Implements Default for Schema.

src/schema.rs

@@ -153,6 +153,21 @@ impl<Query, Mutation, Subscription> Clone for Schema<Query, Mutation, Subscripti
     }
 }
 
+impl<Query, Mutation, Subscription> Default for Schema<Query, Mutation, Subscription>
+where
+    Query: Default + ObjectType + Send + Sync + 'static,
+    Mutation: Default + ObjectType + Send + Sync + 'static,
+    Subscription: Default + SubscriptionType + Send + Sync + 'static,
+{
+    fn default() -> Self {
+        Schema::new(
+            Query::default(),
+            Mutation::default(),
+            Subscription::default(),
+        )
+    }
+}
+
 impl<Query, Mutation, Subscription> Deref for Schema<Query, Mutation, Subscription>
 where
     Query: ObjectType + Send + Sync + 'static,

src/types/empty_mutation.rs

@@ -21,6 +21,7 @@ use std::borrow::Cow;
 ///
 /// let schema = Schema::new(QueryRoot, EmptyMutation, EmptySubscription);
 /// ```
+#[derive(Default, Copy, Clone)]
 pub struct EmptyMutation;
 
 impl Type for EmptyMutation {

src/types/empty_subscription.rs

@@ -7,6 +7,7 @@ use std::pin::Pin;
 /// Empty subscription
 ///
 /// Only the parameters used to construct the Schema, representing an unconfigured subscription.
+#[derive(Default, Copy, Clone)]
 pub struct EmptySubscription;
 
 impl Type for EmptySubscription {

tests/schema.rs

@@ -0,0 +1,11 @@
+use async_graphql::*;
+
+#[async_std::test]
+pub async fn test_schema_default() {
+    #[derive(GQLSimpleObject, Default)]
+    struct Query;
+
+    type MySchema = Schema<Query, EmptyMutation, EmptySubscription>;
+
+    let _schema = MySchema::default();
+}