SyntaxError: Identifier 'module' has already been declared

[kolodziejczak-sz]

Simplified version of code that can reproduce this error:

// file.ts

const { builtinModules } from 'module';
export const foo = () => builtinModules ;

// build.js

const { builtinModules } = require('module');
const { buildSync } = require('esbuild');

buildSync({
    entryPoints: ['./file.ts'],
    write: true,
    outdir: distPath,
    minify: false,
    bundle: true,
    format: 'cjs',
    external: builtinModules,
});

node build.js ends up with following error:

const module = __toModule(require("module"));
^
SyntaxError: Identifier 'module' has already been declared
at wrapSafe (internal/modules/cjs/loader.js:1054:16)
at Module._compile (internal/modules/cjs/loader.js:1102:27)
at Object.Module._extensions..js (internal/modules/cjs/loader.js:1158:10)
at Module.load (internal/modules/cjs/loader.js:986:32)
at Function.Module._load (internal/modules/cjs/loader.js:879:14)
at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:71:12)
at internal/main/run_main_module.js:17:47

I guess "module" is restricted keyword when it comes to cjs format
node v12.18.0
esbuild v0.6.30,

[evanw]

I can't reproduce this. The code esbuild generates on my end is this:

const module2 = __toModule(require("module"));

Here's a live link to the code: https://repl.it/@EvanWallace/FlimsyDetailedSequences#index.js

[kolodziejczak-sz]

i created repo with code:
https://github.com/kolodziejczak-sz/esbuild-issue-reproduce
please clone and run npm start to reproduce error

[kolodziejczak-sz]

it's really about the line: "const module = require("module")" - "module" is reserved keyword when it comes to node execution
As you can see in the repo:
const { builinModules }= require("module");
is being transpiled to:
const module = __toModule(require("module"));

although i find it hard to explain why your repl doesn't have this problem

[evanw]

The fix was just released in version 0.6.33.