From 6fa40d98070dd4b5eff679a603f117444c31c716 Mon Sep 17 00:00:00 2001
From: Dina Berry <diberry@microsoft.com>
Date: Sun, 10 Mar 2019 05:56:05 -0700
Subject: [PATCH] #470 fix

---
 lib/js-yaml/dumper.js | 18 ++++++-----------
 test/issues/0470.js   | 46 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 52 insertions(+), 12 deletions(-)
 create mode 100644 test/issues/0470.js

diff --git a/lib/js-yaml/dumper.js b/lib/js-yaml/dumper.js
index 86f34794..356e107a 100644
--- a/lib/js-yaml/dumper.js
+++ b/lib/js-yaml/dumper.js
@@ -194,14 +194,7 @@ function isPlainSafe(c) {
   // where nb-char ::= c-printable - b-char - c-byte-order-mark.
   return isPrintable(c) && c !== 0xFEFF
     // - c-flow-indicator
-    && c !== CHAR_COMMA
-    && c !== CHAR_LEFT_SQUARE_BRACKET
-    && c !== CHAR_RIGHT_SQUARE_BRACKET
-    && c !== CHAR_LEFT_CURLY_BRACKET
-    && c !== CHAR_RIGHT_CURLY_BRACKET
-    // - ":" - "#"
-    && c !== CHAR_COLON
-    && c !== CHAR_SHARP;
+    && c !== CHAR_COLON;
 }
 
 // Simplified test for values allowed as the first character in plain style.
@@ -272,7 +265,7 @@ function chooseScalarStyle(string, singleLineOnly, indentPerLevel, lineWidth, te
       if (!isPrintable(char)) {
         return STYLE_DOUBLE;
       }
-      plain = plain && isPlainSafe(char);
+      plain = plain && (isPlainSafe(char) && !isWhitespace(string.charCodeAt(i + 1)));
     }
   } else {
     // Case: block styles permitted.
@@ -291,12 +284,14 @@ function chooseScalarStyle(string, singleLineOnly, indentPerLevel, lineWidth, te
       } else if (!isPrintable(char)) {
         return STYLE_DOUBLE;
       }
-      plain = plain && isPlainSafe(char);
+      if (!isPlainSafe(char)) {
+        plain = plain && !isWhitespace(string.charCodeAt(i + 1));
+      }
     }
     // in case the end is missing a \n
     hasFoldableLine = hasFoldableLine || (shouldTrackWidth &&
       (i - previousLineBreak - 1 > lineWidth &&
-       string[previousLineBreak + 1] !== ' '));
+      string[previousLineBreak + 1] !== ' '));
   }
   // Although every style can represent \n without escaping, prefer block styles
   // for multiline, since they're more readable and they don't add empty lines.
@@ -760,7 +755,6 @@ function writeNode(state, level, object, block, compact, iskey) {
       state.dump = '!<' + state.tag + '> ' + state.dump;
     }
   }
-
   return true;
 }
 
diff --git a/test/issues/0470.js b/test/issues/0470.js
new file mode 100644
index 00000000..13d2a6c6
--- /dev/null
+++ b/test/issues/0470.js
@@ -0,0 +1,46 @@
+'use strict';
+
+var assert = require('assert');
+var yaml = require('../..');
+
+test('should not unnecessaryly apply quotes', function () {
+
+  var expected = 'url: https://github.com/nodeca/js-yaml\n';
+  var actual = yaml.dump(
+    {
+      url: 'https://github.com/nodeca/js-yaml'
+    }
+  );
+
+  assert.strictEqual(actual, expected);
+});
+test('should not unnecessaryly apply quotes - ', function () {
+
+  var expected = 'url: https://github.com/nodeca/js-yaml\n';
+
+  var obj = {};
+  obj['url'] = 'https://github.com/nodeca/js-yaml';
+
+  var actual = yaml.dump(obj);
+
+  assert.strictEqual(actual, expected);
+});
+
+test('should not unnecessaryly apply quotes - space then /\n at end of value', function () {
+
+  var expected = 'url: \'https://github.com/nodeca/js-yaml \'\n';
+
+  var obj = {};
+  obj['url'] = 'https://github.com/nodeca/js-yaml ';
+
+  var actual = yaml.dump(obj);
+
+  assert.strictEqual(actual, expected);
+});
+test('should not unnecessaryly apply quotes - space after colon', function () {
+
+  var expected = 'url: \'https: //github.com/nodeca/js-yaml\'\n';
+  var actual = yaml.dump({ url: 'https: //github.com/nodeca/js-yaml' });
+
+  assert.strictEqual(actual, expected);
+});