repl: display dynamic import variant in static import error messages

Enhance the REPL message for static import error message.

```
> import {foo, bar} from 'moo';
import {foo, bar} from 'moo';
^^^^^^

Uncaught:
SyntaxError: .* dynamic import: const {foo,bar} = await import('moo');
```

Author: hemanth

lib/repl.js

@@ -58,6 +58,7 @@ const {
   ArrayPrototypeSome,
   ArrayPrototypeSort,
   ArrayPrototypeSplice,
+  ArrayPrototypeToString,
   ArrayPrototypeUnshift,
   Boolean,
   Error,
@@ -104,7 +105,12 @@ const {
 const {
   isIdentifierStart,
   isIdentifierChar,
+  parse: acornParse,
 } = require('internal/deps/acorn/acorn/dist/acorn');
+
+
+const acornWalk = require('internal/deps/acorn/acorn-walk/dist/walk');
+
 const {
   decorateErrorStack,
   isError,
@@ -223,6 +229,29 @@ module.paths = CJSModule._nodeModulePaths(module.filename);
 const writer = (obj) => inspect(obj, writer.options);
 writer.options = { ...inspect.defaultOptions, showProxy: true };
 
+// Converts static import statement to dynamic import statement
+const toDynamicImport = (codeLine) => {
+  let dynamicImportStatement = '';
+  let moduleName = '';
+  const toCamelCase = (str) => str.replace(/[-_](\w)/g, (_, c) => c.toUpperCase());
+  const ast = acornParse(codeLine, { sourceType: 'module', ecmaVersion: 'latest' });
+  acornWalk.ancestor(ast, {
+    ImportDeclaration: (node) => {
+      const importedModules = node.source.value;
+      const importedSpecifiers = node.specifiers.map((specifier) => specifier.local.name);
+      if (importedSpecifiers.length > 1) {
+        moduleName = `{${importedSpecifiers.join(',')}}`;
+      } else {
+        const formattedSpecifiers = importedSpecifiers.length ? ArrayPrototypeToString(importedSpecifiers) : '';
+        moduleName = toCamelCase(formattedSpecifiers || importedModules);
+      }
+      dynamicImportStatement += `const ${moduleName} = await import('${importedModules}');`;
+    },
+  });
+  return dynamicImportStatement;
+};
+
+
 function REPLServer(prompt,
                     stream,
                     eval_,
@@ -283,13 +312,13 @@ function REPLServer(prompt,
     get: pendingDeprecation ?
       deprecate(() => this.input,
                 'repl.inputStream and repl.outputStream are deprecated. ' +
-                  'Use repl.input and repl.output instead',
+        'Use repl.input and repl.output instead',
                 'DEP0141') :
       () => this.input,
     set: pendingDeprecation ?
       deprecate((val) => this.input = val,
                 'repl.inputStream and repl.outputStream are deprecated. ' +
-                  'Use repl.input and repl.output instead',
+        'Use repl.input and repl.output instead',
                 'DEP0141') :
       (val) => this.input = val,
     enumerable: false,
@@ -300,13 +329,13 @@ function REPLServer(prompt,
     get: pendingDeprecation ?
       deprecate(() => this.output,
                 'repl.inputStream and repl.outputStream are deprecated. ' +
-                  'Use repl.input and repl.output instead',
+        'Use repl.input and repl.output instead',
                 'DEP0141') :
       () => this.output,
     set: pendingDeprecation ?
       deprecate((val) => this.output = val,
                 'repl.inputStream and repl.outputStream are deprecated. ' +
-                  'Use repl.input and repl.output instead',
+        'Use repl.input and repl.output instead',
                 'DEP0141') :
       (val) => this.output = val,
     enumerable: false,
@@ -344,9 +373,9 @@ function REPLServer(prompt,
     // instance and that could trigger the `MaxListenersExceededWarning`.
     process.prependListener('newListener', (event, listener) => {
       if (event === 'uncaughtException' &&
-          process.domain &&
-          listener.name !== 'domainUncaughtExceptionClear' &&
-          domainSet.has(process.domain)) {
+        process.domain &&
+        listener.name !== 'domainUncaughtExceptionClear' &&
+        domainSet.has(process.domain)) {
         // Throw an error so that the event will not be added and the current
         // domain takes over. That way the user is notified about the error
         // and the current code evaluation is stopped, just as any other code
@@ -363,8 +392,8 @@ function REPLServer(prompt,
   const savedRegExMatches = ['', '', '', '', '', '', '', '', '', ''];
   const sep = '\u0000\u0000\u0000';
   const regExMatcher = new RegExp(`^${sep}(.*)${sep}(.*)${sep}(.*)${sep}(.*)` +
-                                  `${sep}(.*)${sep}(.*)${sep}(.*)${sep}(.*)` +
-                                  `${sep}(.*)$`);
+    `${sep}(.*)${sep}(.*)${sep}(.*)${sep}(.*)` +
+    `${sep}(.*)$`);
 
   eval_ = eval_ || defaultEval;
 
@@ -417,7 +446,7 @@ function REPLServer(prompt,
     // an expression.  Note that if the above condition changes,
     // lib/internal/repl/utils.js needs to be changed to match.
     if (RegExpPrototypeExec(/^\s*{/, code) !== null &&
-        RegExpPrototypeExec(/;\s*$/, code) === null) {
+      RegExpPrototypeExec(/;\s*$/, code) === null) {
       code = `(${StringPrototypeTrim(code)})\n`;
       wrappedCmd = true;
     }
@@ -492,7 +521,7 @@ function REPLServer(prompt,
       while (true) {
         try {
           if (self.replMode === module.exports.REPL_MODE_STRICT &&
-              RegExpPrototypeExec(/^\s*$/, code) === null) {
+            RegExpPrototypeExec(/^\s*$/, code) === null) {
             // "void 0" keeps the repl from returning "use strict" as the result
             // value for statements and declarations that don't return a value.
             code = `'use strict'; void 0;\n${code}`;
@@ -684,7 +713,7 @@ function REPLServer(prompt,
               'module';
             if (StringPrototypeIncludes(e.message, importErrorStr)) {
               e.message = 'Cannot use import statement inside the Node.js ' +
-                'REPL, alternatively use dynamic import';
+                'REPL, alternatively use dynamic import: ' + toDynamicImport(self.lines.at(-1));
               e.stack = SideEffectFreeRegExpPrototypeSymbolReplace(
                 /SyntaxError:.*\n/,
                 e.stack,
@@ -712,7 +741,7 @@ function REPLServer(prompt,
     }
 
     if (options[kStandaloneREPL] &&
-        process.listenerCount('uncaughtException') !== 0) {
+      process.listenerCount('uncaughtException') !== 0) {
       process.nextTick(() => {
         process.emit('uncaughtException', e);
         self.clearBufferedCommand();
@@ -729,7 +758,7 @@ function REPLServer(prompt,
       errStack = '';
       ArrayPrototypeForEach(lines, (line) => {
         if (!matched &&
-            RegExpPrototypeExec(/^\[?([A-Z][a-z0-9_]*)*Error/, line) !== null) {
+          RegExpPrototypeExec(/^\[?([A-Z][a-z0-9_]*)*Error/, line) !== null) {
           errStack += writer.options.breakLength >= line.length ?
             `Uncaught ${line}` :
             `Uncaught:\n${line}`;
@@ -875,8 +904,8 @@ function REPLServer(prompt,
     // display next prompt and return.
     if (trimmedCmd) {
       if (StringPrototypeCharAt(trimmedCmd, 0) === '.' &&
-          StringPrototypeCharAt(trimmedCmd, 1) !== '.' &&
-          NumberIsNaN(NumberParseFloat(trimmedCmd))) {
+        StringPrototypeCharAt(trimmedCmd, 1) !== '.' &&
+        NumberIsNaN(NumberParseFloat(trimmedCmd))) {
         const matches = RegExpPrototypeExec(/^\.([^\s]+)\s*(.*)$/, trimmedCmd);
         const keyword = matches && matches[1];
         const rest = matches && matches[2];
@@ -901,10 +930,10 @@ function REPLServer(prompt,
       ReflectApply(_memory, self, [cmd]);
 
       if (e && !self[kBufferedCommandSymbol] &&
-          StringPrototypeStartsWith(StringPrototypeTrim(cmd), 'npm ')) {
+        StringPrototypeStartsWith(StringPrototypeTrim(cmd), 'npm ')) {
         self.output.write('npm should be run outside of the ' +
-                                'Node.js REPL, in your normal shell.\n' +
-                                '(Press Ctrl+D to exit.)\n');
+          'Node.js REPL, in your normal shell.\n' +
+          '(Press Ctrl+D to exit.)\n');
         self.displayPrompt();
         return;
       }
@@ -929,11 +958,11 @@ function REPLServer(prompt,
 
       // If we got any output - print it (if no error)
       if (!e &&
-          // When an invalid REPL command is used, error message is printed
-          // immediately. We don't have to print anything else. So, only when
-          // the second argument to this function is there, print it.
-          arguments.length === 2 &&
-          (!self.ignoreUndefined || ret !== undefined)) {
+        // When an invalid REPL command is used, error message is printed
+        // immediately. We don't have to print anything else. So, only when
+        // the second argument to this function is there, print it.
+        arguments.length === 2 &&
+        (!self.ignoreUndefined || ret !== undefined)) {
         if (!self.underscoreAssigned) {
           self.last = ret;
         }
@@ -984,7 +1013,7 @@ function REPLServer(prompt,
     if (!self.editorMode || !self.terminal) {
       // Before exiting, make sure to clear the line.
       if (key.ctrl && key.name === 'd' &&
-          self.cursor === 0 && self.line.length === 0) {
+        self.cursor === 0 && self.line.length === 0) {
         self.clearLine();
       }
       clearPreview(key);
@@ -1181,7 +1210,7 @@ const importRE = /\bimport\s*\(\s*['"`](([\w@./:-]+\/)?(?:[\w@./:-]*))(?![^'"`])
 const requireRE = /\brequire\s*\(\s*['"`](([\w@./:-]+\/)?(?:[\w@./:-]*))(?![^'"`])$/;
 const fsAutoCompleteRE = /fs(?:\.promises)?\.\s*[a-z][a-zA-Z]+\(\s*["'](.*)/;
 const simpleExpressionRE =
-    /(?:[\w$'"`[{(](?:\w|\$|['"`\]})])*\??\.)*[a-zA-Z_$](?:\w|\$)*\??\.?$/;
+  /(?:[\w$'"`[{(](?:\w|\$|['"`\]})])*\??\.)*[a-zA-Z_$](?:\w|\$)*\??\.?$/;
 const versionedFileNamesRe = /-\d+\.\d+/;
 
 function isIdentifier(str) {
@@ -1337,15 +1366,15 @@ function complete(line, callback) {
         const dirents = gracefulReaddir(dir, { withFileTypes: true }) || [];
         ArrayPrototypeForEach(dirents, (dirent) => {
           if (RegExpPrototypeExec(versionedFileNamesRe, dirent.name) !== null ||
-              dirent.name === '.npm') {
+            dirent.name === '.npm') {
             // Exclude versioned names that 'npm' installs.
             return;
           }
           const extension = path.extname(dirent.name);
           const base = StringPrototypeSlice(dirent.name, 0, -extension.length);
           if (!dirent.isDirectory()) {
             if (StringPrototypeIncludes(extensions, extension) &&
-                (!subdir || base !== 'index')) {
+              (!subdir || base !== 'index')) {
               ArrayPrototypePush(group, `${subdir}${base}`);
             }
             return;
@@ -1398,7 +1427,7 @@ function complete(line, callback) {
         ArrayPrototypeForEach(dirents, (dirent) => {
           const { name } = dirent;
           if (RegExpPrototypeExec(versionedFileNamesRe, name) !== null ||
-              name === '.npm') {
+            name === '.npm') {
             // Exclude versioned names that 'npm' installs.
             return;
           }
@@ -1431,20 +1460,20 @@ function complete(line, callback) {
 
     ArrayPrototypePush(completionGroups, _builtinLibs, nodeSchemeBuiltinLibs);
   } else if ((match = RegExpPrototypeExec(fsAutoCompleteRE, line)) !== null &&
-             this.allowBlockingCompletions) {
+    this.allowBlockingCompletions) {
     ({ 0: completionGroups, 1: completeOn } = completeFSFunctions(match));
-  // Handle variable member lookup.
-  // We support simple chained expressions like the following (no function
-  // calls, etc.). That is for simplicity and also because we *eval* that
-  // leading expression so for safety (see WARNING above) don't want to
-  // eval function calls.
-  //
-  //   foo.bar<|>     # completions for 'foo' with filter 'bar'
-  //   spam.eggs.<|>  # completions for 'spam.eggs' with filter ''
-  //   foo<|>         # all scope vars with filter 'foo'
-  //   foo.<|>        # completions for 'foo' with filter ''
+    // Handle variable member lookup.
+    // We support simple chained expressions like the following (no function
+    // calls, etc.). That is for simplicity and also because we *eval* that
+    // leading expression so for safety (see WARNING above) don't want to
+    // eval function calls.
+    //
+    //   foo.bar<|>     # completions for 'foo' with filter 'bar'
+    //   spam.eggs.<|>  # completions for 'spam.eggs' with filter ''
+    //   foo<|>         # all scope vars with filter 'foo'
+    //   foo.<|>        # completions for 'foo' with filter ''
   } else if (line.length === 0 ||
-             RegExpPrototypeExec(/\w|\.|\$/, line[line.length - 1]) !== null) {
+    RegExpPrototypeExec(/\w|\.|\$/, line[line.length - 1]) !== null) {
     const { 0: match } = RegExpPrototypeExec(simpleExpressionRE, line) || [''];
     if (line.length !== 0 && !match) {
       completionGroupsLoaded();
@@ -1495,7 +1524,7 @@ function complete(line, callback) {
       try {
         let p;
         if ((typeof obj === 'object' && obj !== null) ||
-            typeof obj === 'function') {
+          typeof obj === 'function') {
           memberGroups.push(filteredOwnPropertyNames(obj));
           p = ObjectGetPrototypeOf(obj);
         } else {

test/parallel/test-repl.js

@@ -818,7 +818,41 @@ const tcpTests = [
       kArrow,
       '',
       'Uncaught:',
-      /^SyntaxError: .* dynamic import/,
+      'SyntaxError: Cannot use import statement inside the Node.js REPL, \
+alternatively use dynamic import: const comeOn = await import(\'fhqwhgads\');',
+    ]
+  },
+  {
+    send: 'import { export1, export2 } from "module-name"',
+    expect: [
+      kSource,
+      kArrow,
+      '',
+      'Uncaught:',
+      'SyntaxError: Cannot use import statement inside the Node.js REPL, \
+alternatively use dynamic import: const {export1,export2} = await import(\'module-name\');',
+    ]
+  },
+  {
+    send: 'import * as name from "module-name";',
+    expect: [
+      kSource,
+      kArrow,
+      '',
+      'Uncaught:',
+      'SyntaxError: Cannot use import statement inside the Node.js REPL, \
+alternatively use dynamic import: const name = await import(\'module-name\');',
+    ]
+  },
+  {
+    send: 'import "module-name";',
+    expect: [
+      kSource,
+      kArrow,
+      '',
+      'Uncaught:',
+      'SyntaxError: Cannot use import statement inside the Node.js REPL, \
+alternatively use dynamic import: const moduleName = await import(\'module-name\');',
     ]
   },
 ];