[utils] [new] add visit, to support dynamic imports

See import-js#1660, import-js#2212.

Co-authored-by: Max Komarychev <maxkomarychev@gmail.com>
Co-authored-by: Filipp Riabchun <filipp.riabchun@jetbrains.com>
Co-authored-by: 薛定谔的猫 <weiran.zsd@outlook.com>

tests/src/core/getExports.js

@@ -8,7 +8,7 @@ import ExportMap from '../../../src/ExportMap';
 import * as fs from 'fs';
 
 import { getFilename } from '../utils';
-import * as unambiguous from 'eslint-module-utils/unambiguous';
+import { test as testUnambiguous } from 'eslint-module-utils/unambiguous';
 
 describe('ExportMap', function () {
   const fakeContext = Object.assign(
@@ -438,7 +438,6 @@ describe('ExportMap', function () {
 
   // todo: move to utils
   describe('unambiguous regex', function () {
-
     const testFiles = [
       ['deep/b.js', true],
       ['bar.js', true],
@@ -449,10 +448,8 @@ describe('ExportMap', function () {
     for (const [testFile, expectedRegexResult] of testFiles) {
       it(`works for ${testFile} (${expectedRegexResult})`, function () {
         const content = fs.readFileSync('./tests/files/' + testFile, 'utf8');
-        expect(unambiguous.test(content)).to.equal(expectedRegexResult);
+        expect(testUnambiguous(content)).to.equal(expectedRegexResult);
       });
     }
-
   });
-
 });

tests/src/core/parse.js

@@ -69,5 +69,4 @@ describe('parse(content, { settings, ecmaFeatures })', function () {
     expect(parse.bind(null, path, content, { settings: { 'import/parsers': { [parseStubParserPath]: [ '.js' ] } }, parserPath: null, parserOptions })).not.to.throw(Error);
     expect(parseSpy.callCount, 'custom parser to be called once').to.equal(1);
   });
-
 });

utils/CHANGELOG.md

@@ -7,6 +7,7 @@ This change log adheres to standards from [Keep a CHANGELOG](http://keepachangel
 
 ### Added
 - `fileExistsWithCaseSync`: add `strict` argument ([#1262], thanks [@sergei-startsev])
+- add `visit`, to support dynamic imports ([#1660], [#2212], thanks [@maxkomarychev], [@aladdin-add], [@Hypnosphi])
 
 ## v2.6.2 - 2021-08-08
 
@@ -93,10 +94,12 @@ Yanked due to critical issue with cache key resulting from #839.
 ### Fixed
 - `unambiguous.test()` regex is now properly in multiline mode
 
+[#2212]: https://github.com/import-js/eslint-plugin-import/pull/2212
 [#2160]: https://github.com/import-js/eslint-plugin-import/pull/2160
 [#2026]: https://github.com/import-js/eslint-plugin-import/pull/2026
 [#1786]: https://github.com/import-js/eslint-plugin-import/pull/1786
 [#1671]: https://github.com/import-js/eslint-plugin-import/pull/1671
+[#1660]: https://github.com/import-js/eslint-plugin-import/pull/1660
 [#1606]: https://github.com/import-js/eslint-plugin-import/pull/1606
 [#1602]: https://github.com/import-js/eslint-plugin-import/pull/1602
 [#1591]: https://github.com/import-js/eslint-plugin-import/pull/1591
@@ -126,4 +129,7 @@ Yanked due to critical issue with cache key resulting from #839.
 [@sergei-startsev]: https://github.com/sergei-startsev
 [@sompylasar]: https://github.com/sompylasar
 [@timkraut]: https://github.com/timkraut
-[@vikr01]: https://github.com/vikr01
+[@vikr01]: https://github.com/vikr01
+[@maxkomarychev]: https://github.com/maxkomarychev
+[@aladdin-add]: https://github.com/aladdin-add
+[@Hypnosphi]: https://github.com/Hypnosphi

utils/parse.js

@@ -3,9 +3,42 @@ exports.__esModule = true;
 
 const moduleRequire = require('./module-require').default;
 const extname = require('path').extname;
+const fs = require('fs');
 
 const log = require('debug')('eslint-plugin-import:parse');
 
+function getBabelVisitorKeys(parserPath) {
+  if (parserPath.endsWith('index.js')) {
+    const hypotheticalLocation = parserPath.replace('index.js', 'visitor-keys.js');
+    if (fs.existsSync(hypotheticalLocation)) {
+      const keys = moduleRequire(hypotheticalLocation);
+      return keys.default || keys;
+    }
+  } else if (parserPath.endsWith('index.cjs')) {
+    const hypotheticalLocation = parserPath.replace('index.cjs', 'worker/ast-info.cjs');
+    if (fs.existsSync(hypotheticalLocation)) {
+      const astInfo = moduleRequire(hypotheticalLocation);
+      return astInfo.getVisitorKeys();
+    }
+  }
+  return null;
+}
+
+function keysFromParser(parserPath, parserInstance, parsedResult) {
+  if (/.*espree.*/.test(parserPath)) {
+    return parserInstance.VisitorKeys;
+  }
+  if (/.*(babel-eslint|@babel\/eslint-parser).*/.test(parserPath)) {
+    return getBabelVisitorKeys(parserPath);
+  }
+  if (/.*@typescript-eslint\/parser/.test(parserPath)) {
+    if (parsedResult) {
+      return parsedResult.visitorKeys;
+    }
+  }
+  return null;
+}
+
 exports.default = function parse(path, content, context) {
 
   if (context == null) throw new Error('need context to parse properly');
@@ -45,20 +78,36 @@ exports.default = function parse(path, content, context) {
   if (typeof parser.parseForESLint === 'function') {
     let ast;
     try {
-      ast = parser.parseForESLint(content, parserOptions).ast;
+      const parserRaw = parser.parseForESLint(content, parserOptions);
+      ast = parserRaw.ast;
+      return {
+        ast,
+        visitorKeys: keysFromParser(parserPath, parser, parserRaw),
+      };
     } catch (e) {
       console.warn();
       console.warn('Error while parsing ' + parserOptions.filePath);
       console.warn('Line ' + e.lineNumber + ', column ' + e.column + ': ' + e.message);
     }
     if (!ast || typeof ast !== 'object') {
-      console.warn('`parseForESLint` from parser `' + parserPath + '` is invalid and will just be ignored');
+      console.warn(
+        '`parseForESLint` from parser `' +
+          parserPath +
+          '` is invalid and will just be ignored',
+      );
     } else {
-      return ast;
+      return {
+        ast,
+        visitorKeys: keysFromParser(parserPath, parser, undefined),
+      };
     }
   }
 
-  return parser.parse(content, parserOptions);
+  const keys = keysFromParser(parserPath, parser, undefined);
+  return {
+    ast: parser.parse(content, parserOptions),
+    visitorKeys: keys,
+  };
 };
 
 function getParserPath(path, context) {

utils/unambiguous.js

@@ -1,8 +1,7 @@
 'use strict';
 exports.__esModule = true;
 
-
-const pattern = /(^|;)\s*(export|import)((\s+\w)|(\s*[{*=]))/m;
+const pattern = /(^|;)\s*(export|import)((\s+\w)|(\s*[{*=]))|import\(/m;
 /**
  * detect possible imports/exports without a full parse.
  *
@@ -26,5 +25,5 @@ const unambiguousNodeType = /^(?:(?:Exp|Imp)ort.*Declaration|TSExportAssignment)
  * @return {Boolean}
  */
 exports.isModule = function isUnambiguousModule(ast) {
-  return ast.body.some(node => unambiguousNodeType.test(node.type));
+  return ast.body && ast.body.some(node => unambiguousNodeType.test(node.type));
 };

utils/visit.js

@@ -0,0 +1,24 @@
+'use strict';
+exports.__esModule = true;
+
+exports.default = function visit(node, keys, visitorSpec) {
+  if (!node || !keys) {
+    return;
+  }
+  const type = node.type;
+  if (typeof visitorSpec[type] === 'function') {
+    visitorSpec[type](node);
+  }
+  const childFields = keys[type];
+  if (!childFields) {
+    return;
+  }
+  childFields.forEach((fieldName) => {
+    [].concat(node[fieldName]).forEach((item) => {
+      visit(item, keys, visitorSpec);
+    });
+  });
+  if (typeof visitorSpec[`${type}:Exit`] === 'function') {
+    visitorSpec[`${type}:Exit`](node);
+  }
+};