From 08b8a5f2e7d841aa6303dafaf1092800a8e07f2e Mon Sep 17 00:00:00 2001
From: Christopher Chedeau <vjeuxx@gmail.com>
Date: Mon, 27 Feb 2017 13:46:17 -0800
Subject: [PATCH] Do not put parenthesis around not named default export (#819)

We need to add parenthesis around function expressions if they are named otherwise the name leak, but if the function is not named then it's just superfluous.

The conditional change is due to a bad use of switch case where it would fall through the next one. We don't want parenthesis there.
---
 src/fast-path.js                                 |  9 ++++++++-
 .../conditional/__snapshots__/jsfmt.spec.js.snap | 16 ++++++++--------
 .../es6modules/__snapshots__/jsfmt.spec.js.snap  |  4 ++--
 3 files changed, 18 insertions(+), 11 deletions(-)

diff --git a/src/fast-path.js b/src/fast-path.js
index c980c5b7e..b2decbe90 100644
--- a/src/fast-path.js
+++ b/src/fast-path.js
@@ -451,9 +451,16 @@ FPp.needsParens = function(assumeExpressionContext) {
           if (parent.test === node) {
             return true;
           }
+          return false;
 
         case "ExportDefaultDeclaration":
-          return node.type !== "ArrowFunctionExpression";
+          if (node.type === "ArrowFunctionExpression") {
+            return false;
+          }
+          if (node.type === "FunctionExpression" && !node.id) {
+            return false;
+          }
+          return true;
 
         case "ExpressionStatement":
         case "MemberExpression":
diff --git a/tests/conditional/__snapshots__/jsfmt.spec.js.snap b/tests/conditional/__snapshots__/jsfmt.spec.js.snap
index c8095d6e8..bce41884e 100644
--- a/tests/conditional/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/conditional/__snapshots__/jsfmt.spec.js.snap
@@ -41,23 +41,23 @@ const { configureStore } = process.env.NODE_ENV === \\"production\\"
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 var inspect = 4 === util.inspect.length
   ? // node <= 0.8.x
-    (function(v, colors) {
+    function(v, colors) {
       return util.inspect(v, void 0, void 0, colors);
-    })
+    }
   : // node > 0.8.x
-    (function(v, colors) {
+    function(v, colors) {
       return util.inspect(v, { colors: colors });
-    });
+    };
 
 var inspect = 4 === util.inspect.length
   ? // node <= 0.8.x
-    (function(v, colors) {
+    function(v, colors) {
       return util.inspect(v, void 0, void 0, colors);
-    })
+    }
   : // node > 0.8.x
-    (function(v, colors) {
+    function(v, colors) {
       return util.inspect(v, { colors: colors });
-    });
+    };
 
 const extractTextPluginOptions = shouldUseRelativeAssetPaths
   ? // Making sure that the publicPath goes back to to build folder.
diff --git a/tests/es6modules/__snapshots__/jsfmt.spec.js.snap b/tests/es6modules/__snapshots__/jsfmt.spec.js.snap
index d656f12e1..6178a366e 100644
--- a/tests/es6modules/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/es6modules/__snapshots__/jsfmt.spec.js.snap
@@ -101,14 +101,14 @@ export default function f() {}
 exports[`export_default_function_expression.js 1`] = `
 "export default (function() {});
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-export default (function() {});
+export default function() {};
 "
 `;
 
 exports[`export_default_function_expression.js 2`] = `
 "export default (function() {});
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-export default (function() {});
+export default function() {};
 "
 `;