fix(gatsby-cypress): Run files through babel (#12400)

* Move files, add babel transform

* Add node env note in README

packages/gatsby-cypress/.babelrc

@@ -0,0 +1,5 @@
+{
+  "presets": [
+    ["babel-preset-gatsby-package"]
+  ]
+}

packages/gatsby-cypress/.gitignore

@@ -0,0 +1 @@
+/*.js

packages/gatsby-cypress/.npmignore

@@ -0,0 +1,34 @@
+# Logs
+logs
+*.log
+
+# Runtime data
+pids
+*.pid
+*.seed
+
+# Directory for instrumented libs generated by jscoverage/JSCover
+lib-cov
+
+# Coverage directory used by tools like istanbul
+coverage
+
+# Grunt intermediate storage (http://gruntjs.com/creating-plugins#storing-task-files)
+.grunt
+
+# node-waf configuration
+.lock-wscript
+
+# Compiled binary addons (http://nodejs.org/api/addons.html)
+build/Release
+
+# Dependency directory
+# https://www.npmjs.org/doc/misc/npm-faq.html#should-i-check-my-node_modules-folder-into-git
+node_modules
+*.un~
+yarn.lock
+src
+flow-typed
+coverage
+decls
+examples

packages/gatsby-cypress/README.md

@@ -8,6 +8,12 @@ as follows:
 import "gatsby-cypress/commands"
 ```
 
+You also need to expose a `CYPRESS_SUPPORT` environment variable to entirely eliminate any code relating to Cypress in the normal browser build. You can place it in your test script for example:
+
+```
+"test": "CYPRESS_SUPPORT=y npm run build && npm run start-server-and-test"
+```
+
 Once imported, the following additional commands are available:
 
 - `cy.getTestElement(selector)`: Selects elements where the `data-testid`

packages/gatsby-cypress/package.json

@@ -9,6 +9,15 @@
   "bugs": {
     "url": "https://github.com/gatsbyjs/gatsby/issues"
   },
+  "dependencies": {
+    "@babel/runtime": "^7.0.0"
+  },
+  "devDependencies": {
+    "@babel/cli": "^7.0.0",
+    "@babel/core": "^7.0.0",
+    "babel-preset-gatsby-package": "^0.1.3",
+    "cross-env": "^5.1.4"
+  },
   "keywords": [
     "gatsby",
     "cypress",
@@ -19,5 +28,10 @@
     "cypress": "^3.1.0",
     "gatsby": "^2.0.0-rc.13"
   },
-  "readme": "README.md"
+  "readme": "README.md",
+  "scripts": {
+    "build": "babel src --out-dir . --ignore **/__tests__",
+    "prepare": "cross-env NODE_ENV=production npm run build",
+    "watch": "babel -w src --out-dir . --ignore **/__tests__"
+  }
 }