chore: Add npm command for running the multi-tab tests with the required dev server running

Author: jcoglan

bin/test-multitab.js

@@ -0,0 +1,14 @@
+'use strict';
+
+const { spawn } = require('child_process');
+const devserver = require('./dev-server');
+
+const MOCHA_BIN = './node_modules/.bin/mocha';
+const MULTITAB_TESTS = 'tests/multitab';
+const TIMEOUT = '10000'
+
+devserver.start(() => {
+  let argv = ['-t', TIMEOUT, MULTITAB_TESTS];
+  let mocha = spawn(MOCHA_BIN, argv, { stdio: 'inherit' });
+  mocha.on('close', (status) => process.exit(status));
+});

package.json

@@ -13,6 +13,7 @@
     "test-component": "mocha --exit tests/component # --exit for #8839",
     "test-fuzzy": "TYPE=fuzzy npm run test",
     "test-browser": "node ./bin/test-browser.js",
+    "test-multitab": "node ./bin/test-multitab.js",
     "test-memleak": "mocha -gc tests/memleak",
     "eslint": "eslint --cache bin/ packages/node_modules/**/src tests/",
     "dev": "./bin/run-dev.sh",