Add basic interface introspection tests

src/executor_tests/introspection.rs

@@ -9,6 +9,8 @@ enum Sample {
     Two,
 }
 
+struct Interface {}
+
 struct Root {}
 
 graphql_enum!(Sample as "SampleEnum" {
@@ -16,7 +18,21 @@ graphql_enum!(Sample as "SampleEnum" {
     Sample::Two => "TWO",
 });
 
+graphql_interface!(Interface: () as "SampleInterface" |&self| {
+    description: "A sample interface"
+    
+    field sample_enum() -> FieldResult<Sample> as "A sample field in the interface" {
+        Ok(Sample::One)
+    }
+
+    instance_resolvers: |&_| [
+        Some(Root {}),
+    ]
+});
+
 graphql_object!(Root: () as "Root" |&self| {
+    interfaces: [Interface]
+
     field sample_enum() -> FieldResult<Sample> {
         Ok(Sample::One)
     }
@@ -27,6 +43,9 @@ fn enum_introspection() {
     let doc = r#"
     {
         __type(name: "SampleEnum") {
+            name
+            kind
+            description
             enumValues {
                 name
                 description
@@ -45,10 +64,16 @@ fn enum_introspection() {
 
     println!("Result: {:?}", result);
 
-    let values = result
+    let type_info = result
         .as_object_value().expect("Result is not an object")
         .get("__type").expect("__type field missing")
-        .as_object_value().expect("__type field not an object value")
+        .as_object_value().expect("__type field not an object value");
+
+    assert_eq!(type_info.get("name"), Some(&Value::string("SampleEnum")));
+    assert_eq!(type_info.get("kind"), Some(&Value::string("ENUM")));
+    assert_eq!(type_info.get("description"), Some(&Value::null())); 
+
+    let values = type_info
         .get("enumValues").expect("enumValues field missing")
         .as_list_value().expect("enumValues not a list");
 
@@ -68,3 +93,85 @@ fn enum_introspection() {
         ("deprecationReason", Value::null()),
     ].into_iter().collect())));
 }
+
+#[test]
+fn interface_introspection() {
+    let doc = r#"
+    {
+        __type(name: "SampleInterface") {
+            name
+            kind
+            description
+            possibleTypes {
+                name
+            }
+            fields {
+                name
+                description
+                args {
+                    name
+                }
+                type {
+                    name
+                    kind
+                    ofType {
+                        name
+                        kind
+                    }
+                }
+                isDeprecated
+                deprecationReason
+            }
+        }
+    }
+    "#;
+    let schema = RootNode::new(Root {}, ());
+
+    let (result, errs) = ::execute(doc, None, &schema, &HashMap::new(), &())
+        .expect("Execution failed");
+
+    assert_eq!(errs, []);
+
+    println!("Result: {:?}", result);
+
+    let type_info = result
+        .as_object_value().expect("Result is not an object")
+        .get("__type").expect("__type field missing")
+        .as_object_value().expect("__type field not an object value");
+
+    assert_eq!(type_info.get("name"), Some(&Value::string("SampleInterface")));
+    assert_eq!(type_info.get("kind"), Some(&Value::string("INTERFACE")));
+    assert_eq!(type_info.get("description"), Some(&Value::string("A sample interface"))); 
+
+    let possible_types = type_info
+        .get("possibleTypes").expect("possibleTypes field missing")
+        .as_list_value().expect("possibleTypes not a list");
+
+    assert_eq!(possible_types.len(), 1);
+
+    assert!(possible_types.contains(&Value::object(vec![
+        ("name", Value::string("Root")),
+    ].into_iter().collect())));
+
+    let fields = type_info
+        .get("fields").expect("fields field missing")
+        .as_list_value().expect("fields field not an object value");
+
+    assert_eq!(fields.len(), 2);
+
+    assert!(fields.contains(&Value::object(vec![
+        ("name", Value::string("sampleEnum")),
+        ("description", Value::string("A sample field in the interface")),
+        ("args", Value::list(vec![])),
+        ("type", Value::object(vec![
+            ("name", Value::null()),
+            ("kind", Value::string("NON_NULL")),
+            ("ofType", Value::object(vec![
+                ("name", Value::string("SampleEnum")),
+                ("kind", Value::string("ENUM")),
+            ].into_iter().collect())),
+        ].into_iter().collect())),
+        ("isDeprecated", Value::boolean(false)),
+        ("deprecationReason", Value::null()),
+    ].into_iter().collect())));
+}