diff --git a/smithy-swift-codegen/src/test/kotlin/software/amazon/smithy/swift/codegen/protocolgeneratormocks/MockHTTPAWSJson11ProtocolGenerator.kt b/smithy-swift-codegen/src/test/kotlin/software/amazon/smithy/swift/codegen/protocolgeneratormocks/MockHTTPAWSJson11ProtocolGenerator.kt
index 7a0f0965d..ba806d5cc 100644
--- a/smithy-swift-codegen/src/test/kotlin/software/amazon/smithy/swift/codegen/protocolgeneratormocks/MockHTTPAWSJson11ProtocolGenerator.kt
+++ b/smithy-swift-codegen/src/test/kotlin/software/amazon/smithy/swift/codegen/protocolgeneratormocks/MockHTTPAWSJson11ProtocolGenerator.kt
@@ -71,6 +71,10 @@ class MockHTTPAWSJson11ProtocolGenerator() : HTTPBindingProtocolGenerator(MockAW
         // Intentionally empty
     }
 
+    override fun addUserAgentMiddleware(ctx: ProtocolGenerator.GenerationContext, operation: OperationShape) {
+        // Intentionally empty
+    }
+
     override fun getProtocolHttpBindingResolver(ctx: ProtocolGenerator.GenerationContext, defaultContentType: String):
         HttpBindingResolver = MockJsonHttpBindingResolver(ctx, defaultContentType)
 }
diff --git a/smithy-swift-codegen/src/test/kotlin/software/amazon/smithy/swift/codegen/protocolgeneratormocks/MockHTTPEC2QueryProtocolGenerator.kt b/smithy-swift-codegen/src/test/kotlin/software/amazon/smithy/swift/codegen/protocolgeneratormocks/MockHTTPEC2QueryProtocolGenerator.kt
index 9cc95f880..51c031110 100644
--- a/smithy-swift-codegen/src/test/kotlin/software/amazon/smithy/swift/codegen/protocolgeneratormocks/MockHTTPEC2QueryProtocolGenerator.kt
+++ b/smithy-swift-codegen/src/test/kotlin/software/amazon/smithy/swift/codegen/protocolgeneratormocks/MockHTTPEC2QueryProtocolGenerator.kt
@@ -48,6 +48,10 @@ class MockHTTPEC2QueryProtocolGenerator : HTTPBindingProtocolGenerator(MockEC2Qu
         // Intentionally empty
     }
 
+    override fun addUserAgentMiddleware(ctx: ProtocolGenerator.GenerationContext, operation: OperationShape) {
+        // Intentionally empty
+    }
+
     override fun getProtocolHttpBindingResolver(ctx: ProtocolGenerator.GenerationContext, defaultContentType: String):
         HttpBindingResolver = MockEC2QueryHttpBindingResolver(ctx, defaultContentType)
 
diff --git a/smithy-swift-codegen/src/test/kotlin/software/amazon/smithy/swift/codegen/protocolgeneratormocks/MockHTTPRestJsonProtocolGenerator.kt b/smithy-swift-codegen/src/test/kotlin/software/amazon/smithy/swift/codegen/protocolgeneratormocks/MockHTTPRestJsonProtocolGenerator.kt
index 271b08c93..bdae20c8b 100644
--- a/smithy-swift-codegen/src/test/kotlin/software/amazon/smithy/swift/codegen/protocolgeneratormocks/MockHTTPRestJsonProtocolGenerator.kt
+++ b/smithy-swift-codegen/src/test/kotlin/software/amazon/smithy/swift/codegen/protocolgeneratormocks/MockHTTPRestJsonProtocolGenerator.kt
@@ -28,6 +28,10 @@ class MockHTTPRestJsonProtocolGenerator : HTTPBindingProtocolGenerator(MockRestJ
         // Intentionally empty
     }
 
+    override fun addUserAgentMiddleware(ctx: ProtocolGenerator.GenerationContext, operation: OperationShape) {
+        // Intentionally empty
+    }
+
     override fun generateProtocolUnitTests(ctx: ProtocolGenerator.GenerationContext): Int {
         val requestTestBuilder = HttpProtocolUnitTestRequestGenerator.Builder()
         val responseTestBuilder = HttpProtocolUnitTestResponseGenerator.Builder()
diff --git a/smithy-swift-codegen/src/test/kotlin/software/amazon/smithy/swift/codegen/protocolgeneratormocks/MockHTTPRestXMLProtocolGenerator.kt b/smithy-swift-codegen/src/test/kotlin/software/amazon/smithy/swift/codegen/protocolgeneratormocks/MockHTTPRestXMLProtocolGenerator.kt
index 35e53c237..962eec1a3 100644
--- a/smithy-swift-codegen/src/test/kotlin/software/amazon/smithy/swift/codegen/protocolgeneratormocks/MockHTTPRestXMLProtocolGenerator.kt
+++ b/smithy-swift-codegen/src/test/kotlin/software/amazon/smithy/swift/codegen/protocolgeneratormocks/MockHTTPRestXMLProtocolGenerator.kt
@@ -29,6 +29,10 @@ class MockHTTPRestXMLProtocolGenerator : HTTPBindingProtocolGenerator(MockRestXM
         // Intentionally empty
     }
 
+    override fun addUserAgentMiddleware(ctx: ProtocolGenerator.GenerationContext, operation: OperationShape) {
+        // Intentionally empty
+    }
+
     override fun generateProtocolUnitTests(ctx: ProtocolGenerator.GenerationContext): Int {
         val requestTestBuilder = HttpProtocolUnitTestRequestGenerator.Builder()
         val responseTestBuilder = HttpProtocolUnitTestResponseGenerator.Builder()