test for npm test

(obligatory 'yo dawg' reference)

lib/test.js

@@ -1,16 +1,11 @@
-/* eslint-disable standard/no-callback-literal */
-module.exports = test
-
 const testCmd = require('./utils/lifecycle-cmd.js')('test')
+const { completion, usage } = testCmd
+const cmd = (args, cb) => testCmd(args, er => {
+  if (er && er.code === 'ELIFECYCLE') {
+    cb('Test failed.  See above for more details.')
+  } else {
+    cb(er)
+  }
+})
 
-test.usage = testCmd.usage
-
-function test (args, cb) {
-  testCmd(args, function (er) {
-    if (!er) return cb()
-    if (er.code === 'ELIFECYCLE') {
-      return cb('Test failed.  See above for more details.')
-    }
-    return cb(er)
-  })
-}
+module.exports = Object.assign(cmd, { completion, usage })

test/lib/test.js

@@ -0,0 +1,40 @@
+const t = require('tap')
+const requireInject = require('require-inject')
+let RUN_ARGS = null
+const npmock = {
+  commands: {
+    run: (args, cb) => {
+      RUN_ARGS = args
+      cb()
+    }
+  }
+}
+const test = requireInject('../../lib/test.js', {
+  '../../lib/npm.js': npmock
+})
+
+t.test('run a test', t => {
+  test([], (er) => {
+    t.strictSame(RUN_ARGS, ['test'], 'added "test" to the args')
+  })
+  test(['hello', 'world'], (er) => {
+    t.strictSame(RUN_ARGS, ['test', 'hello', 'world'], 'added positional args')
+  })
+
+  const lcErr = Object.assign(new Error('should not see this'), {
+    code: 'ELIFECYCLE'
+  })
+  const otherErr = new Error('should see this')
+
+  npmock.commands.run = (args, cb) => cb(lcErr)
+  test([], (er) => {
+    t.equal(er, 'Test failed.  See above for more details.')
+  })
+
+  npmock.commands.run = (args, cb) => cb(otherErr)
+  test([], (er) => {
+    t.match(er, { message: 'should see this' })
+  })
+
+  t.end()
+})