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, 64 insertions, 0 deletions

diff --git a/actioncable/karma.conf.js b/actioncable/karma.conf.js
new file mode 100644
index 0000000000..845b38d74f
--- /dev/null
+++ b/actioncable/karma.conf.js
@@ -0,0 +1,64 @@
+const config = {
+  browsers: ["ChromeHeadless"],
+  frameworks: ["qunit"],
+  files: [
+    "test/javascript/compiled/test.js",
+  ],
+
+  client: {
+    clearContext: false,
+    qunit: {
+      showUI: true
+    }
+  },
+
+  singleRun: true,
+  autoWatch: false,
+
+  captureTimeout: 180000,
+  browserDisconnectTimeout: 180000,
+  browserDisconnectTolerance: 3,
+  browserNoActivityTimeout: 300000,
+}
+
+if (process.env.CI) {
+  config.customLaunchers = {
+    sl_chrome: sauce("chrome", 70),
+    sl_ff: sauce("firefox", 63),
+    sl_safari: sauce("safari", 12.0, "macOS 10.13"),
+    sl_edge: sauce("microsoftedge", 17.17134, "Windows 10"),
+    sl_ie_11: sauce("internet explorer", 11, "Windows 8.1"),
+  }
+
+  config.browsers = Object.keys(config.customLaunchers)
+  config.reporters = ["dots", "saucelabs"]
+
+  config.sauceLabs = {
+    testName: "ActionCable JS Client",
+    retryLimit: 3,
+    build: buildId(),
+  }
+
+  function sauce(browserName, version, platform) {
+    const options = {
+      base: "SauceLabs",
+      browserName: browserName.toString(),
+      version: version.toString(),
+    }
+    if (platform) {
+      options.platform = platform.toString()
+    }
+    return options
+  }
+
+  function buildId() {
+    const { TRAVIS_BUILD_NUMBER, TRAVIS_BUILD_ID } = process.env
+    return TRAVIS_BUILD_NUMBER && TRAVIS_BUILD_ID
+      ? `TRAVIS #${TRAVIS_BUILD_NUMBER} (${TRAVIS_BUILD_ID})`
+      : ""
+  }
+}
+
+module.exports = function(karmaConfig) {
+  karmaConfig.set(config)
+}