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

1 files changed, 31 insertions, 0 deletions

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)
+  })
+})