integrationTests: Add test for webpack (#3188)

Motivated by #3178

.eslintrc.yml

@@ -630,6 +630,7 @@ overrides:
     rules:
       node/no-sync: off
       node/no-missing-require: [error, { allowModules: ['graphql'] }]
+      import/no-commonjs: off
       import/no-nodejs-modules: off
       no-console: off
   - files: 'benchmark/**'

integrationTests/integration-test.js

@@ -42,4 +42,8 @@ describe('Integration Tests', () => {
   it('Should work on all supported node versions', () => {
     testOnNodeProject('node');
   }).timeout(40000);
+
+  it('Should be compatible with Webpack', () => {
+    testOnNodeProject('webpack');
+  }).timeout(40000);
 });

integrationTests/webpack/entry.js

@@ -0,0 +1,13 @@
+'use strict';
+
+const { buildSchema, graphqlSync } = require('graphql');
+
+const schema = buildSchema('type Query { hello: String }');
+
+const result = graphqlSync({
+  schema,
+  source: '{ hello }',
+  rootValue: { hello: 'world' },
+});
+
+module.exports = { result };

integrationTests/webpack/package.json

@@ -0,0 +1,11 @@
+{
+  "private": true,
+  "scripts": {
+    "test": "webpack && node test.js"
+  },
+  "dependencies": {
+    "graphql": "file:../graphql.tgz",
+    "webpack": "5.x.x",
+    "webpack-cli": "4.x.x"
+  }
+}

integrationTests/webpack/test.js

@@ -0,0 +1,14 @@
+'use strict';
+
+const assert = require('assert');
+
+// eslint-disable-next-line node/no-missing-require
+const { result } = require('./dist/main.js');
+
+assert.deepStrictEqual(result, {
+  data: {
+    __proto__: null,
+    hello: 'world',
+  },
+});
+console.log('Test script: Got correct result from Webpack bundle!');

integrationTests/webpack/webpack.config.json

@@ -0,0 +1,7 @@
+{
+  "mode": "production",
+  "entry": "./entry.js",
+  "output": {
+    "libraryTarget": "commonjs2"
+  }
+}