fix false negative case for no-undefined-variables rule (#659)

Co-authored-by: Dotan Simha <dotansimha@gmail.com>

.changeset/hungry-kings-hammer.md

@@ -0,0 +1,5 @@
+---
+'@graphql-eslint/eslint-plugin': minor
+---
+
+fix false negative case for `no-undefined-variables` rule

packages/plugin/src/rules/graphql-js-validation.ts

@@ -216,9 +216,14 @@ export const GRAPHQL_JS_VALIDATIONS = Object.assign(
   validationToRule('no-fragment-cycles', 'NoFragmentCycles', {
     description: `A GraphQL fragment is only valid when it does not have cycles in fragments usage.`,
   }),
-  validationToRule('no-undefined-variables', 'NoUndefinedVariables', {
-    description: `A GraphQL operation is only valid if all variables encountered, both directly and via fragment spreads, are defined by that operation.`,
-  }),
+  validationToRule(
+    'no-undefined-variables',
+    'NoUndefinedVariables',
+    {
+      description: `A GraphQL operation is only valid if all variables encountered, both directly and via fragment spreads, are defined by that operation.`,
+    },
+    importFiles
+  ),
   validationToRule(
     'no-unused-fragments',
     'NoUnusedFragments',

packages/plugin/tests/mocks/no-undefined-variables.gql

@@ -0,0 +1,8 @@
+#import UserFields from './user-fields-with-variables.gql'
+
+query User {
+  user {
+    id
+    ...UserFields
+  }
+}

packages/plugin/tests/mocks/no-unused-variables.gql

@@ -1,4 +1,4 @@
-#import UserFields from './no-unused-variables-imported.gql'
+#import UserFields from './user-fields-with-variables.gql'
 
 query User($limit: Int!, $offset: Int!) {
   user {

packages/plugin/tests/mocks/user-fields-with-variables.gql

@@ -0,0 +1,6 @@
+fragment UserFields on User {
+  firstName
+  posts(limit: $limit, offset: $offset) {
+    id
+  }
+}

packages/plugin/tests/no-undefined-variables.spec.ts

@@ -0,0 +1,21 @@
+import { join } from 'path';
+import { GraphQLRuleTester, rules } from '../src';
+
+const ruleTester = new GraphQLRuleTester();
+
+ruleTester.runGraphQLTests('no-undefined-variables', rules['no-undefined-variables'], {
+  valid: [],
+  invalid: [
+    {
+      filename: join(__dirname, 'mocks/no-undefined-variables.gql'),
+      code: ruleTester.fromMockFile('no-undefined-variables.gql'),
+      parserOptions: {
+        schema: join(__dirname, 'mocks/user-schema.graphql'),
+      },
+      errors: [
+        { message: 'Variable "$limit" is not defined by operation "User".' },
+        { message: 'Variable "$offset" is not defined by operation "User".' },
+      ],
+    },
+  ],
+});