fix: empty newline printed to stderr

Starting in v7.7.0 running `npm` (no args) is printing an empty newline
to stderr.

This fixes that by correctly exiting via errorHandler and avoiding
hitting the cb() never called error and adds a test to make sure we
avoid that regression moving forward.

Fixes: https://github.com/nodejs/node/pull/37678#issuecomment-808734374

Co-authored-by: Gar <gar+gh@danger.computer>

1 files changed, 14 insertions, 0 deletions

diff --git a/smoke-tests/index.js b/smoke-tests/index.js
index 38c3ed306..2c2a1b6ab 100644
--- a/smoke-tests/index.js
+++ b/smoke-tests/index.js
@@ -12,6 +12,7 @@ t.cleanSnapshot = s => s.split(cwd).join('{CWD}')
   .split(process.cwd()).join('{CWD}')
   .replace(/\\+/g, '/')
   .replace(/\r\n/g, '\n')
+  .replace(/\ \(in a browser\)/g, '')
 
 // setup server
 const registryServer = require('./server.js')
@@ -55,6 +56,19 @@ t.test('npm init', async t => {
   t.equal(pkg.version, '1.0.0', 'should have expected generated version')
 })
 
+t.test('npm (no args)', async t => {
+  const cmd = `"${process.execPath}" "${npmLocation}" --no-audit --no-update-notifier`
+  const cmdRes = await execAsync(cmd, { cwd: localPrefix, env })
+    .catch(err => {
+      t.equal(err.code, 1, 'should exit with error code')
+      return err
+    })
+
+  t.equal(cmdRes.stderr, '', 'should have no stderr output')
+  t.matchSnapshot(String(cmdRes.stdout),
+    'should have expected no args output')
+})
+
 t.test('npm install prodDep@version', async t => {
   const cmd = `${npmBin} install abbrev@1.0.4`
   const cmdRes = await exec(cmd)