Change localhost port for cypress tests and document how its used

CONTRIBUTING.md

@@ -2,22 +2,24 @@
 
 You will need:
 
-- Node.js and npm
-- webpack
+- [Yarn](https://yarnpkg.com/)
+- [Webpack](https://webpack.js.org/)
 
 Windows users will need additional setup to enable build capabilities in NPM.
 From an administrative command window:
 
-    npm install --global --production windows-build-tools
+```sh
+    yarn global add windows-build-tools
+```
 
 ## Getting started
 
 1. Fork the project
 2. Clone your forked project by running `git clone git@github.com:{
    YOUR_USERNAME }/shepherd.git`
-3. Run `npm install` to install node modules
+3. Run `yarn` to install node modules
 4. Test that you can build the source by moving/renaming the existing `dist`
-   directory and running `npm run build`
+   directory and running `yarn build`
 5. Assuming everything went well, you should now have a `dist` directory that
    matches the one you moved in step 4
 
@@ -28,16 +30,27 @@ you can focus on writing relevant code. If there is a fix or feature you would l
 to contribute, we ask that you take the following steps:
 
 1. Most of the _editable_ code lives in the `src` directory while built code
-   will end up in the `dist` directory upon running `npm run build`.
+   will end up in the `dist` directory upon running `yarn build`.
 
-2. Provide a thoughtful commit message and push your changes to your fork using
+2. The demo app is served out of the `docs/welcome` directory. Running `yarn start` will open it in your browser and initiate a live-reloading session as you make changes.
+
+
+## Opening Pull Requests
+
+1. Please Provide a thoughtful commit message and push your changes to your fork using
    `git push origin master` (assuming your forked project is using `origin` for
    the remote name and you are on the `master` branch).
 
-3. Open a Pull Request on GitHub with a description of your changes.
+2. Open a Pull Request on GitHub with a description of your changes.
 
 
 ## Testing
 
 All PRs, that change code functionality, are required to have accompanying tests.
 
+### Acceptance Tests
+
+Acceptance tests are run using [`cypress`](https://github.com/cypress-io/cypress). A number of different testing configurations can be found in [`package.json`](/package.json), but you can simply run `yarn test:ci:watch` to build your latest changes and begin running the tests inside a Chrome browser instance.
+
+⚠️ The acceptance tests are set up to run on `localhost` port `9002`. If you'd like to change this port, make sure to change the `baseUrl` option inside of [`cypress.json`](/cypress.json), and change any references to port `9002` in [`package.json`](/package.json) accordingly.
+

cypress.json

@@ -4,5 +4,6 @@
   "integrationFolder": "test/cypress/integration",
   "pluginsFile": "test/cypress/plugins/index.js",
   "supportFile": "test/cypress/support/index.js",
-  "video": false
+  "video": false,
+  "baseUrl": "http://localhost:9002"
 }

package.json

@@ -33,12 +33,12 @@
     "posttest:ci": "nyc report --reporter=lcov --reporter=text",
     "rewrite-paths": "replace 'SF:.*src' 'SF:src' coverage/lcov.info",
     "start": "yarn watch",
-    "start-test-server": "http-server",
+    "start-test-server": "http-server -p 9002",
     "test": "yarn test:ci",
     "test:build": "cross-env NODE_ENV=test yarn build",
     "test:ci": "yarn test:unit:ci && yarn test:cy:ci",
-    "test:cy:ci": "yarn test:build && start-server-and-test start-test-server http://localhost:8080 cy:run",
-    "test:cy:watch": "start-server-and-test start-test-server http://localhost:8080 cy:open",
+    "test:cy:ci": "yarn test:build && start-server-and-test start-test-server http://localhost:9002 cy:run",
+    "test:cy:watch": "yarn test:build && start-server-and-test start-test-server http://localhost:9002 cy:open",
     "test:unit:ci": "cross-env NODE_ENV=test webpack --config webpack.test.config.js && yarn mocha-headless-chrome",
     "test:unit:watch": "webpack-dev-server --config webpack.test.config.js",
     "watch": "yarn clean && webpack --watch --mode development"

test/cypress/integration/test.acceptance.js

@@ -7,7 +7,7 @@ describe('Shepherd Acceptance Tests', () => {
   beforeEach(() => {
     Shepherd = null;
 
-    cy.visit('http://localhost:8080/test/dummy/', {
+    cy.visit('/test/dummy/', {
       onLoad(contentWindow) {
         if (contentWindow.Shepherd) {
           return Shepherd = contentWindow.Shepherd;