@@ -5,6 +5,7 @@ npm-debug.log*
 yarn-debug.log*
 yarn-error.log*
 lerna-debug.log*
+out.js
 
 # Diagnostic reports (https://nodejs.org/api/report.html)
 report.[0-9]*.[0-9]*.[0-9]*.[0-9]*.json
 
@@ -0,0 +1,10 @@
+let esbuild = require('esbuild')
+esbuild
+  .build({
+    entryPoints: ['src/index.test.ts'],
+    bundle: true,
+    platform: 'browser',
+    format: 'iife',
+    outfile: 'out.js'
+  })
+  .catch(() => process.exit(1))
@@ -0,0 +1,19 @@
+module.exports = function (config) {
+  config.set({
+    plugins: ['karma-webpack', 'karma-jasmine', 'karma-chrome-launcher'],
+
+    // base path that will be used to resolve all patterns (eg. files, exclude)
+    basePath: '',
+
+    // frameworks to use
+    // available frameworks: https://npmjs.org/browse/keyword/karma-adapter
+    frameworks: ['jasmine'],
+
+    // list of files / patterns to load in the browser
+    // Here I'm including all of the the Jest tests which are all under the __tests__ directory.
+    // You may need to tweak this pattern to find your test files/
+    files: ['./karma-setup.js', 'out.js'],
+    browsers: ['ChromeHeadless'],
+    singleRun: true
+  })
+}
@@ -0,0 +1,14 @@
+// the jest.fn() API
+let jest = require('jest-mock')
+// The matchers API
+let expect = require('expect')
+
+// Add missing Jest functions
+window.test = window.it
+window.test.each = (inputs) => (testName, test) =>
+  inputs.forEach((args) => window.it(testName, () => test(...args)))
+window.test.todo = function () {
+  return undefined
+}
+window.jest = jest
+window.expect = expect