Initialisation

Added the packages and files for the backend server

node_modules/graphql/validation/rules/UniqueArgumentNamesRule.js

@@ -0,0 +1,55 @@
+'use strict';
+
+Object.defineProperty(exports, '__esModule', {
+  value: true,
+});
+exports.UniqueArgumentNamesRule = UniqueArgumentNamesRule;
+
+var _groupBy = require('../../jsutils/groupBy.js');
+
+var _GraphQLError = require('../../error/GraphQLError.js');
+
+/**
+ * Unique argument names
+ *
+ * A GraphQL field or directive is only valid if all supplied arguments are
+ * uniquely named.
+ *
+ * See https://spec.graphql.org/draft/#sec-Argument-Names
+ */
+function UniqueArgumentNamesRule(context) {
+  return {
+    Field: checkArgUniqueness,
+    Directive: checkArgUniqueness,
+  };
+
+  function checkArgUniqueness(parentNode) {
+    var _parentNode$arguments;
+
+    // FIXME: https://github.com/graphql/graphql-js/issues/2203
+
+    /* c8 ignore next */
+    const argumentNodes =
+      (_parentNode$arguments = parentNode.arguments) !== null &&
+      _parentNode$arguments !== void 0
+        ? _parentNode$arguments
+        : [];
+    const seenArgs = (0, _groupBy.groupBy)(
+      argumentNodes,
+      (arg) => arg.name.value,
+    );
+
+    for (const [argName, argNodes] of seenArgs) {
+      if (argNodes.length > 1) {
+        context.reportError(
+          new _GraphQLError.GraphQLError(
+            `There can be only one argument named "${argName}".`,
+            {
+              nodes: argNodes.map((node) => node.name),
+            },
+          ),
+        );
+      }
+    }
+  }
+}