Convert ActionCable tests from CoffeeScript to ES2015 and replace Blade with Karma and Rollup (#34440)

* Rename .coffee files in ActionCable test suite in prep for decaffeination

* Decaffeinate ActionCable tests

* Replace Blade with Karma and Rollup to run ActionCable JS tests

- Add karma and qunit devDependencies

- Add test script to ActionCable package

- Use rollup to bundle ActionCable tests

- Use karma as the ActionCable JS test runner

* Replace vendored mock-socket with package devDependency in ActionCable

* Move ActionCable yarn install to TravisCI before_install config

* Clean up decaffeinated ActionCable tests to use consistent formatting

14 files changed, 232 insertions, 181 deletions

diff --git a/actioncable/test/javascript/src/test.coffee b/actioncable/test/javascript/src/test.coffee
deleted file mode 100644
index eb95fb2604..0000000000
--- a/actioncable/test/javascript/src/test.coffee
+++ /dev/null
@@ -1,3 +0,0 @@
-#= require action_cable
-#= require ./test_helpers
-#= require_tree ./unit
diff --git a/actioncable/test/javascript/src/test.js b/actioncable/test/javascript/src/test.js
new file mode 100644
index 0000000000..1fca7ab4d3
--- /dev/null
+++ b/actioncable/test/javascript/src/test.js
@@ -0,0 +1,5 @@
+import "./test_helpers/index"
+import "./unit/action_cable_test"
+import "./unit/consumer_test"
+import "./unit/subscription_test"
+import "./unit/subscriptions_test"
diff --git a/actioncable/test/javascript/src/test_helpers/consumer_test_helper.coffee b/actioncable/test/javascript/src/test_helpers/consumer_test_helper.coffee
deleted file mode 100644
index a9e95c37f0..0000000000
--- a/actioncable/test/javascript/src/test_helpers/consumer_test_helper.coffee
+++ /dev/null
@@ -1,47 +0,0 @@
-#= require mock-socket
-
-{TestHelpers} = ActionCable
-
-TestHelpers.consumerTest = (name, options = {}, callback) ->
-  unless callback?
-    callback = options
-    options = {}
-
-  options.url ?= TestHelpers.testURL
-
-  QUnit.test name, (assert) ->
-    doneAsync = assert.async()
-
-    ActionCable.WebSocket = MockWebSocket
-    server = new MockServer options.url
-    consumer = ActionCable.createConsumer(options.url)
-
-    server.on "connection", ->
-      clients = server.clients()
-      assert.equal clients.length, 1
-      assert.equal clients[0].readyState, WebSocket.OPEN
-
-    server.broadcastTo = (subscription, data = {}, callback) ->
-      data.identifier = subscription.identifier
-
-      if data.message_type
-        data.type = ActionCable.INTERNAL.message_types[data.message_type]
-        delete data.message_type
-
-      server.send(JSON.stringify(data))
-      TestHelpers.defer(callback)
-
-    done = ->
-      consumer.disconnect()
-      server.close()
-      doneAsync()
-
-    testData = {assert, consumer, server, done}
-
-    if options.connect is false
-      callback(testData)
-    else
-      server.on "connection", ->
-        testData.client = server.clients()[0]
-        callback(testData)
-      consumer.connect()
diff --git a/actioncable/test/javascript/src/test_helpers/consumer_test_helper.js b/actioncable/test/javascript/src/test_helpers/consumer_test_helper.js
new file mode 100644
index 0000000000..f1abea331b
--- /dev/null
+++ b/actioncable/test/javascript/src/test_helpers/consumer_test_helper.js
@@ -0,0 +1,58 @@
+import { WebSocket as MockWebSocket, Server as MockServer } from "mock-socket"
+import ActionCable from "../../../../app/javascript/action_cable/index"
+import {defer, testURL} from "./index"
+
+export default function(name, options, callback) {
+  if (options == null) { options = {} }
+  if (callback == null) {
+    callback = options
+    options = {}
+  }
+
+  if (options.url == null) { options.url = testURL }
+
+  return QUnit.test(name, function(assert) {
+    const doneAsync = assert.async()
+
+    ActionCable.WebSocket = MockWebSocket
+    const server = new MockServer(options.url)
+    const consumer = ActionCable.createConsumer(options.url)
+
+    server.on("connection", function() {
+      const clients = server.clients()
+      assert.equal(clients.length, 1)
+      assert.equal(clients[0].readyState, WebSocket.OPEN)
+    })
+
+    server.broadcastTo = function(subscription, data, callback) {
+      if (data == null) { data = {} }
+      data.identifier = subscription.identifier
+
+      if (data.message_type) {
+        data.type = ActionCable.INTERNAL.message_types[data.message_type]
+        delete data.message_type
+      }
+
+      server.send(JSON.stringify(data))
+      defer(callback)
+    }
+
+    const done = function() {
+      consumer.disconnect()
+      server.close()
+      doneAsync()
+    }
+
+    const testData = {assert, consumer, server, done}
+
+    if (options.connect === false) {
+      callback(testData)
+    } else {
+      server.on("connection", function() {
+        testData.client = server.clients()[0]
+        callback(testData)
+      })
+      consumer.connect()
+    }
+  })
+}
diff --git a/actioncable/test/javascript/src/test_helpers/index.coffee b/actioncable/test/javascript/src/test_helpers/index.coffee
deleted file mode 100644
index c84cbbcb2c..0000000000
--- a/actioncable/test/javascript/src/test_helpers/index.coffee
+++ /dev/null
@@ -1,11 +0,0 @@
-#= require_self
-#= require_tree .
-
-ActionCable.TestHelpers =
-  testURL: "ws://cable.example.com/"
-
-  defer: (callback) ->
-    setTimeout(callback, 1)
-
-originalWebSocket = ActionCable.WebSocket
-QUnit.testDone -> ActionCable.WebSocket = originalWebSocket
diff --git a/actioncable/test/javascript/src/test_helpers/index.js b/actioncable/test/javascript/src/test_helpers/index.js
new file mode 100644
index 0000000000..5fa46c21ae
--- /dev/null
+++ b/actioncable/test/javascript/src/test_helpers/index.js
@@ -0,0 +1,10 @@
+import ActionCable from "../../../../app/javascript/action_cable/index"
+
+export const testURL = "ws://cable.example.com/"
+
+export function defer(callback) {
+  setTimeout(callback, 1)
+}
+
+const originalWebSocket = ActionCable.WebSocket
+QUnit.testDone(() => ActionCable.WebSocket = originalWebSocket)
diff --git a/actioncable/test/javascript/src/unit/action_cable_test.coffee b/actioncable/test/javascript/src/unit/action_cable_test.coffee
deleted file mode 100644
index 3944f3a7f6..0000000000
--- a/actioncable/test/javascript/src/unit/action_cable_test.coffee
+++ /dev/null
@@ -1,41 +0,0 @@
-{module, test} = QUnit
-{testURL} = ActionCable.TestHelpers
-
-module "ActionCable", ->
-  module "Adapters", ->
-    module "WebSocket", ->
-      test "default is window.WebSocket", (assert) ->
-        assert.equal ActionCable.WebSocket, window.WebSocket
-
-      test "configurable", (assert) ->
-        ActionCable.WebSocket = ""
-        assert.equal ActionCable.WebSocket, ""
-
-    module "logger", ->
-      test "default is window.console", (assert) ->
-        assert.equal ActionCable.logger, window.console
-
-      test "configurable", (assert) ->
-        ActionCable.logger = ""
-        assert.equal ActionCable.logger, ""
-
-  module "#createConsumer", ->
-    test "uses specified URL", (assert) ->
-      consumer = ActionCable.createConsumer(testURL)
-      assert.equal consumer.url, testURL
-
-    test "uses default URL", (assert) ->
-      pattern = ///#{ActionCable.INTERNAL.default_mount_path}$///
-      consumer = ActionCable.createConsumer()
-      assert.ok pattern.test(consumer.url), "Expected #{consumer.url} to match #{pattern}"
-
-    test "uses URL from meta tag", (assert) ->
-      element = document.createElement("meta")
-      element.setAttribute("name", "action-cable-url")
-      element.setAttribute("content", testURL)
-
-      document.head.appendChild(element)
-      consumer = ActionCable.createConsumer()
-      document.head.removeChild(element)
-
-      assert.equal consumer.url, testURL
diff --git a/actioncable/test/javascript/src/unit/action_cable_test.js b/actioncable/test/javascript/src/unit/action_cable_test.js
new file mode 100644
index 0000000000..8847d87545
--- /dev/null
+++ b/actioncable/test/javascript/src/unit/action_cable_test.js
@@ -0,0 +1,55 @@
+import ActionCable from "../../../../app/javascript/action_cable/index"
+import {testURL} from "../test_helpers/index"
+
+const {module, test} = QUnit
+
+module("ActionCable", () => {
+  module("Adapters", () => {
+    module("WebSocket", () => {
+      test("default is window.WebSocket", assert => {
+        assert.equal(ActionCable.WebSocket, window.WebSocket)
+      })
+
+      test("configurable", assert => {
+        ActionCable.WebSocket = ""
+        assert.equal(ActionCable.WebSocket, "")
+      })
+    })
+
+    module("logger", () => {
+      test("default is window.console", assert => {
+        assert.equal(ActionCable.logger, window.console)
+      })
+
+      test("configurable", assert => {
+        ActionCable.logger = ""
+        assert.equal(ActionCable.logger, "")
+      })
+    })
+  })
+
+  module("#createConsumer", () => {
+    test("uses specified URL", assert => {
+      const consumer = ActionCable.createConsumer(testURL)
+      assert.equal(consumer.url, testURL)
+    })
+
+    test("uses default URL", assert => {
+      const pattern = new RegExp(`${ActionCable.INTERNAL.default_mount_path}$`)
+      const consumer = ActionCable.createConsumer()
+      assert.ok(pattern.test(consumer.url), `Expected ${consumer.url} to match ${pattern}`)
+    })
+
+    test("uses URL from meta tag", assert => {
+      const element = document.createElement("meta")
+      element.setAttribute("name", "action-cable-url")
+      element.setAttribute("content", testURL)
+
+      document.head.appendChild(element)
+      const consumer = ActionCable.createConsumer()
+      document.head.removeChild(element)
+
+      assert.equal(consumer.url, testURL)
+    })
+  })
+})
diff --git a/actioncable/test/javascript/src/unit/consumer_test.coffee b/actioncable/test/javascript/src/unit/consumer_test.coffee
deleted file mode 100644
index 41445274eb..0000000000
--- a/actioncable/test/javascript/src/unit/consumer_test.coffee
+++ /dev/null
@@ -1,14 +0,0 @@
-{module, test} = QUnit
-{consumerTest} = ActionCable.TestHelpers
-
-module "ActionCable.Consumer", ->
-  consumerTest "#connect", connect: false, ({consumer, server, assert, done}) ->
-    server.on "connection", ->
-      assert.equal consumer.connect(), false
-      done()
-
-    consumer.connect()
-
-  consumerTest "#disconnect", ({consumer, client, done}) ->
-    client.addEventListener("close", done)
-    consumer.disconnect()
diff --git a/actioncable/test/javascript/src/unit/consumer_test.js b/actioncable/test/javascript/src/unit/consumer_test.js
new file mode 100644
index 0000000000..acc618bf0c
--- /dev/null
+++ b/actioncable/test/javascript/src/unit/consumer_test.js
@@ -0,0 +1,19 @@
+import consumerTest from "../test_helpers/consumer_test_helper"
+
+const {module} = QUnit
+
+module("ActionCable.Consumer", () => {
+  consumerTest("#connect", {connect: false}, ({consumer, server, assert, done}) => {
+    server.on("connection", () => {
+      assert.equal(consumer.connect(), false)
+      done()
+    })
+
+    consumer.connect()
+  })
+
+  consumerTest("#disconnect", ({consumer, client, done}) => {
+    client.addEventListener("close", done)
+    consumer.disconnect()
+  })
+})
diff --git a/actioncable/test/javascript/src/unit/subscription_test.coffee b/actioncable/test/javascript/src/unit/subscription_test.coffee
deleted file mode 100644
index 07027ed170..0000000000
--- a/actioncable/test/javascript/src/unit/subscription_test.coffee
+++ /dev/null
@@ -1,40 +0,0 @@
-{module, test} = QUnit
-{consumerTest} = ActionCable.TestHelpers
-
-module "ActionCable.Subscription", ->
-  consumerTest "#initialized callback", ({server, consumer, assert, done}) ->
-    consumer.subscriptions.create "chat",
-      initialized: ->
-        assert.ok true
-        done()
-
-  consumerTest "#connected callback", ({server, consumer, assert, done}) ->
-    subscription = consumer.subscriptions.create "chat",
-      connected: ->
-        assert.ok true
-        done()
-
-    server.broadcastTo(subscription, message_type: "confirmation")
-
-  consumerTest "#disconnected callback", ({server, consumer, assert, done}) ->
-    subscription = consumer.subscriptions.create "chat",
-      disconnected: ->
-        assert.ok true
-        done()
-
-    server.broadcastTo subscription, message_type: "confirmation", ->
-      server.close()
-
-  consumerTest "#perform", ({consumer, server, assert, done}) ->
-    subscription = consumer.subscriptions.create "chat",
-      connected: ->
-        @perform(publish: "hi")
-
-    server.on "message", (message) ->
-      data = JSON.parse(message)
-      assert.equal data.identifier, subscription.identifier
-      assert.equal data.command, "message"
-      assert.deepEqual data.data, JSON.stringify(action: { publish: "hi" })
-      done()
-
-    server.broadcastTo(subscription, message_type: "confirmation")
diff --git a/actioncable/test/javascript/src/unit/subscription_test.js b/actioncable/test/javascript/src/unit/subscription_test.js
new file mode 100644
index 0000000000..bf32e5f27d
--- /dev/null
+++ b/actioncable/test/javascript/src/unit/subscription_test.js
@@ -0,0 +1,54 @@
+import consumerTest from "../test_helpers/consumer_test_helper"
+
+const {module} = QUnit
+
+module("ActionCable.Subscription", () => {
+  consumerTest("#initialized callback", ({server, consumer, assert, done}) =>
+    consumer.subscriptions.create("chat", {
+      initialized() {
+        assert.ok(true)
+        done()
+      }
+    })
+  )
+
+  consumerTest("#connected callback", ({server, consumer, assert, done}) => {
+    const subscription = consumer.subscriptions.create("chat", {
+      connected() {
+        assert.ok(true)
+        done()
+      }
+    })
+
+    server.broadcastTo(subscription, {message_type: "confirmation"})
+  })
+
+  consumerTest("#disconnected callback", ({server, consumer, assert, done}) => {
+    const subscription = consumer.subscriptions.create("chat", {
+      disconnected() {
+        assert.ok(true)
+        done()
+      }
+    })
+
+    server.broadcastTo(subscription, {message_type: "confirmation"}, () => server.close())
+  })
+
+  consumerTest("#perform", ({consumer, server, assert, done}) => {
+    const subscription = consumer.subscriptions.create("chat", {
+      connected() {
+        this.perform({publish: "hi"})
+      }
+    })
+
+    server.on("message", (message) => {
+      const data = JSON.parse(message)
+      assert.equal(data.identifier, subscription.identifier)
+      assert.equal(data.command, "message")
+      assert.deepEqual(data.data, JSON.stringify({action: { publish: "hi" }}))
+      done()
+    })
+
+    server.broadcastTo(subscription, {message_type: "confirmation"})
+  })
+})
diff --git a/actioncable/test/javascript/src/unit/subscriptions_test.coffee b/actioncable/test/javascript/src/unit/subscriptions_test.coffee
deleted file mode 100644
index 170b370e4a..0000000000
--- a/actioncable/test/javascript/src/unit/subscriptions_test.coffee
+++ /dev/null
@@ -1,25 +0,0 @@
-{module, test} = QUnit
-{consumerTest} = ActionCable.TestHelpers
-
-module "ActionCable.Subscriptions", ->
-  consumerTest "create subscription with channel string", ({consumer, server, assert, done}) ->
-    channel = "chat"
-
-    server.on "message", (message) ->
-      data = JSON.parse(message)
-      assert.equal data.command, "subscribe"
-      assert.equal data.identifier, JSON.stringify({channel})
-      done()
-
-    consumer.subscriptions.create(channel)
-
-  consumerTest "create subscription with channel object", ({consumer, server, assert, done}) ->
-    channel = channel: "chat", room: "action"
-
-    server.on "message", (message) ->
-      data = JSON.parse(message)
-      assert.equal data.command, "subscribe"
-      assert.equal data.identifier, JSON.stringify(channel)
-      done()
-
-    consumer.subscriptions.create(channel)
diff --git a/actioncable/test/javascript/src/unit/subscriptions_test.js b/actioncable/test/javascript/src/unit/subscriptions_test.js
new file mode 100644
index 0000000000..33af5d4d82
--- /dev/null
+++ b/actioncable/test/javascript/src/unit/subscriptions_test.js
@@ -0,0 +1,31 @@
+import consumerTest from "../test_helpers/consumer_test_helper"
+
+const {module} = QUnit
+
+module("ActionCable.Subscriptions", () => {
+  consumerTest("create subscription with channel string", ({consumer, server, assert, done}) => {
+    const channel = "chat"
+
+    server.on("message", (message) => {
+      const data = JSON.parse(message)
+      assert.equal(data.command, "subscribe")
+      assert.equal(data.identifier, JSON.stringify({channel}))
+      done()
+    })
+
+    consumer.subscriptions.create(channel)
+  })
+
+  consumerTest("create subscription with channel object", ({consumer, server, assert, done}) => {
+    const channel = {channel: "chat", room: "action"}
+
+    server.on("message", (message) => {
+      const data = JSON.parse(message)
+      assert.equal(data.command, "subscribe")
+      assert.equal(data.identifier, JSON.stringify(channel))
+      done()
+    })
+
+    consumer.subscriptions.create(channel)
+  })
+})