GraphQL: Implement schema (#2316)

src/printer-graphql.js

@@ -334,6 +334,32 @@ function genericPrint(path, options, print) {
       ]);
     }
 
+    case "SchemaDefinition": {
+      return concat([
+        "schema",
+        printDirectives(path, print, n),
+        " {",
+        n.operationTypes.length > 0
+          ? indent(
+              concat([
+                hardline,
+                join(hardline, path.map(print, "operationTypes"))
+              ])
+            )
+          : "",
+        hardline,
+        "}"
+      ]);
+    }
+
+    case "OperationTypeDefinition": {
+      return concat([
+        path.call(print, "operation"),
+        ": ",
+        path.call(print, "type")
+      ]);
+    }
+
     case "InterfaceTypeDefinition": {
       return concat([
         "interface ",

tests/graphql_schema/__snapshots__/jsfmt.spec.js.snap

@@ -0,0 +1,16 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`schema.graphql 1`] = `
+schema {
+  query: Root
+  mutation: Mutation
+  subscription: Subscription
+}
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+schema {
+  query: Root
+  mutation: Mutation
+  subscription: Subscription
+}
+
+`;

tests/graphql_schema/jsfmt.spec.js

@@ -0,0 +1 @@
+run_spec(__dirname, { parser: "graphql" });

tests/graphql_schema/schema.graphql

@@ -0,0 +1,5 @@
+schema {
+  query: Root
+  mutation: Mutation
+  subscription: Subscription
+}