Add jest and sample unit test

.eslintrc.json

@@ -1,11 +1,18 @@
 {
   "env": {
     "browser": true,
+    "jest/globals": true,
     "webextensions": true
   },
   "extends": [ "standard", "standard-react" ],
   "parser": "babel-eslint",
+  "plugins": [ "jest" ],
   "rules": {
+    "jest/no-disabled-tests": "warn",
+    "jest/no-focused-tests": "error",
+    "jest/no-identical-title": "error",
+    "jest/prefer-to-have-length": "warn",
+    "jest/valid-expect": "error",
     "semi": [ "error", "always" ]
   }
 }

.gitignore

@@ -21,4 +21,4 @@ yarn.lock
 
 npm-debug.log*
 yarn-debug.log*
-yarn-error.log*
+yarn-error.log*

__mocks__/fileMock.js

@@ -0,0 +1 @@
+module.exports = 'test-file-stub';

jest.config.js

@@ -0,0 +1,185 @@
+// For a detailed explanation regarding each configuration property, visit:
+// https://jestjs.io/docs/en/configuration.html
+
+module.exports = {
+  // All imported modules in your tests should be mocked automatically
+  // automock: false,
+
+  // Stop running tests after the first failure
+  // bail: false,
+
+  // Respect "browser" field in package.json when resolving modules
+  // browser: false,
+
+  // The directory where Jest should store its cached dependency information
+  // cacheDirectory: null,
+
+  // Automatically clear mock calls and instances between every test
+  clearMocks: true,
+
+  // Indicates whether the coverage information should be collected while executing the test
+  collectCoverage: true,
+
+  // An array of glob patterns indicating a set of files for which coverage information should be collected
+  collectCoverageFrom: [
+    '<rootDir>/**/*.js'
+  ],
+
+  // The directory where Jest should output its coverage files
+  coverageDirectory: 'coverage',
+
+  // An array of regexp pattern strings used to skip coverage collection
+  coveragePathIgnorePatterns: [
+    '\\\\node_modules\\\\'
+  ],
+
+  // A list of reporter names that Jest uses when writing coverage reports
+  coverageReporters: [
+    'json',
+    'text',
+    'lcov',
+    'clover'
+  ],
+
+  // An object that configures minimum threshold enforcement for coverage results
+  // coverageThreshold: null,
+
+  // Make calling deprecated APIs throw helpful error messages
+  // errorOnDeprecated: false,
+
+  // Force coverage collection from ignored files using a array of glob patterns
+  // forceCoverageMatch: [],
+
+  // A path to a module which exports an async function that is triggered once before all test suites
+  // globalSetup: null,
+
+  // A path to a module which exports an async function that is triggered once after all test suites
+  // globalTeardown: null,
+
+  // A set of global variables that need to be available in all test environments
+  globals: {},
+
+  // An array of directory names to be searched recursively up from the requiring module's location
+  // moduleDirectories: [
+  //   "node_modules"
+  // ],
+
+  // An array of file extensions your modules use
+  // moduleFileExtensions: [
+  //   "js",
+  //   "json",
+  //   "jsx",
+  //   "node"
+  // ],
+
+  // A map from regular expressions to module names that allow to stub out resources with a single module
+  moduleNameMapper: {
+    '\\.(jpg|jpeg|png|gif|eot|otf|webp|svg|ttf|woff|woff2|mp4|webm|wav|mp3|m4a|aac|oga)$': '<rootDir>/__mocks__/fileMock.js',
+    '\\.(css|less)$': 'identity-obj-proxy'
+  },
+
+  // An array of regexp pattern strings, matched against all module paths before considered 'visible' to the module loader
+  // modulePathIgnorePatterns: [],
+
+  // Activates notifications for test results
+  // notify: false,
+
+  // An enum that specifies notification mode. Requires { notify: true }
+  // notifyMode: "always",
+
+  // A preset that is used as a base for Jest's configuration
+  // preset: null,
+
+  // Run tests from one or more projects
+  // projects: null,
+
+  // Use this configuration option to add custom reporters to Jest
+  // reporters: undefined,
+
+  // Automatically reset mock state between every test
+  // resetMocks: false,
+
+  // Reset the module registry before running each individual test
+  // resetModules: false,
+
+  // A path to a custom resolver
+  // resolver: null,
+
+  // Automatically restore mock state between every test
+  // restoreMocks: false,
+
+  // The root directory that Jest should scan for tests and modules within
+  // rootDir: null,
+
+  // A list of paths to directories that Jest should use to search for files in
+  roots: [
+    '<rootDir>/src'
+  ],
+
+  // Allows you to use a custom runner instead of Jest's default test runner
+  // runner: "jest-runner",
+
+  // The paths to modules that run some code to configure or set up the testing environment before each test
+  // setupFiles: [],
+
+  // The path to a module that runs some code to configure or set up the testing framework before each test
+  // setupTestFrameworkScriptFile: null,
+
+  // A list of paths to snapshot serializer modules Jest should use for snapshot testing
+  // snapshotSerializers: [],
+
+  // The test environment that will be used for testing
+  // testEnvironment: "jest-environment-jsdom",
+
+  // Options that will be passed to the testEnvironment
+  // testEnvironmentOptions: {},
+
+  // Adds a location field to test results
+  // testLocationInResults: false,
+
+  // The glob patterns Jest uses to detect test files
+  testMatch: [
+    '**/__tests__/**/*.js?(x)',
+    '**/?(*.)+(spec|test).js?(x)'
+  ],
+
+  // An array of regexp pattern strings that are matched against all test paths, matched tests are skipped
+  testPathIgnorePatterns: [
+    '\\\\node_modules\\\\'
+  ],
+
+  // The regexp pattern Jest uses to detect test files
+  // testRegex: "",
+
+  // This option allows the use of a custom results processor
+  // testResultsProcessor: null,
+
+  // This option allows use of a custom test runner
+  // testRunner: "jasmine2",
+
+  // This option sets the URL for the jsdom environment. It is reflected in properties such as location.href
+  // testURL: "http://localhost",
+
+  // Setting this value to "fake" allows the use of fake timers for functions such as "setTimeout"
+  // timers: "real",
+
+  // A map from regular expressions to paths to transformers
+  // transform: null,
+
+  // An array of regexp pattern strings that are matched against all source file paths, matched files will skip transformation
+  transformIgnorePatterns: [
+    '\\\\node_modules\\\\'
+  ]
+
+  // An array of regexp pattern strings that are matched against all modules before the module loader will automatically return a mock for them
+  // unmockedModulePathPatterns: undefined,
+
+  // Indicates whether each individual test should be reported during the run
+  // verbose: null,
+
+  // An array of regexp patterns that are matched against all source file paths before re-running tests in watch mode
+  // watchPathIgnorePatterns: [],
+
+  // Whether to use watchman for file crawling
+  // watchman: true,
+};

package.json

@@ -12,10 +12,12 @@
   },
   "devDependencies": {
     "@babel/cli": "^7.1.0",
-    "@babel/core": "^7.1.0",
+    "@babel/core": "^7.2.2",
     "@babel/preset-env": "^7.1.0",
     "@babel/preset-react": "^7.0.0",
+    "babel-core": "^7.0.0-bridge.0",
     "babel-eslint": "^10.0.1",
+    "babel-jest": "^23.6.0",
     "babel-loader": "^8.0.2",
     "clean-webpack-plugin": "^1.0.0",
     "copy-webpack-plugin": "^4.6.0",
@@ -24,13 +26,17 @@
     "eslint-config-standard": "^12.0.0",
     "eslint-config-standard-react": "^7.0.2",
     "eslint-plugin-import": "^2.14.0",
+    "eslint-plugin-jest": "^22.1.3",
     "eslint-plugin-node": "^8.0.1",
     "eslint-plugin-promise": "^4.0.1",
     "eslint-plugin-react": "^7.12.3",
     "eslint-plugin-standard": "^4.0.0",
     "file-loader": "^3.0.1",
     "html-webpack-plugin": "^3.2.0",
+    "identity-obj-proxy": "^3.0.0",
+    "jest": "^23.6.0",
     "prop-types": "^15.6.2",
+    "regenerator-runtime": "^0.13.1",
     "style-loader": "^0.23.0",
     "stylelint": "^9.10.1",
     "stylelint-config-standard": "^18.2.0",
@@ -41,7 +47,8 @@
     "build": "webpack --config ./webpack.config.js --mode development",
     "lint": "npm run lint:css && npm run lint:js",
     "lint:css": "stylelint \"./src/devpanel/**/*.css\"",
-    "lint:js": "eslint ./src"
+    "lint:js": "eslint ./src",
+    "test": "jest"
   },
   "repository": {
     "type": "git",

src/devpanel/components/Footer/Footer.test.js

@@ -0,0 +1,7 @@
+import Footer from './Footer';
+
+describe('Footer.js', () => {
+  it('should render the footer', () => {
+    expect(Footer()).toMatchSnapshot();
+  });
+});

src/devpanel/components/Footer/__snapshots__/Footer.test.js.snap

@@ -0,0 +1,20 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`Footer.js should render the footer 1`] = `
+<footer
+  className="Footer"
+>
+  <a
+    href="https://github.com/Microsoft/Mezzurite-DevTools"
+    target="_blank"
+  >
+    <img
+      id="gh-logo"
+      src="test-file-stub"
+    />
+  </a>
+  <span>
+    Visit us on GitHub! ~ The Mezzurite Development Team
+  </span>
+</footer>
+`;