add test for regenerate message for shrinkwrap file

test/tap/shrinkwrap-empty-dep-value.js

@@ -0,0 +1,65 @@
+'use strict'
+
+const common = require('../common-tap.js')
+const path = require('path')
+const test = require('tap').test
+
+const Tacks = require('tacks')
+const File = Tacks.File
+const Dir = Tacks.Dir
+
+const basedir = common.pkg
+const testdir = path.join(basedir, 'testdir')
+
+const fixture = new Tacks(Dir({
+  cache: Dir(),
+  global: Dir(),
+  tmp: Dir(),
+  testdir: Dir({
+    'npm-shrinkwrap.json': File({
+      name: 'http-locks',
+      version: '0.0.0',
+      dependencies: {
+        minimist: {}
+      }
+    }),
+    'package.json': File({
+      name: 'http-locks',
+      version: '1.0.0',
+      dependencies: {
+        minimist: common.registry + '/minimist/-/minimist-0.0.5.tgz'
+      }
+    })
+  })
+}))
+
+function setup () {
+  cleanup()
+  fixture.create(basedir)
+}
+
+function cleanup () {
+  fixture.remove(basedir)
+}
+
+test('setup', function (t) {
+  setup()
+  t.done()
+})
+
+test('raises error to regenerate the shrinkwrap', function (t) {
+  common.npm(['install'], {cwd: testdir}, function (err, code, stdout, stderr) {
+    t.match(
+      stderr,
+      'npm ERR! If using a shrinkwrap, regenerate with "npm shrinkwrap".',
+      'returns message to regenerate shrinkwrap'
+    )
+
+    t.done()
+  })
+})
+
+test('cleanup', function (t) {
+  cleanup()
+  t.done()
+})