From cdeff2fbb1f55b3b15a495520415f1b4f0f0b5cb Mon Sep 17 00:00:00 2001
From: Sebastian McKenzie <sebmck@gmail.com>
Date: Tue, 3 Nov 2015 10:49:24 +0000
Subject: [PATCH] simplify parentheses logic and properly parenthesise unaries
 - fixes #2711

---
 .../babel-generator/src/node/parentheses.js   | 36 +++++++------------
 .../fixtures/types/UnaryExpression/actual.js  |  2 ++
 .../types/UnaryExpression/expected.js         |  2 ++
 3 files changed, 16 insertions(+), 24 deletions(-)

diff --git a/packages/babel-generator/src/node/parentheses.js b/packages/babel-generator/src/node/parentheses.js
index 3b6d1d6e1c..4f488956e7 100644
--- a/packages/babel-generator/src/node/parentheses.js
+++ b/packages/babel-generator/src/node/parentheses.js
@@ -154,7 +154,15 @@ export function ClassExpression(node: Object, parent: Object): boolean {
 }
 
 export function UnaryLike(node: Object, parent: Object): boolean {
-  return t.isMemberExpression(parent) && parent.object === node;
+  if (t.isMemberExpression(parent, { object: node })) {
+    return true;
+  }
+
+  if (t.isCallExpression(parent, { callee: node }) || t.isNewExpression(parent, { callee: node })) {
+    return true;
+  }
+
+  return false;
 }
 
 export function FunctionExpression(node: Object, parent: Object): boolean {
@@ -172,17 +180,7 @@ export function ArrowFunctionExpression(node: Object, parent: Object): boolean {
     return true;
   }
 
-  // (function test() {}).name;
-  if (t.isMemberExpression(parent) && parent.object === node) {
-    return true;
-  }
-
-  // (function () {})();
-  if (t.isCallExpression(parent) && parent.callee === node) {
-    return true;
-  }
-
-  return false;
+  return UnaryLike(node, parent);
 }
 
 export function ConditionalExpression(node: Object, parent: Object): boolean {
@@ -194,21 +192,11 @@ export function ConditionalExpression(node: Object, parent: Object): boolean {
     return true;
   }
 
-  if (t.isCallExpression(parent) || t.isNewExpression(parent)) {
-    if (parent.callee === node) {
-      return true;
-    }
-  }
-
-  if (t.isConditionalExpression(parent) && parent.test === node) {
+  if (t.isConditionalExpression(parent, { test: node })) {
     return true;
   }
 
-  if (t.isMemberExpression(parent) && parent.object === node) {
-    return true;
-  }
-
-  return false;
+  return UnaryLike(node, parent);
 }
 
 export function AssignmentExpression(node: Object): boolean {
diff --git a/packages/babel-generator/test/fixtures/types/UnaryExpression/actual.js b/packages/babel-generator/test/fixtures/types/UnaryExpression/actual.js
index 9f318cdb1f..58154c99cf 100644
--- a/packages/babel-generator/test/fixtures/types/UnaryExpression/actual.js
+++ b/packages/babel-generator/test/fixtures/types/UnaryExpression/actual.js
@@ -3,3 +3,5 @@ delete delete i;
 !!i;
 + ++i;
 - --i;
+typeof a();
+(typeof a)();
diff --git a/packages/babel-generator/test/fixtures/types/UnaryExpression/expected.js b/packages/babel-generator/test/fixtures/types/UnaryExpression/expected.js
index 9f318cdb1f..58154c99cf 100644
--- a/packages/babel-generator/test/fixtures/types/UnaryExpression/expected.js
+++ b/packages/babel-generator/test/fixtures/types/UnaryExpression/expected.js
@@ -3,3 +3,5 @@ delete delete i;
 !!i;
 + ++i;
 - --i;
+typeof a();
+(typeof a)();