Add testcase and changelog entry for #5278
diff --git a/tests/codeigniter/helpers/url_helper_test.php b/tests/codeigniter/helpers/url_helper_test.php
index 24823a6..5fbc364 100644
--- a/tests/codeigniter/helpers/url_helper_test.php
+++ b/tests/codeigniter/helpers/url_helper_test.php
@@ -53,7 +53,8 @@
 			'<br />www.google.com' => '<br /><a href="http://www.google.com">www.google.com</a>',
 			'Download CodeIgniter at www.codeigniter.com. Period test.' => 'Download CodeIgniter at <a href="http://www.codeigniter.com">www.codeigniter.com</a>. Period test.',
 			'Download CodeIgniter at www.codeigniter.com, comma test' => 'Download CodeIgniter at <a href="http://www.codeigniter.com">www.codeigniter.com</a>, comma test',
-			'This one: ://codeigniter.com must not break this one: http://codeigniter.com' => 'This one: <a href="://codeigniter.com">://codeigniter.com</a> must not break this one: <a href="http://codeigniter.com">http://codeigniter.com</a>'
+			'This one: ://codeigniter.com must not break this one: http://codeigniter.com' => 'This one: <a href="://codeigniter.com">://codeigniter.com</a> must not break this one: <a href="http://codeigniter.com">http://codeigniter.com</a>',
+			'Trailing slash: https://codeigniter.com/ fubar' => 'Trailing slash: <a href="https://codeigniter.com/">https://codeigniter.com/</a> fubar'
 		);
 
 		foreach ($strings as $in => $out)
@@ -76,4 +77,4 @@
 		}
 	}
 
-}
\ No newline at end of file
+}
diff --git a/user_guide_src/source/changelog.rst b/user_guide_src/source/changelog.rst
index 2dd77e3..1c71b09 100644
--- a/user_guide_src/source/changelog.rst
+++ b/user_guide_src/source/changelog.rst
@@ -12,6 +12,7 @@
 
 -  Fixed a regression (#5276) - :doc:`Database Utilities <database/utilities>` method ``backup()`` generated incorrect ``INSERT`` statements with the 'mysqli' driver.
 -  Fixed a regression where :doc:`Database Results <database/results>` method ``field_data()`` returned incorrect type names.
+-  Fixed a bug (#5278) - :doc:`URL Helper <helpers/url_helper>` function :php:func:`auto_link()` didn't detect trailing slashes in URLs.
 
 Version 3.1.6
 =============