child_process: empty options.env results in ENOMEM error

[ilikesleeping]

• Version: v10.16.1
• Platform: Windows 10 x64 Version 1803 (OS Build 17134.885)
• Subsystem: child_process

When calling another process, the exec and execSync commands fail with a ENOMEM error when using an empty object for the options.env variable. Using any non-undefined value at all in the env object makes the call work again.

const { execSync } = require('child_process');
execSync('node', {env: {}}) // Fails with ENOMEM error
execSync('node', {env: {x: undefined}}) // Fails with ENOMEM error
execSync('node', {env: {x: 0}}) // Works

The error trace:

Thrown:
{ Error: spawnSync C:\WINDOWS\system32\cmd.exe ENOMEM
    at Object.spawnSync (internal/child_process.js:1002:20)
    at spawnSync (child_process.js:614:24)
    at execSync (child_process.js:661:13)
  errno: 'ENOMEM',
  code: 'ENOMEM',
  syscall: 'spawnSync C:\\WINDOWS\\system32\\cmd.exe',
  path: 'C:\\WINDOWS\\system32\\cmd.exe',
  spawnargs: [ '/d', '/s', '/c', '"node"' ],
  error: [Circular],
  status: null,
  signal: null,
  output: null,
  pid: 0,
  stdout: null,
  stderr: null }

This did not happen in v10.15.*, and seems to affect v10.16.0 as well.

[addaleax]

@nodejs/platform-windows

[targos]

I confirm the behavior on Windows, with v12.7.0

[bnoordhuis]

libuv/libuv#2408 should fix that.

[richardlau]

Reopening until the libuv update lands.