From a540cbe8016b1f86d8b9106a40e892893e5dde1c Mon Sep 17 00:00:00 2001
From: Amjad Masad <amjad.masad@gmail.com>
Date: Thu, 30 Apr 2015 05:06:56 -0700
Subject: [PATCH 1/2] Failing test with return not on the same line as it's
 expression

Note that this is not a parenthesis issue but this was the easiest way
to reproduce it. I ran into it when testing generators with `retainLines`
and the generated `return` statement (replacing yeild) was printed on
the line preceding the expression being yielded.
---
 .../edgecase/return-with-retainlines-option/actual.js        | 5 +++++
 .../edgecase/return-with-retainlines-option/expected.js      | 2 ++
 .../edgecase/return-with-retainlines-option/options.json     | 3 +++
 3 files changed, 10 insertions(+)
 create mode 100644 test/core/fixtures/generation/edgecase/return-with-retainlines-option/actual.js
 create mode 100644 test/core/fixtures/generation/edgecase/return-with-retainlines-option/expected.js
 create mode 100644 test/core/fixtures/generation/edgecase/return-with-retainlines-option/options.json

diff --git a/test/core/fixtures/generation/edgecase/return-with-retainlines-option/actual.js b/test/core/fixtures/generation/edgecase/return-with-retainlines-option/actual.js
new file mode 100644
index 0000000000..66e5d50920
--- /dev/null
+++ b/test/core/fixtures/generation/edgecase/return-with-retainlines-option/actual.js
@@ -0,0 +1,5 @@
+function foo(l) {
+  return (
+    l
+  );
+}
diff --git a/test/core/fixtures/generation/edgecase/return-with-retainlines-option/expected.js b/test/core/fixtures/generation/edgecase/return-with-retainlines-option/expected.js
new file mode 100644
index 0000000000..ccb44de809
--- /dev/null
+++ b/test/core/fixtures/generation/edgecase/return-with-retainlines-option/expected.js
@@ -0,0 +1,2 @@
+function foo(l) {
+  return l;}
diff --git a/test/core/fixtures/generation/edgecase/return-with-retainlines-option/options.json b/test/core/fixtures/generation/edgecase/return-with-retainlines-option/options.json
new file mode 100644
index 0000000000..97925bbcb6
--- /dev/null
+++ b/test/core/fixtures/generation/edgecase/return-with-retainlines-option/options.json
@@ -0,0 +1,3 @@
+{
+  "retainLines": true
+}

From 4c2ae5dd1962d62d9e871934f9ed861f78da3d43 Mon Sep 17 00:00:00 2001
From: Amjad Masad <amjad.masad@gmail.com>
Date: Thu, 30 Apr 2015 05:43:08 -0700
Subject: [PATCH 2/2] Parenthesize statement argument when on a different line

---
 src/babel/generation/index.js                     | 15 ++++++++++++---
 .../return-with-retainlines-option/expected.js    |  3 ++-
 2 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/src/babel/generation/index.js b/src/babel/generation/index.js
index ed784c4019..09d74c4fe0 100644
--- a/src/babel/generation/index.js
+++ b/src/babel/generation/index.js
@@ -147,13 +147,22 @@ class CodeGenerator {
     return print;
   }
 
-  catchUp(node) {
+  catchUp(node, parent) {
     // catch up to this nodes newline if we're behind
     if (node.loc && this.format.retainLines && this.buffer.buf) {
+      var needsParens = false;
+      if (parent && (this.position.line < node.loc.start.line) &&
+          (t.isContinueStatement(parent) || t.isBreakStatement(parent) ||
+           t.isReturnStatement(parent) || t.isThrowStatement(parent))) {
+        needsParens = true;
+        this._push("(");
+      }
       while (this.position.line < node.loc.start.line) {
         this._push("\n");
       }
+      return needsParens;
     }
+    return false;
   }
 
   print(node, parent, opts = {}) {
@@ -207,7 +216,7 @@ class CodeGenerator {
 
       this.printLeadingComments(node, parent);
 
-      this.catchUp(node);
+      var needsParensFromCatchup = this.catchUp(node, parent);
 
       newline(true);
 
@@ -220,7 +229,7 @@ class CodeGenerator {
         this.newline();
         this.dedent();
       }
-      if (needsParens) this.push(")");
+      if (needsParens || needsParensFromCatchup) this.push(")");
 
       this.map.mark(node, "end");
       if (opts.after) opts.after();
diff --git a/test/core/fixtures/generation/edgecase/return-with-retainlines-option/expected.js b/test/core/fixtures/generation/edgecase/return-with-retainlines-option/expected.js
index ccb44de809..7b9861c5aa 100644
--- a/test/core/fixtures/generation/edgecase/return-with-retainlines-option/expected.js
+++ b/test/core/fixtures/generation/edgecase/return-with-retainlines-option/expected.js
@@ -1,2 +1,3 @@
 function foo(l) {
-  return l;}
+  return (
+  l);}