From 2acc3e5ea659b493019a7221a52b69d29e2cc32e Mon Sep 17 00:00:00 2001
From: Christopher Chedeau <vjeuxx@gmail.com>
Date: Sun, 22 Jan 2017 19:04:00 -0800
Subject: [PATCH] Add parenthesis around assignment for arrow function body
 (#422)

Fixes #412
---
 src/fast-path.js                              | 6 ++++++
 tests/arrows/__snapshots__/jsfmt.spec.js.snap | 4 ++++
 tests/arrows/arrows.js                        | 2 ++
 3 files changed, 12 insertions(+)

diff --git a/src/fast-path.js b/src/fast-path.js
index ba07bbc41..a531a96fe 100644
--- a/src/fast-path.js
+++ b/src/fast-path.js
@@ -376,6 +376,12 @@ FPp.needsParens = function(assumeExpressionContext) {
         parent.object === node;
 
     case "AssignmentExpression":
+      if (parent.type === "ArrowFunctionExpression" &&
+          parent.body === node &&
+          node.left.type === "ObjectPattern") {
+        return true;
+      }
+
     case "ConditionalExpression":
       switch (parent.type) {
         case "TaggedTemplateExpression":
diff --git a/tests/arrows/__snapshots__/jsfmt.spec.js.snap b/tests/arrows/__snapshots__/jsfmt.spec.js.snap
index 00375d891..3a2606f90 100644
--- a/tests/arrows/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/arrows/__snapshots__/jsfmt.spec.js.snap
@@ -64,6 +64,8 @@ exports[`test arrows.js 1`] = `
     return images.find(image => image.width >= maxPixelWidth) ||
         images[images.length - 1];
 }
+
+a = () => ({} = this);
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 function selectBestEffortImageForWidth(
   maxWidth: number,
@@ -75,6 +77,8 @@ function selectBestEffortImageForWidth(
   return images.find(image => image.width >= maxPixelWidth) ||
     images[images.length - 1];
 }
+
+a = () => ({} = this);
 "
 `;
 
diff --git a/tests/arrows/arrows.js b/tests/arrows/arrows.js
index f25cc0fb3..93f6b3c46 100644
--- a/tests/arrows/arrows.js
+++ b/tests/arrows/arrows.js
@@ -8,3 +8,5 @@ function selectBestEffortImageForWidth(
     return images.find(image => image.width >= maxPixelWidth) ||
         images[images.length - 1];
 }
+
+a = () => ({} = this);