diff --git a/Tests/RxCocoaTests/RXObjCRuntime+Testing.h b/Tests/RxCocoaTests/RXObjCRuntime+Testing.h
index 4dc0b13c..3a3f3197 100644
--- a/Tests/RxCocoaTests/RXObjCRuntime+Testing.h
+++ b/Tests/RxCocoaTests/RXObjCRuntime+Testing.h
@@ -163,7 +163,7 @@ DECLARE_OBSERVING_CLASS_PAIR_FOR_TEST(optimized_id)
 DECLARE_OBSERVING_CLASS_PAIR_FOR_TEST(optimized_closure)
 DECLARE_OBSERVING_CLASS_PAIR_FOR_TEST(optimized_int)
 DECLARE_OBSERVING_CLASS_PAIR_FOR_TEST(optimized_long)
-DECLARE_OBSERVING_CLASS_PAIR_FOR_TEST(optimized_BOOL)
+DECLARE_OBSERVING_CLASS_PAIR_FOR_TEST(optimized_char)
 DECLARE_OBSERVING_CLASS_PAIR_FOR_TEST(optimized_id_id)
 
 DECLARE_OBSERVING_CLASS_PAIR_FOR_TEST(dealloc)
diff --git a/Tests/RxCocoaTests/RXObjCRuntime+Testing.m b/Tests/RxCocoaTests/RXObjCRuntime+Testing.m
index b10f9210..601b58e8 100644
--- a/Tests/RxCocoaTests/RXObjCRuntime+Testing.m
+++ b/Tests/RxCocoaTests/RXObjCRuntime+Testing.m
@@ -547,7 +547,7 @@ IMPLEMENT_OBSERVING_CLASS_PAIR_FOR_TEST(optimized_id)
 IMPLEMENT_OBSERVING_CLASS_PAIR_FOR_TEST(optimized_closure)
 IMPLEMENT_OBSERVING_CLASS_PAIR_FOR_TEST(optimized_int)
 IMPLEMENT_OBSERVING_CLASS_PAIR_FOR_TEST(optimized_long)
-IMPLEMENT_OBSERVING_CLASS_PAIR_FOR_TEST(optimized_BOOL)
+IMPLEMENT_OBSERVING_CLASS_PAIR_FOR_TEST(optimized_char)
 IMPLEMENT_OBSERVING_CLASS_PAIR_FOR_TEST(optimized_id_id)
 
 _IMPLEMENT_OBSERVING_CLASS_PAIR_FOR_TEST(dealloc,,)
diff --git a/Tests/RxCocoaTests/SentMessageTest.swift b/Tests/RxCocoaTests/SentMessageTest.swift
index 1a0fb9f3..edbeccf7 100644
--- a/Tests/RxCocoaTests/SentMessageTest.swift
+++ b/Tests/RxCocoaTests/SentMessageTest.swift
@@ -337,13 +337,13 @@ extension SentMessageTest {
         }
     }
 
-    func testBaseClass_subClass_dont_interact_for_optimized_version_BOOL() {
+    func testBaseClass_subClass_dont_interact_for_optimized_version_char() {
         _baseClass_subClass_dont_interact_for_optimized_version(
-            SentMessageTestBase_optimized_BOOL.self,
-            SentMessageTest_optimized_BOOL.self,
-            "voidJustCalledToSayBool:") { target in
-            target.voidJustCalledToSayBool(true)
-            return [[[NSNumber(bool: true)]]]
+            SentMessageTestBase_optimized_char.self,
+            SentMessageTest_optimized_char.self,
+            "voidJustCalledToSayChar:") { target in
+            target.voidJustCalledToSayChar(3)
+            return [[[NSNumber(char: 3)]]]
         }
     }
 
@@ -824,11 +824,10 @@ extension SentMessageTest {
         _testMessageRecordedAndAllCallsAreMade("voidJustCalledToSayUnsignedLong:", sendMessage: { x in x.voidJustCalledToSayUnsignedLong(11); return 11 }, expectedResult: 11)
         _testMessageRecordedAndAllCallsAreMade("voidJustCalledToSayFloat:", sendMessage: { x in x.voidJustCalledToSayFloat(13); return 13 }, expectedResult: 13)
         _testMessageRecordedAndAllCallsAreMade("voidJustCalledToSayDouble:", sendMessage: { x in x.voidJustCalledToSayDouble(13); return 13 }, expectedResult: 13)
-        _testMessageRecordedAndAllCallsAreMade("voidJustCalledToSayBool:", sendMessage: { x in x.voidJustCalledToSayBool(true); return true }, expectedResult: true)
 
         let endRuntimeState = RxObjCRuntimeState()
 
-        endRuntimeState.assertAfterThisMoment(middleRuntimeState, changed: RxObjCRuntimeChange.changes(methodsSwizzled: 13))
+        endRuntimeState.assertAfterThisMoment(middleRuntimeState, changed: RxObjCRuntimeChange.changes(methodsSwizzled: 12))
 
     }