Add ESM support

.travis.yml

@@ -1,5 +1,6 @@
 language: node_js
 node_js:
-  - "0.10"
-  - "4"
-  - "6"
+  - "10"
+  - "12"
+  - "13"
+  - "14"

example/esm-node/.gitignore

@@ -0,0 +1,7 @@
+/node_modules/*
+!/node_modules/.bin
+!/node_modules/teenytest
+/node_modules/.bin/*
+!/node_modules/.bin/teenytest
+
+

example/esm-node/lib/dog.js

@@ -0,0 +1,21 @@
+var _ = require('lodash')
+
+function Dog (name) {
+  this.name = name
+}
+
+Dog.prototype.bark = function (times) {
+  return _.map(_.range(times), function (i) {
+    return 'Woof #' + i
+  })
+}
+
+Dog.prototype.tag = function (side) {
+  if (side === 'front') {
+    return 'Hi, I am ' + this.name
+  } else {
+    return 'And here is my address'
+  }
+}
+
+module.exports = Dog

example/esm-node/package.json

@@ -0,0 +1,12 @@
+{
+  "name": "example",
+  "version": "1.0.0",
+  "private": true,
+  "description": "Just an example project",
+  "directories": {
+    "test": "test"
+  },
+  "scripts": {
+    "test": "teenytest"
+  }
+}

example/esm-node/supports-esm.js

@@ -0,0 +1,8 @@
+(async function () {
+  try {
+    await import('lodash')
+    process.exit(0)
+  } catch (err) {
+    process.exit(1)
+  }
+})()

example/esm-node/test/helper.js

@@ -0,0 +1,10 @@
+module.exports = {
+  beforeAll: function () { 'I run absolutely first' },
+  beforeEach: function () { 'I run before each test' },
+  afterEach: function () { 'I run right after each test' },
+  afterAll: function () { 'I run absolutely last' },
+  options: {
+    asyncTimeout: 100,
+    asyncInterval: 1
+  }
+}

example/esm-node/test/lib/dog-test.js

@@ -0,0 +1,24 @@
+var assert = require('core-assert')
+var Dog = require('../../lib/dog')
+
+module.exports = {
+  beforeEach: function () {
+    this.subject = new Dog('Sam')
+  },
+  bark: {
+    once: function () {
+      assert.deepEqual(this.subject.bark(1), ['Woof #0'])
+    },
+    twice: function () {
+      assert.deepEqual(this.subject.bark(2), ['Woof #0', 'Woof #1'])
+    }
+  },
+  tag: {
+    frontSaysName: function () {
+      assert.equal(this.subject.tag('front'), 'Hi, I am Sam')
+    },
+    backSaysAddress: function () {
+      assert.equal(this.subject.tag('back'), 'And here is my address')
+    }
+  }
+}

example/esm-node/test/lib/dog-test.mjs

@@ -0,0 +1,24 @@
+import assert from 'core-assert'
+import Dog from '../../lib/dog.js'
+
+export function beforeEach () {
+  this.subject = new Dog('Sam')
+};
+
+export const bark = {
+  once: function () {
+    assert.deepEqual(this.subject.bark(1), ['Woof #0'])
+  },
+  twice: function () {
+    assert.deepEqual(this.subject.bark(2), ['Woof #0', 'Woof #1'])
+  }
+}
+
+export const tag = {
+  frontSaysName: function () {
+    assert.equal(this.subject.tag('front'), 'Hi, I am Sam')
+  },
+  backSaysAddress: function () {
+    assert.equal(this.subject.tag('back'), 'And here is my address')
+  }
+}

example/esm-node/test/lib/single-function.js

@@ -0,0 +1,5 @@
+var assert = require('core-assert')
+
+module.exports = function blueIsRed () {
+  assert.equal('blue', 'red')
+}

index.js

@@ -6,7 +6,16 @@ var run = require('./lib/run')
 module.exports = function (testLocator, userOptions, cb) {
   if (arguments.length < 3) { cb = userOptions; userOptions = {} }
   var config = configure(testLocator, userOptions)
-  run(plan(prepare(config)), config, cb)
+  prepare(config)
+    .then(function (prepared) {
+      setImmediate(function () {
+        run(plan(prepared), config, cb)
+      })
+    }, function (er) {
+      setImmediate(function () {
+        cb(er)
+      })
+    })
 }
 
 module.exports.plugins = require('./lib/plugins/store')

lib/cli/argv-options.js

@@ -4,11 +4,11 @@ var minimist = require('minimist')
 module.exports = function () {
   var argv = minimist(process.argv.slice(2))
   return {
-    testLocator: _.isEmpty(argv['_']) ? undefined : _.castArray(argv['_']),
-    name: argv['name'],
-    helperPath: argv['helper'],
-    asyncTimeout: argv['timeout'],
-    configurator: argv['configurator'],
-    plugins: argv['plugin'] ? _.castArray(argv['plugin']) : undefined
+    testLocator: _.isEmpty(argv._) ? undefined : _.castArray(argv._),
+    name: argv.name,
+    helperPath: argv.helper,
+    asyncTimeout: argv.timeout,
+    configurator: argv.configurator,
+    plugins: argv.plugin ? _.castArray(argv.plugin) : undefined
   }
 }

lib/configure/defaults.js

@@ -2,7 +2,7 @@ module.exports = function () {
   return {
     cwd: process.cwd(),
     output: console.log,
-    testLocator: 'test/lib/**/*.js',
+    testLocator: 'test/lib/**/*.{js,mjs}',
     name: [],
     helperPath: 'test/helper.js',
     asyncTimeout: 5000,

lib/prepare/index.js

@@ -1,9 +1,10 @@
-var modules = require('./modules')
-var helper = require('./helper')
+var loadModules = require('./modules')
+var loadHelper = require('./helper')
 
-module.exports = function (config) {
-  return {
-    helper: helper(config.helperPath, config.cwd),
-    modules: modules(config.criteria, config.cwd)
-  }
+module.exports = async function (config) {
+  const [helper, modules] = await Promise.all([
+    loadHelper(config.helperPath, config.cwd),
+    loadModules(config.criteria, config.cwd)
+  ])
+  return { helper, modules }
 }

lib/prepare/modules/index.js

@@ -3,12 +3,13 @@ var filter = require('./filter')
 var compact = require('./compact')
 var _ = require('lodash')
 
-module.exports = function (criteria, cwd) {
-  return compact(_.compact(_.flatten(_.map(criteria.testFiles, function (fileCriteria) {
+module.exports = async function (criteria, cwd) {
+  const loadedFiles = await Promise.all(_.map(criteria.testFiles, async function (fileCriteria) {
     return filter(
-      load(fileCriteria.file, cwd),
+      await load(fileCriteria.file, cwd),
       fileCriteria,
       cwd
     )
-  }))))
+  }))
+  return compact(_.compact(_.flatten(loadedFiles)))
 }

lib/prepare/modules/load.js

@@ -5,13 +5,26 @@ var _ = require('lodash')
 function noOpHook () {}
 var HOOK_NAMES = ['beforeEach', 'beforeAll', 'afterEach', 'afterAll']
 
-module.exports = function (globPattern, cwd) {
-  return _.map(glob.sync(globPattern), function (file) {
+module.exports = async function (globPattern, cwd) {
+  return Promise.all(_.map(glob.sync(globPattern), async function (file) {
     var testPath = path.resolve(cwd, file)
-    var testModule = require(testPath)
+    var testModule
+    try {
+      testModule = require(testPath)
+    } catch (e) {
+      if (e.code !== 'ERR_REQUIRE_ESM') throw e
+      try {
+        testModule = await import(testPath)
+      } catch (err) {
+        if (err.message !== 'Not supported') throw err
+        const message = `You are trying to load test files that are ES modules (${testPath}), but ESM is not supported in this version of Node.js`
+        console.error(message)
+        throw new Error(message)
+      }
+    }
 
     return buildExampleGroup(testPath, testModule, file, [{ name: 'global' }])
-  })
+  }))
 }
 
 function buildExampleGroup (name, groupDeclaration, file, ancestors) {