Fix some warnings in codegen + tests.

juniper_codegen/src/derive_object.rs

@@ -151,7 +151,7 @@ pub fn impl_object(ast: &syn::DeriveInput) -> Tokens {
                 Some(#name)
             }
 
-            fn concrete_type_name(&self, context: &Self::Context) -> String {
+            fn concrete_type_name(&self, _: &Self::Context) -> String {
                 #name.to_string()
             }
 
@@ -164,7 +164,7 @@ pub fn impl_object(ast: &syn::DeriveInput) -> Tokens {
                 builder.into_meta()
             }
 
-            fn resolve_field(&self, field_name: &str, args: &::juniper::Arguments, executor: &::juniper::Executor<Self::Context>)
+            fn resolve_field(&self, field_name: &str, _: &::juniper::Arguments, executor: &::juniper::Executor<Self::Context>)
                 -> ::juniper::ExecutionResult
             {
 

juniper_tests/src/codegen/derive_input_object.rs

@@ -1,4 +1,4 @@
-use juniper::{self, InputValue, ToInputValue, GraphQLType, FromInputValue};
+use juniper::{ToInputValue, GraphQLType, FromInputValue};
 
 #[derive(GraphQLInputObject, Debug, PartialEq)]
 #[graphql(name="MyInput")]

juniper_tests/src/codegen/derive_object.rs

@@ -1,4 +1,4 @@
-use juniper::{self, execute, GraphQLType, Value, Variables, EmptyMutation, RootNode};
+use juniper::{execute, GraphQLType, Value, Variables, EmptyMutation, RootNode};
 
 #[derive(GraphQLObject, Debug, PartialEq)]
 #[graphql(name="MyObj", description="obj descr")]

juniper_tests/src/lib.rs

@@ -1,5 +1,5 @@
 #[macro_use] extern crate juniper;
 #[macro_use] extern crate juniper_codegen;
-#[macro_use] extern crate serde_json;
+extern crate serde_json;
 
 mod codegen;