install-test: fix shrinkwrap handling of package-lock.json (#20358)

For a simple project with .npmrc containing 'package-lock=false',
`npm install-test` command will generate package-lock.json.*.

If there is an existing package-lock.json, npm install-test triggers
lifecycle actions twice for both install and test.

PR-URL: npm/npm#20358
Credit: @raymondfeng
Reviewed-By: @zkat

lib/install/save.js

@@ -46,7 +46,7 @@ exports.saveShrinkwrap = saveShrinkwrap
 function saveShrinkwrap (tree, next) {
   validate('OF', arguments)
   if (!npm.config.get('shrinkwrap') || !npm.config.get('package-lock')) {
-    next()
+    return next()
   }
   createShrinkwrap(tree, {silent: false}, next)
 }

test/tap/install-test-cli-without-package-lock.js

@@ -0,0 +1,83 @@
+var fs = require('graceful-fs')
+var path = require('path')
+
+var mkdirp = require('mkdirp')
+var osenv = require('osenv')
+var rimraf = require('rimraf')
+var test = require('tap').test
+
+var common = require('../common-tap.js')
+
+var pkg = path.join(__dirname, path.basename(__filename, '.js'))
+
+var EXEC_OPTS = { cwd: pkg }
+
+var json = {
+  name: 'install-test-cli-without-package-lock',
+  description: 'fixture',
+  version: '0.0.0',
+  dependencies: {
+    dependency: 'file:./dependency'
+  }
+}
+
+var dependency = {
+  name: 'dependency',
+  description: 'fixture',
+  version: '0.0.0'
+}
+
+test('setup', function (t) {
+  setup()
+  t.pass('setup ran')
+  t.end()
+})
+
+test('\'npm install-test\' should not generate package-lock.json.*', function (t) {
+  common.npm(['install-test'], EXEC_OPTS, function (err, code, stderr, stdout) {
+    if (err) throw err
+    t.comment(stdout.trim())
+    t.comment(stderr.trim())
+    t.is(code, 0, 'npm install did not raise error code')
+    var files = fs.readdirSync(pkg).filter(function (f) {
+      return f.indexOf('package-lock.json.') === 0
+    })
+    t.notOk(
+      files.length > 0,
+      'package-lock.json.* should not be generated: ' + files
+    )
+    t.end()
+  })
+})
+
+test('cleanup', function (t) {
+  cleanup()
+  t.pass('cleaned up')
+  t.end()
+})
+
+function setup () {
+  mkdirp.sync(path.join(pkg, 'dependency'))
+  fs.writeFileSync(
+    path.join(pkg, 'dependency', 'package.json'),
+    JSON.stringify(dependency, null, 2)
+  )
+
+  mkdirp.sync(path.join(pkg, 'node_modules'))
+  fs.writeFileSync(
+    path.join(pkg, 'package.json'),
+    JSON.stringify(json, null, 2)
+  )
+
+  // Disable package-lock
+  fs.writeFileSync(
+    path.join(pkg, '.npmrc'),
+    'package-lock=false\n'
+  )
+  process.chdir(pkg)
+}
+
+function cleanup () {
+  process.chdir(osenv.tmpdir())
+  rimraf.sync(pkg)
+}