diff --git a/Cargo.toml b/Cargo.toml
index 65ffad17..0b60a351 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "async-graphql"
-version = "1.7.3"
+version = "1.7.4"
 authors = ["sunli <scott_s829@163.com>"]
 edition = "2018"
 description = "The GraphQL server library implemented by rust"
@@ -18,7 +18,7 @@ default = ["bson", "uuid", "url", "chrono-tz", "validators"]
 validators = ["regex"]
 
 [dependencies]
-async-graphql-derive = { path = "async-graphql-derive", version = "1.7.3" }
+async-graphql-derive = { path = "async-graphql-derive", version = "1.7.4" }
 graphql-parser = "=0.2.3"
 anyhow = "1.0.26"
 thiserror = "1.0.11"
diff --git a/async-graphql-actix-web/Cargo.toml b/async-graphql-actix-web/Cargo.toml
index 3da2976b..454d3eb4 100644
--- a/async-graphql-actix-web/Cargo.toml
+++ b/async-graphql-actix-web/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "async-graphql-actix-web"
-version = "0.7.3"
+version = "0.7.4"
 authors = ["sunli <scott_s829@163.com>"]
 edition = "2018"
 description = "async-graphql for actix-web"
@@ -13,7 +13,7 @@ keywords = ["futures", "async", "graphql"]
 categories = ["network-programming", "asynchronous"]
 
 [dependencies]
-async-graphql = { path = "..", version = "1.7.3" }
+async-graphql = { path = "..", version = "1.7.4" }
 actix-web = "2.0.0"
 actix-multipart = "0.2.0"
 actix-web-actors = "2.0.0"
diff --git a/async-graphql-derive/Cargo.toml b/async-graphql-derive/Cargo.toml
index 4b6c5876..28f73e4f 100644
--- a/async-graphql-derive/Cargo.toml
+++ b/async-graphql-derive/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "async-graphql-derive"
-version = "1.7.3"
+version = "1.7.4"
 authors = ["sunli <scott_s829@163.com>"]
 edition = "2018"
 description = "Macros for async-graphql"
diff --git a/src/registry.rs b/src/registry.rs
index b9ea01ba..6c8de736 100644
--- a/src/registry.rs
+++ b/src/registry.rs
@@ -67,7 +67,7 @@ impl<'a> TypeName<'a> {
     pub fn unwrap_non_null(&self) -> Self {
         match self {
             TypeName::NonNull(ty) => TypeName::create(ty),
-            _ => self.clone(),
+            _ => *self,
         }
     }
 
diff --git a/src/validation/rules/variables_in_allowed_position.rs b/src/validation/rules/variables_in_allowed_position.rs
index 3d62ac5f..f8f36ae2 100644
--- a/src/validation/rules/variables_in_allowed_position.rs
+++ b/src/validation/rules/variables_in_allowed_position.rs
@@ -125,7 +125,7 @@ impl<'a> Visitor<'a> for VariableInAllowedPosition<'a> {
                     self.variable_usages
                         .entry(scope.clone())
                         .or_insert_with(Vec::new)
-                        .push((name.as_str(), pos, expected_type.clone()));
+                        .push((name.as_str(), pos, *expected_type));
                 }
             }
         }
diff --git a/src/validation/utils.rs b/src/validation/utils.rs
index 51d4b645..ede96259 100644
--- a/src/validation/utils.rs
+++ b/src/validation/utils.rs
@@ -166,10 +166,10 @@ pub fn is_valid_input_value(
                                 }
                             }
 
-                            for name in input_names {
+                            if let Some(name) = input_names.iter().next() {
                                 return Some(valid_error(
                                     &path_node,
-                                    format!("unknown field \"{}\" of type \"{}\"", name, ty.name(),),
+                                    format!("unknown field \"{}\" of type \"{}\"", name, ty.name()),
                                 ));
                             }
 
diff --git a/src/validation/visitor.rs b/src/validation/visitor.rs
index 1eaea30d..1fd974e5 100644
--- a/src/validation/visitor.rs
+++ b/src/validation/visitor.rs
@@ -633,7 +633,7 @@ fn visit_directives<'a, V: Visitor<'a>>(
             v.enter_argument(ctx, d.position, name, value);
             let expected_ty = schema_directive
                 .and_then(|schema_directive| schema_directive.args.get(name.as_str()))
-                .and_then(|input_ty| Some(TypeName::create(&input_ty.ty)));
+                .map(|input_ty| TypeName::create(&input_ty.ty));
             ctx.with_input_type(expected_ty, |ctx| {
                 visit_input_value(v, ctx, d.position, expected_ty, value)
             });