Add do expressions proposal plugin

CHANGELOG.md

@@ -1,6 +1,8 @@
 # Change log
 
 ## [Unreleased]
+### Added
+  * Added "do expressions" proposal plugin.
 
 ## 3.0.0 - 2018-11-26
 

index.js

@@ -5,6 +5,7 @@
  * [Proposals]
  * https://babeljs.io/docs/en/babel-plugin-syntax-dynamic-import
  * https://babeljs.io/docs/en/babel-plugin-proposal-class-properties
+ * https://babeljs.io/docs/en/babel-plugin-proposal-do-expressions
  * https://babeljs.io/docs/en/babel-plugin-proposal-decorators
  *
  * [React]
@@ -44,6 +45,7 @@ module.exports = (context, options) => {
   let plugins = [
     '@babel/plugin-syntax-dynamic-import',
     '@babel/plugin-proposal-class-properties',
+    '@babel/plugin-proposal-do-expressions',
     ['@babel/plugin-proposal-decorators', { legacy: true }],
     ['@babel/plugin-transform-runtime', runtimeOpts],
   ];

package.json

@@ -30,6 +30,7 @@
   "dependencies": {
     "@babel/plugin-proposal-class-properties": "^7.1.0",
     "@babel/plugin-proposal-decorators": "^7.1.6",
+    "@babel/plugin-proposal-do-expressions": "^7.0.0",
     "@babel/plugin-syntax-dynamic-import": "^7.0.0",
     "@babel/plugin-transform-runtime": "^7.1.0",
     "@babel/preset-env": "^7.1.6",

test/__snapshots__/index.spec.js.snap

@@ -47,6 +47,12 @@ var A = decorated(_class = function A() {
 }) || _class;"
 `;
 
+exports[`do expressions 1`] = `
+"\\"use strict\\";
+
+var a = b ? 'yep' : 'nope';"
+`;
+
 exports[`dynamic imports 1`] = `
 "\\"use strict\\";
 
@@ -85,6 +91,8 @@ var A = decorated(_class = function A() {
 }) || _class;"
 `;
 
+exports[`esm: do expressions 1`] = `"var a = b ? 'yep' : 'nope';"`;
+
 exports[`esm: dynamic imports 1`] = `"import('./a');"`;
 
 exports[`esm: flow 1`] = `"var a = 'hello';"`;

test/index.spec.js

@@ -28,6 +28,19 @@ let cases = [
       class A { a = () => 'hello' }
     `,
   ],
+  [
+    'do expressions',
+    `
+      let a = do {
+        if (b) {
+          'yep';
+        }
+        else {
+          'nope';
+        }
+      };
+    `,
+  ],
   [
     'decorators legacy',
     `