
+            #expect(id != nil)
+        }
+
+        // either
+        let eitherMetadata = ConditionalMetadata(ConditionalTypeDescriptor<TestProtocolDescriptor>(EitherType.self))
+        let trueValue = EitherType(__storage: .trueContent(P1()))
+        withUnsafePointer(to: trueValue) { ptr in
+            let (type, id) = eitherMetadata.childInfo(ptr: ptr, emptyType: EmptyP.self)
+            #expect(type == P1.self)
+            #expect(id != nil)
+        }
+        let falseValue = EitherType(__storage: .falseContent(P2()))
+        withUnsafePointer(to: falseValue) { ptr in
+            let (type, id) = eitherMetadata.childInfo(ptr: ptr, emptyType: EmptyP.self)
+            #expect(type == P2.self)
+            #expect(id != nil)
+        }
+        let otherValue = 0
+        withUnsafePointer(to: otherValue) { ptr in
+            let (type, id) = eitherMetadata.childInfo(ptr: ptr, emptyType: EmptyP.self)
+            #expect(type == P1.self)
+            #expect(id != nil)
+        }
+    }
 }