feat: upgrade to babel 7 (#62)

Author: alexandernanberg

package.json

@@ -31,22 +31,21 @@
   "author": "Kent C. Dodds <kent@doddsfamily.us> (http://kentcdodds.com/)",
   "license": "MIT",
   "dependencies": {
+    "@babel/cli": "^7.0.0",
+    "@babel/core": "^7.0.0",
+    "@babel/plugin-proposal-class-properties": "^7.0.0",
+    "@babel/plugin-transform-modules-commonjs": "^7.0.0",
+    "@babel/preset-env": "^7.0.0",
+    "@babel/preset-react": "^7.0.0",
     "all-contributors-cli": "^5.0.0",
     "arrify": "^1.0.1",
-    "babel-cli": "^6.26.0",
-    "babel-core": "^6.26.3",
+    "babel-core": "^7.0.0-0",
     "babel-jest": "^23.4.2",
-    "babel-plugin-external-helpers": "^6.22.0",
     "babel-plugin-macros": "^2.3.0",
-    "babel-plugin-minify-dead-code-elimination": "^0.3.0",
+    "babel-plugin-minify-dead-code-elimination": "^0.4.0",
     "babel-plugin-module-resolver": "^3.1.1",
-    "babel-plugin-transform-class-properties": "^6.24.1",
-    "babel-plugin-transform-inline-environment-variables": "^0.3.0",
-    "babel-plugin-transform-object-rest-spread": "^6.26.0",
-    "babel-plugin-transform-react-jsx": "^6.24.1",
+    "babel-plugin-transform-inline-environment-variables": "^0.4.0",
     "babel-plugin-transform-react-remove-prop-types": "^0.4.13",
-    "babel-preset-env": "^1.6.1",
-    "babel-preset-react": "^6.24.1",
     "browserslist": "^4.0.0",
     "concurrently": "^3.5.1",
     "cross-env": "^5.1.4",
@@ -68,8 +67,8 @@
     "read-pkg-up": "^4.0.0",
     "resolve": "^1.6.0",
     "rimraf": "^2.6.2",
-    "rollup": "^0.63.0",
-    "rollup-plugin-babel": "^3.0.3",
+    "rollup": "^0.65.0",
+    "rollup-plugin-babel": "^4.0.0",
     "rollup-plugin-commonjs": "^9.1.0",
     "rollup-plugin-json": "^3.0.0",
     "rollup-plugin-node-builtins": "^2.1.2",

src/config/babelrc.js

@@ -27,41 +27,36 @@ const envTargets = isTest
     : {node: '4.5'}
 const envOptions = {modules: false, loose: true, targets: envTargets}
 
-module.exports = {
+module.exports = () => ({
   presets: [
-    [require.resolve('babel-preset-env'), envOptions],
-    ifAnyDep(['react', 'preact'], require.resolve('babel-preset-react')),
+    [require.resolve('@babel/preset-env'), envOptions],
+    ifAnyDep(
+      ['react', 'preact'],
+      [
+        require.resolve('@babel/preset-react'),
+        {pragma: isPreact ? 'React.h' : undefined},
+      ],
+    ),
   ].filter(Boolean),
   plugins: [
     require.resolve('babel-plugin-macros'),
-    isRollup ? require.resolve('babel-plugin-external-helpers') : null,
-    // we're actually not using JSX at all, but I'm leaving this
-    // in here just in case we ever do (this would be easy to miss).
     alias
       ? [
           require.resolve('babel-plugin-module-resolver'),
           {root: ['./src'], alias},
         ]
       : null,
-    isPreact
-      ? [
-          require.resolve('babel-plugin-transform-react-jsx'),
-          {pragma: 'React.h'},
-        ]
-      : null,
     [
       require.resolve('babel-plugin-transform-react-remove-prop-types'),
       isPreact ? {removeImport: true} : {mode: 'unsafe-wrap'},
     ],
     isUMD
       ? require.resolve('babel-plugin-transform-inline-environment-variables')
       : null,
-    // TODO: use loose mode when upgrading to babel@7
-    require.resolve('babel-plugin-transform-class-properties'),
-    require.resolve('babel-plugin-transform-object-rest-spread'),
+    [require.resolve('@babel/plugin-proposal-class-properties'), {loose: true}],
     require.resolve('babel-plugin-minify-dead-code-elimination'),
     treeshake
       ? null
-      : require.resolve('babel-plugin-transform-es2015-modules-commonjs'),
+      : require.resolve('@babel/plugin-transform-modules-commonjs'),
   ].filter(Boolean),
-}
+})

src/scripts/build/babel.js

@@ -26,7 +26,7 @@ if (!useSpecifiedOutDir && !args.includes('--no-clean')) {
 }
 
 const result = spawn.sync(
-  resolveBin('babel-cli', {executable: 'babel'}),
+  resolveBin('@babel/cli', {executable: 'babel'}),
   [...outDir, ...copyFiles, ...ignore, ...config, 'src'].concat(args),
   {stdio: 'inherit'},
 )