Upgrade to Relay 3.0.0

.babelrc.js

@@ -0,0 +1,23 @@
+module.exports = {
+  sourceMaps: "inline",
+  plugins: [
+    "babel-plugin-relay",
+    "./assert-messages-plugin.js",
+    "@atom/babel-plugin-chai-assert-async",
+    "@babel/plugin-proposal-class-properties",
+
+    // Needed for esprima
+    "@babel/plugin-proposal-object-rest-spread",
+  ],
+  presets: [
+    ["@babel/preset-env", {
+      targets: {electron: process.versions.electron}
+    }],
+    "@babel/preset-react"
+  ],
+  env: {
+    coverage: {
+      plugins: ["babel-plugin-istanbul"]
+    }
+  }
+}

CONTRIBUTING.md

@@ -162,7 +162,7 @@ We use the following technologies:
 * We interact with GitHub via its [GraphQL](https://graphql.org/) API.
 * [Relay](https://github.com/facebook/relay) is a layer of glue between React and GraphQL queries that handles responsibilities like query composition and caching.
 * Our tests are written with [Mocha](https://mochajs.org/) and [Chai](https://www.chaijs.com/) [_(with the "assert" style)_](https://www.chaijs.com/api/assert/). We also use [Enzyme](https://airbnb.io/enzyme/) to assert against React behavior.
-* We use a [custom Babel 6 transpiler pipeline](https://github.com/atom/atom-babel6-transpiler) to write modern source with JSX, `import` statements, and other constructs unavailable natively within Atom's Node.js version.
+* We use a [custom Babel 7 transpiler pipeline](https://github.com/atom/atom-babel7-transpiler) to write modern source with JSX, `import` statements, and other constructs unavailable natively within Atom's Node.js version.
 
 ### Updating the GraphQL Schema
 

assert-messages-plugin.js

@@ -1,4 +1,4 @@
-const generate = require('babel-generator').default;
+const generate = require('@babel/generator').default;
 
 module.exports = function({types: t}) {
   return {