[optimizer] validate the syntax of bundled node_modules

packages/kbn-optimizer/package.json

@@ -14,9 +14,12 @@
     "@kbn/babel-preset": "1.0.0",
     "@kbn/dev-utils": "1.0.0",
     "@kbn/ui-shared-deps": "1.0.0",
+    "@types/estree": "^0.0.44",
     "@types/loader-utils": "^1.1.3",
     "@types/watchpack": "^1.1.5",
     "@types/webpack": "^4.41.3",
+    "acorn": "^7.1.1",
+    "acorn-walk": "^7.1.1",
     "autoprefixer": "^9.7.4",
     "babel-loader": "^8.0.6",
     "clean-webpack-plugin": "^3.0.0",

packages/kbn-optimizer/src/common/disallowed_syntax_plugin/disallowed_syntax.ts

@@ -0,0 +1,194 @@
+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import estree from 'estree';
+
+export interface DisallowedSyntaxCheck {
+  name: string;
+  nodeType: estree.Node['type'] | Array<estree.Node['type']>;
+  test?: (n: any) => boolean | void;
+}
+
+export const checks: DisallowedSyntaxCheck[] = [
+  /**
+   * es2015
+   */
+  // https://github.com/estree/estree/blob/master/es2015.md#functions
+  {
+    name: '[es2015] generator function',
+    nodeType: ['FunctionDeclaration', 'FunctionExpression'],
+    test: (n: estree.FunctionDeclaration | estree.FunctionExpression) => !!n.generator,
+  },
+  // https://github.com/estree/estree/blob/master/es2015.md#forofstatement
+  {
+    name: '[es2015] for-of statement',
+    nodeType: 'ForOfStatement',
+  },
+  // https://github.com/estree/estree/blob/master/es2015.md#variabledeclaration
+  {
+    name: '[es2015] let/const variable declaration',
+    nodeType: 'VariableDeclaration',
+    test: (n: estree.VariableDeclaration) => n.kind === 'let' || n.kind === 'const',
+  },
+  // https://github.com/estree/estree/blob/master/es2015.md#expressions
+  {
+    name: '[es2015] `super`',
+    nodeType: 'Super',
+  },
+  // https://github.com/estree/estree/blob/master/es2015.md#expressions
+  {
+    name: '[es2015] ...spread',
+    nodeType: 'SpreadElement',
+  },
+  // https://github.com/estree/estree/blob/master/es2015.md#arrowfunctionexpression
+  {
+    name: '[es2015] arrow function expression',
+    nodeType: 'ArrowFunctionExpression',
+  },
+  // https://github.com/estree/estree/blob/master/es2015.md#yieldexpression
+  {
+    name: '[es2015] `yield` expression',
+    nodeType: 'YieldExpression',
+  },
+  // https://github.com/estree/estree/blob/master/es2015.md#templateliteral
+  {
+    name: '[es2015] template literal',
+    nodeType: 'TemplateLiteral',
+  },
+  // https://github.com/estree/estree/blob/master/es2015.md#patterns
+  {
+    name: '[es2015] destructuring',
+    nodeType: ['ObjectPattern', 'ArrayPattern', 'AssignmentPattern'],
+  },
+  // https://github.com/estree/estree/blob/master/es2015.md#classes
+  {
+    name: '[es2015] class',
+    nodeType: [
+      'ClassDeclaration',
+      'ClassExpression',
+      'ClassBody',
+      'MethodDefinition',
+      'MetaProperty',
+    ],
+  },
+
+  /**
+   * es2016
+   */
+  {
+    name: '[es2016] exponent operator',
+    nodeType: 'BinaryExpression',
+    test: (n: estree.BinaryExpression) => n.operator === '**',
+  },
+  {
+    name: '[es2016] exponent assignment',
+    nodeType: 'AssignmentExpression',
+    test: (n: estree.AssignmentExpression) => n.operator === '**=',
+  },
+
+  /**
+   * es2017
+   */
+  // https://github.com/estree/estree/blob/master/es2017.md#function
+  {
+    name: '[es2017] async function',
+    nodeType: ['FunctionDeclaration', 'FunctionExpression'],
+    test: (n: estree.FunctionDeclaration | estree.FunctionExpression) => n.async,
+  },
+  // https://github.com/estree/estree/blob/master/es2017.md#awaitexpression
+  {
+    name: '[es2017] await expression',
+    nodeType: 'AwaitExpression',
+  },
+
+  /**
+   * es2018
+   */
+  // https://github.com/estree/estree/blob/master/es2018.md#statements
+  {
+    name: '[es2018] for-await-of statements',
+    nodeType: 'ForOfStatement',
+    test: (n: estree.ForOfStatement) => n.await,
+  },
+  // https://github.com/estree/estree/blob/master/es2018.md#expressions
+  {
+    name: '[es2018] object spread properties',
+    nodeType: 'ObjectExpression',
+    test: (n: estree.ObjectExpression) => n.properties.some(p => p.type === 'SpreadElement'),
+  },
+  // https://github.com/estree/estree/blob/master/es2018.md#template-literals
+  {
+    name: '[es2018] tagged template literal with invalid escape',
+    nodeType: 'TemplateElement',
+    test: (n: estree.TemplateElement) => n.value.cooked === null,
+  },
+  // https://github.com/estree/estree/blob/master/es2018.md#patterns
+  {
+    name: '[es2018] rest properties',
+    nodeType: 'ObjectPattern',
+    test: (n: estree.ObjectPattern) => n.properties.some(p => p.type === 'RestElement'),
+  },
+
+  /**
+   * es2019
+   */
+  // https://github.com/estree/estree/blob/master/es2019.md#catchclause
+  {
+    name: '[es2019] catch clause without a binding',
+    nodeType: 'CatchClause',
+    test: (n: estree.CatchClause) => !n.param,
+  },
+
+  /**
+   * es2020
+   */
+  // https://github.com/estree/estree/blob/master/es2020.md#bigintliteral
+  {
+    name: '[es2020] bigint literal',
+    nodeType: 'Literal',
+    test: (n: estree.Literal) => typeof n.value === 'bigint',
+  },
+
+  /**
+   * webpack transforms import/export in order to support tree shaking and async imports
+   *
+   * // https://github.com/estree/estree/blob/master/es2020.md#importexpression
+   * {
+   *   name: '[es2020] import expression',
+   *   nodeType: 'ImportExpression',
+   * },
+   * // https://github.com/estree/estree/blob/master/es2020.md#exportalldeclaration
+   * {
+   *   name: '[es2020] export all declaration',
+   *   nodeType: 'ExportAllDeclaration',
+   * },
+   *
+   */
+];
+
+export const checksByNodeType = new Map<estree.Node['type'], DisallowedSyntaxCheck[]>();
+for (const check of checks) {
+  const nodeTypes = Array.isArray(check.nodeType) ? check.nodeType : [check.nodeType];
+  for (const nodeType of nodeTypes) {
+    if (!checksByNodeType.has(nodeType)) {
+      checksByNodeType.set(nodeType, []);
+    }
+    checksByNodeType.get(nodeType)!.push(check);
+  }
+}