From 00d9aa208e12a1c61e5660ee6be88d35e1e711c8 Mon Sep 17 00:00:00 2001
From: Lucas Azzola <derflatulator@gmail.com>
Date: Sun, 16 Jul 2017 17:45:27 +1000
Subject: [PATCH] Trim trailing whitespace from comments, closes #2422 (#2494)

---
 src/comments.js                                 |  6 +++---
 tests/comments/__snapshots__/jsfmt.spec.js.snap | 15 +++++++++++++++
 tests/comments/trailing_space.js                |  5 +++++
 3 files changed, 23 insertions(+), 3 deletions(-)
 create mode 100644 tests/comments/trailing_space.js

diff --git a/src/comments.js b/src/comments.js
index e0a32a57..c6c8e06d 100644
--- a/src/comments.js
+++ b/src/comments.js
@@ -831,7 +831,7 @@ function printComment(commentPath, options) {
 
   switch (comment.type || comment.kind) {
     case "Comment":
-      return "#" + comment.value;
+      return "#" + comment.value.trimRight();
     case "CommentBlock":
     case "Block":
       return "/*" + comment.value + "*/";
@@ -839,9 +839,9 @@ function printComment(commentPath, options) {
     case "Line":
       // Print shebangs with the proper comment characters
       if (options.originalText.slice(util.locStart(comment)).startsWith("#!")) {
-        return "#!" + comment.value;
+        return "#!" + comment.value.trimRight();
       }
-      return "//" + comment.value;
+      return "//" + comment.value.trimRight();
     default:
       throw new Error("Not a comment: " + JSON.stringify(comment));
   }
diff --git a/tests/comments/__snapshots__/jsfmt.spec.js.snap b/tests/comments/__snapshots__/jsfmt.spec.js.snap
index 11e486f7..8b32979f 100644
--- a/tests/comments/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/comments/__snapshots__/jsfmt.spec.js.snap
@@ -1249,6 +1249,21 @@ d //comment
 
 `;
 
+exports[`trailing_space.js 1`] = `
+#!/there/is-space-here->         
+
+// Do not trim trailing whitespace from this source file!
+
+// There is some space here ->                        
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+#!/there/is-space-here->
+
+// Do not trim trailing whitespace from this source file!
+
+// There is some space here ->
+
+`;
+
 exports[`try.js 1`] = `
 // comment 1
 try {
diff --git a/tests/comments/trailing_space.js b/tests/comments/trailing_space.js
new file mode 100644
index 00000000..c85ebdcb
--- /dev/null
+++ b/tests/comments/trailing_space.js
@@ -0,0 +1,5 @@
+#!/there/is-space-here->         
+
+// Do not trim trailing whitespace from this source file!
+
+// There is some space here ->