diff --git a/src/error.rs b/src/error.rs
index 2231473f2..fc0f9fdf3 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -142,3 +142,34 @@ impl ResponseError for ReadlinesError {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_urlencoded_error() {
+        let resp: HttpResponse = UrlencodedError::Overflow.error_response();
+        assert_eq!(resp.status(), StatusCode::PAYLOAD_TOO_LARGE);
+        let resp: HttpResponse = UrlencodedError::UnknownLength.error_response();
+        assert_eq!(resp.status(), StatusCode::LENGTH_REQUIRED);
+        let resp: HttpResponse = UrlencodedError::ContentType.error_response();
+        assert_eq!(resp.status(), StatusCode::BAD_REQUEST);
+    }
+
+    #[test]
+    fn test_json_payload_error() {
+        let resp: HttpResponse = JsonPayloadError::Overflow.error_response();
+        assert_eq!(resp.status(), StatusCode::PAYLOAD_TOO_LARGE);
+        let resp: HttpResponse = JsonPayloadError::ContentType.error_response();
+        assert_eq!(resp.status(), StatusCode::BAD_REQUEST);
+    }
+
+    #[test]
+    fn test_readlines_error() {
+        let resp: HttpResponse = ReadlinesError::LimitOverflow.error_response();
+        assert_eq!(resp.status(), StatusCode::PAYLOAD_TOO_LARGE);
+        let resp: HttpResponse = ReadlinesError::EncodingError.error_response();
+        assert_eq!(resp.status(), StatusCode::BAD_REQUEST);
+    }
+}
diff --git a/src/responder.rs b/src/responder.rs
index 871670bdf..50467883c 100644
--- a/src/responder.rs
+++ b/src/responder.rs
@@ -380,6 +380,15 @@ pub(crate) mod tests {
             HeaderValue::from_static("text/plain; charset=utf-8")
         );
 
+        let resp: HttpResponse =
+            block_on((&"test".to_string()).respond_to(&req)).unwrap();
+        assert_eq!(resp.status(), StatusCode::OK);
+        assert_eq!(resp.body().bin_ref(), b"test");
+        assert_eq!(
+            resp.headers().get(CONTENT_TYPE).unwrap(),
+            HeaderValue::from_static("text/plain; charset=utf-8")
+        );
+
         let resp: HttpResponse =
             block_on(Bytes::from_static(b"test").respond_to(&req)).unwrap();
         assert_eq!(resp.status(), StatusCode::OK);
@@ -398,10 +407,32 @@ pub(crate) mod tests {
             HeaderValue::from_static("application/octet-stream")
         );
 
+        // InternalError
         let resp: HttpResponse =
             error::InternalError::new("err", StatusCode::BAD_REQUEST)
                 .respond_to(&req)
                 .unwrap();
         assert_eq!(resp.status(), StatusCode::BAD_REQUEST);
     }
+
+    #[test]
+    fn test_result_responder() {
+        let req = TestRequest::default().to_http_request();
+
+        // Result<I, E>
+        let resp: HttpResponse =
+            block_on(Ok::<_, Error>("test".to_string()).respond_to(&req)).unwrap();
+        assert_eq!(resp.status(), StatusCode::OK);
+        assert_eq!(resp.body().bin_ref(), b"test");
+        assert_eq!(
+            resp.headers().get(CONTENT_TYPE).unwrap(),
+            HeaderValue::from_static("text/plain; charset=utf-8")
+        );
+
+        let res = block_on(
+            Err::<String, _>(error::InternalError::new("err", StatusCode::BAD_REQUEST))
+                .respond_to(&req),
+        );
+        assert!(res.is_err());
+    }
 }