attempt at parsing once

brigand · Aug 23, 2019 · 0f4c2cf · 0f4c2cf
1 parent d7f048e
commit 0f4c2cf
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Showing 4 changed files with 104 additions and 76 deletions.
diff --git a/package.json b/package.json
@@ -14,6 +14,7 @@
     "@babel/core": "^7.5.5",
     "@babel/generator": "^7.5.5",
     "@babel/parser": "^7.5.5",
+    "@babel/plugin-proposal-async-generator-functions": "^7.2.0",
     "@babel/plugin-proposal-class-properties": "^7.1.0",
     "@babel/plugin-proposal-decorators": "^7.4.4",
     "@babel/plugin-proposal-do-expressions": "^7.0.0",
@@ -31,6 +32,7 @@
     "@babel/plugin-proposal-partial-application": "^7.4.4",
     "@babel/plugin-proposal-pipeline-operator": "^7.0.0",
     "@babel/plugin-proposal-throw-expressions": "^7.2.0",
+    "@babel/plugin-proposal-unicode-property-regex": "^7.4.4",
     "@babel/plugin-syntax-bigint": "^7.0.0",
     "@babel/plugin-syntax-import-meta": "^7.0.0",
     "@babel/plugin-transform-modules-commonjs": "^7.5.0",

diff --git a/src/plugins/js-eval/babelPlugins.js b/src/plugins/js-eval/babelPlugins.js
@@ -0,0 +1,54 @@
+// all babel proposal plugins https://github.com/babel/babel/tree/master/packages (preset-stage-n packages are depreacted https://babeljs.io/docs/en/next/babel-preset-stage-1)
+// if there are new ones, feel free to add them
+exports.transformPlugins = [
+  '@babel/plugin-proposal-async-generator-functions',
+  '@babel/plugin-transform-typescript',
+  '@babel/plugin-transform-modules-commonjs', // required by dynamicImport
+  ['@babel/plugin-proposal-decorators', { decoratorsBeforeExport: false }], // must be before class-properties https://babeljs.io/docs/en/babel-plugin-proposal-decorators#note-compatibility-with-babel-plugin-proposal-class-properties
+  '@babel/plugin-proposal-class-properties',
+  '@babel/plugin-proposal-do-expressions',
+  '@babel/plugin-proposal-export-default-from',
+  '@babel/plugin-proposal-export-namespace-from',
+  '@babel/plugin-proposal-function-sent',
+  '@babel/plugin-proposal-function-bind',
+  '@babel/plugin-proposal-json-strings',
+  '@babel/plugin-proposal-logical-assignment-operators',
+  '@babel/plugin-proposal-nullish-coalescing-operator',
+  '@babel/plugin-proposal-numeric-separator',
+  '@babel/plugin-proposal-optional-catch-binding',
+  '@babel/plugin-proposal-optional-chaining',
+  '@babel/plugin-proposal-partial-application',
+  ['@babel/plugin-proposal-pipeline-operator', { proposal: 'minimal' }],
+  '@babel/plugin-proposal-throw-expressions',
+  '@babel/plugin-proposal-dynamic-import',
+  '@babel/plugin-syntax-bigint',
+  '@babel/plugin-syntax-import-meta',
+  '@babel/plugin-proposal-unicode-property-regex'
+];
+
+
+// @babel/parser plugins https://babeljs.io/docs/en/next/babel-parser.html#ecmascript-proposals-https-githubcom-babel-proposals
+exports.parserPlugins = [
+  'asyncGenerators',
+  'bigInt',
+  ['decorators', { decoratorsBeforeExport: true }],
+  'classProperties',
+  'classPrivateProperties',
+  'classPrivateMethods',
+  'doExpressions',
+  'dynamicImport',
+  'exportDefaultFrom',
+  'exportNamespaceFrom',
+  'functionBind',
+  'functionSent',
+  'importMeta',
+  'logicalAssignment',
+  'nullishCoalescingOperator',
+  'numericSeparator',
+  // 'objectRestSpread', // no need, node has it since a long time
+  'optionalCatchBinding',
+  'optionalChaining',
+  'partialApplication',
+  ['pipelineOperator', { proposal: 'minimal' }],
+  'throwExpressions'
+]
diff --git a/src/plugins/js-eval/jsEvalPlugin.js b/src/plugins/js-eval/jsEvalPlugin.js
@@ -1,56 +1,41 @@
 const cp = require('child_process');
 const babel = require('@babel/core');
+const babelGenerator = require('@babel/generator').default;
 const jsEval = require('./jsEval');
 const processTopLevelAwait = require('./processTopLevelAwait');
+const { transformPlugins } = require('./babelPlugins');
 
-const helpMsg = `n> node stable, h> node harmony, b> babel, s> node vm.Script, m> node vm.SourceTextModule, e> engine262`;
+
+const helpMsg = `n> node stable, h> node --harmony, b> babel, s> node vm.Script, m> node vm.SourceTextModule, e> engine262`;
 
 // default jseval run command
 const CMD = ['node', '--no-warnings', '/run/run.js'];
 const CMD_SHIMS = ['node', '-r', '/run/node_modules/airbnb-js-shims/target/es2019', '/run/run.js'];
 const CMD_HARMONY = ['node', '--harmony', '--experimental-vm-modules', '--experimental-modules', '--no-warnings', '/run/run.js'];
 
-const babelTransformOpts = {
-  parserOpts: {
-    allowAwaitOutsideFunction: true,
-    allowReturnOutsideFunction: true,
-  },
-  plugins: [
-    '@babel/plugin-transform-typescript',
-    '@babel/plugin-transform-modules-commonjs', // required by dynamicImport
-    ['@babel/plugin-proposal-decorators', { decoratorsBeforeExport: false }], // must be before class-properties https://babeljs.io/docs/en/babel-plugin-proposal-decorators#note-compatibility-with-babel-plugin-proposal-class-properties
-    '@babel/plugin-proposal-class-properties',
-    '@babel/plugin-proposal-do-expressions',
-    '@babel/plugin-proposal-export-default-from',
-    '@babel/plugin-proposal-export-namespace-from',
-    '@babel/plugin-proposal-function-sent',
-    '@babel/plugin-proposal-function-bind',
-    '@babel/plugin-proposal-json-strings',
-    '@babel/plugin-proposal-logical-assignment-operators',
-    '@babel/plugin-proposal-nullish-coalescing-operator',
-    '@babel/plugin-proposal-numeric-separator',
-    '@babel/plugin-proposal-optional-catch-binding',
-    '@babel/plugin-proposal-optional-chaining',
-    '@babel/plugin-proposal-partial-application',
-    ['@babel/plugin-proposal-pipeline-operator', { proposal: 'minimal' }],
-    '@babel/plugin-proposal-throw-expressions',
-    '@babel/plugin-proposal-dynamic-import',
-    '@babel/plugin-syntax-bigint',
-    '@babel/plugin-syntax-import-meta',
-  ]
-};
 
 const jsEvalPlugin = async ({ mentionUser, respond, message, selfConfig = {} }) => {
   if (!/^[nhbsme?]>/.test(message)) return;
   const mode = message[0];
   if (mode === '?') return respond((mentionUser ? `${mentionUser}, ` : '') + helpMsg);
   let code = message.slice(2);
 
-  if (mode === 'b') {
-    code = (await babel.transformAsync(code, babelTransformOpts)).code;
+  const hasMaybeTLA = /\bawait\b/.test(code);
+
+  if (mode === 'b' && !hasMaybeTLA) {
+    code = (await babel.transformAsync(code, { plugins: transformPlugins })).code;
   }
 
-  code = processTopLevelAwait(code) || code; // it returns null when no TLA is found
+  if (hasMaybeTLA) { // there's maybe a TLA await
+    const iiafe = processTopLevelAwait(code);
+    if (iiafe) { // there's a TLA
+      if (mode === 'b') {
+        code = (await babel.transformFromAstAsync(iiafe, code, { plugins: transformPlugins })).code;
+      } else {
+        code = babelGenerator(iiafe).code;
+      }
+    }
+  }
 
   try {
     const result = await jsEval(

diff --git a/src/plugins/js-eval/processTopLevelAwait.js b/src/plugins/js-eval/processTopLevelAwait.js
@@ -1,41 +1,20 @@
 const babelParser = require('@babel/parser');
 const babelTraverse = require('@babel/traverse').default;
-const babelGenerator = require('@babel/generator').default;
-
-const babelParseOpts = {
-  allowAwaitOutsideFunction: true,
-  plugins: [
-    'throwExpressions',
-    'bigInt',
-    ['decorators', { decoratorsBeforeExport: true }],
-    'classProperties',
-    'classPrivateProperties',
-    'classPrivateMethods',
-    'doExpressions',
-    'dynamicImport',
-    'exportDefaultFrom',
-    'exportNamespaceFrom',
-    'functionBind',
-    'functionSent',
-    'importMeta',
-    'logicalAssignment',
-    'nullishCoalescingOperator',
-    'numericSeparator',
-    // 'objectRestSpread',
-    'optionalCatchBinding',
-    'optionalChaining',
-    'partialApplication',
-    ['pipelineOperator', { proposal: 'minimal' }],
-    'throwExpressions'
-  ]
-};
-
+const { parserPlugins } = require('./babelPlugins');
 
+/**
+ * 
+ * @param {string} src 
+ * @return {object} ast
+ */
 function processTopLevelAwait(src) {
   let root;
 
   try {
-    root = babelParser.parse(src, babelParseOpts);
+    root = babelParser.parse(src, {
+      allowAwaitOutsideFunction: true,
+      plugins: parserPlugins
+    });
   } catch (error) {
     return null; // if code is not valid, don't bother
   }
@@ -90,20 +69,28 @@ function processTopLevelAwait(src) {
   };
 
   const iiafe = {
-    type: 'CallExpression',
-    callee: {
-      type: 'ArrowFunctionExpression',
-      async: true,
-      params: [],
-      body: {
-        type: 'BlockStatement',
-        body: root.program.body
-      },
-    },
-    arguments: []
+    type: 'Program',
+    sourceType: 'script',
+    body: [{
+      type: 'ExpressionStatement',
+      expression: {
+        type: 'CallExpression',
+        callee: {
+          type: 'ArrowFunctionExpression',
+          async: true,
+          params: [],
+          body: {
+            type: 'BlockStatement',
+            body: root.program.body
+          },
+        },
+        arguments: []
+      }
+    }],
   };
+  // const iiafe = t.program([t.expressionStatement(t.callExpression(t.arrowFunctionExpression([], t.blockStatement(root.program.body)), []))]) // with @babel/types
 
-  return babelGenerator(iiafe).code;
+  return iiafe;
 }
 
 module.exports = processTopLevelAwait;