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'); ``` PR-URL: #48129 Reviewed-By: Antoine du Hamel <[email protected]>
nodejs · Aug 29, 2023 · 22c4a9b · 22c4a9b
1 parent 23721c2
commit 22c4a9b
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Showing 2 changed files with 95 additions and 2 deletions.
diff --git a/lib/repl.js b/lib/repl.js
@@ -43,6 +43,7 @@
 'use strict';
 
 const {
+  ArrayPrototypeAt,
   ArrayPrototypeFilter,
   ArrayPrototypeFindIndex,
   ArrayPrototypeForEach,
@@ -62,6 +63,7 @@ const {
   Boolean,
   Error,
   FunctionPrototypeBind,
+  JSONStringify,
   MathMaxApply,
   NumberIsNaN,
   NumberParseFloat,
@@ -105,7 +107,9 @@ 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,
@@ -225,6 +229,28 @@ 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 = '';
+  const ast = acornParse(codeLine, { __proto__: null, sourceType: 'module', ecmaVersion: 'latest' });
+  acornWalk.ancestor(ast, {
+    ImportDeclaration(node) {
+      const awaitDynamicImport = `await import(${JSONStringify(node.source.value)});`;
+      if (node.specifiers.length === 0) {
+        dynamicImportStatement += awaitDynamicImport;
+      } else if (node.specifiers.length === 1 && node.specifiers[0].type === 'ImportNamespaceSpecifier') {
+        dynamicImportStatement += `const ${node.specifiers[0].local.name} = ${awaitDynamicImport}`;
+      } else {
+        const importNames = ArrayPrototypeJoin(ArrayPrototypeMap(node.specifiers, ({ local, imported }) =>
+          (local.name === imported?.name ? local.name : `${imported?.name ?? 'default'}: ${local.name}`),
+        ), ', ');
+        dynamicImportStatement += `const { ${importNames} } = ${awaitDynamicImport}`;
+      }
+    },
+  });
+  return dynamicImportStatement;
+};
+
 function REPLServer(prompt,
                     stream,
                     eval_,
@@ -686,7 +712,7 @@ 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(ArrayPrototypeAt(self.lines, -1));
               e.stack = SideEffectFreeRegExpPrototypeSymbolReplace(
                 /SyntaxError:.*\n/,
                 e.stack,

diff --git a/test/parallel/test-repl.js b/test/parallel/test-repl.js
@@ -817,7 +817,74 @@ const tcpTests = [
       kArrow,
       '',
       'Uncaught:',
-      /^SyntaxError: .* dynamic import/,
+      'SyntaxError: Cannot use import statement inside the Node.js REPL, \
+alternatively use dynamic import: const { default: 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: await import("module-name");',
+    ]
+  },
+  {
+    send: 'import { export1 as localName1, export2 } from "bar";',
+    expect: [
+      kSource,
+      kArrow,
+      '',
+      'Uncaught:',
+      'SyntaxError: Cannot use import statement inside the Node.js REPL, \
+alternatively use dynamic import: const { export1: localName1, export2 } = await import("bar");',
+    ]
+  },
+  {
+    send: 'import alias from "bar";',
+    expect: [
+      kSource,
+      kArrow,
+      '',
+      'Uncaught:',
+      'SyntaxError: Cannot use import statement inside the Node.js REPL, \
+alternatively use dynamic import: const { default: alias } = await import("bar");',
+    ]
+  },
+  {
+    send: 'import alias, {namedExport} from "bar";',
+    expect: [
+      kSource,
+      kArrow,
+      '',
+      'Uncaught:',
+      'SyntaxError: Cannot use import statement inside the Node.js REPL, \
+alternatively use dynamic import: const { default: alias, namedExport } = await import("bar");',
     ]
   },
 ];