diff --git a/src/wp-includes/comment-template.php b/src/wp-includes/comment-template.php
index 09969c81da..92ba74fb55 100644
--- a/src/wp-includes/comment-template.php
+++ b/src/wp-includes/comment-template.php
@@ -293,8 +293,13 @@ function comment_author_IP( $comment_ID = 0 ) {
  */
 function get_comment_author_url( $comment_ID = 0 ) {
 	$comment = get_comment( $comment_ID );
-	$url = ('http://' == $comment->comment_author_url) ? '' : $comment->comment_author_url;
-	$url = esc_url( $url, array('http', 'https') );
+	$url = '';
+	$id = 0;
+	if ( ! empty( $comment ) ) {
+		$author_url = ( 'http://' == $comment->comment_author_url ) ? '' : $comment->comment_author_url;
+		$url = esc_url( $author_url, array( 'http', 'https' ) );
+		$id = $comment->ID;
+	}
 
 	/**
 	 * Filter the comment author's URL.
@@ -306,7 +311,7 @@ function get_comment_author_url( $comment_ID = 0 ) {
 	 * @param int        $comment_ID The comment ID.
 	 * @param WP_Comment $comment    The comment object.
 	 */
-	return apply_filters( 'get_comment_author_url', $url, $comment->comment_ID, $comment );
+	return apply_filters( 'get_comment_author_url', $url, $id, $comment );
 }
 
 /**
@@ -345,17 +350,20 @@ function comment_author_url( $comment_ID = 0 ) {
  * in the order of $before, link, and finally $after.
  *
  * @since 1.5.0
+ * @since 4.6.0 The `$comment` parameter was added.
  *
- * @param string $linktext Optional. The text to display instead of the comment
- *                         author's email address. Default empty.
- * @param string $before   Optional. The text or HTML to display before the email link.
- *                         Default empty.
- * @param string $after    Optional. The text or HTML to display after the email link.
- *                         Default empty.
+ * @param string         $linktext Optional. The text to display instead of the comment
+ *                                 author's email address. Default empty.
+ * @param string         $before   Optional. The text or HTML to display before the email link.
+ *                                 Default empty.
+ * @param string         $after    Optional. The text or HTML to display after the email link.
+ *                                 Default empty.
+ * @param int|WP_Comment $comment  Optional. Comment ID or WP_Comment object.
+ *                                 Default is the current comment.
  * @return string The HTML link between the $before and $after parameters.
  */
-function get_comment_author_url_link( $linktext = '', $before = '', $after = '' ) {
-	$url = get_comment_author_url();
+function get_comment_author_url_link( $linktext = '', $before = '', $after = '', $comment = 0 ) {
+	$url = get_comment_author_url( $comment );
 	$display = ($linktext != '') ? $linktext : $url;
 	$display = str_replace( 'http://www.', '', $display );
 	$display = str_replace( 'http://', '', $display );
@@ -380,16 +388,19 @@ function get_comment_author_url_link( $linktext = '', $before = '', $after = ''
  * Displays the HTML link of the url of the author of the current comment.
  *
  * @since 0.71
+ * @since 4.6.0 The `$comment` parameter was added.
  *
- * @param string $linktext Optional. Text to display instead of the comment author's
- *                         email address. Default empty.
- * @param string $before   Optional. Text or HTML to display before the email link.
- *                         Default empty.
- * @param string $after    Optional. Text or HTML to display after the email link.
- *                         Default empty.
+ * @param string         $linktext Optional. Text to display instead of the comment author's
+ *                                 email address. Default empty.
+ * @param string         $before   Optional. Text or HTML to display before the email link.
+ *                                 Default empty.
+ * @param string         $after    Optional. Text or HTML to display after the email link.
+ *                                 Default empty.
+ * @param int|WP_Comment $comment  Optional. Comment ID or WP_Comment object.
+ *                                 Default is the current comment.
  */
-function comment_author_url_link( $linktext = '', $before = '', $after = '' ) {
-	echo get_comment_author_url_link( $linktext, $before, $after );
+function comment_author_url_link( $linktext = '', $before = '', $after = '', $comment = 0 ) {
+	echo get_comment_author_url_link( $linktext, $before, $after, $comment );
 }
 
 /**
diff --git a/tests/phpunit/tests/comment/getCommentAuthorUrlLink.php b/tests/phpunit/tests/comment/getCommentAuthorUrlLink.php
new file mode 100644
index 0000000000..dd59edca15
--- /dev/null
+++ b/tests/phpunit/tests/comment/getCommentAuthorUrlLink.php
@@ -0,0 +1,86 @@
+<?php
+
+/**
+ * @group comment
+ */
+class Tests_Comment_GetCommentAuthorUrlLink extends WP_UnitTestCase {
+	protected static $comments = array();
+
+	public static function wpSetUpBeforeClass( $factory ) {
+		unset( $GLOBALS['comment'] );
+
+		$comment_ids = $factory->comment->create_post_comments( 0, 1 );
+		self::$comments = array_map( 'get_comment', $comment_ids );
+	}
+
+	public static function wpTearDownAfterClass() {
+		foreach ( self::$comments as $comment ) {
+			wp_delete_comment( $comment, true );
+		}
+	}
+
+	protected function parseCommentAuthorUrl( $comment, $linktext = '' ) {
+		if ( empty( $linktext ) ) {
+			$linktext = rtrim( preg_replace( '#http://(www\.)?#', '', $comment->comment_author_url ), '/' );
+		}
+		return sprintf(
+			'<a href=\'%s\' rel=\'external\'>%s</a>',
+			$comment->comment_author_url,
+			$linktext
+		);
+	}
+
+	public function test_no_comment() {
+		$url_link = get_comment_author_url_link();
+
+		$this->assertEquals( "<a href='' rel='external'></a>", $url_link );
+	}
+
+	public function test_global_comment() {
+		$GLOBALS['comment'] = $comment = reset( self::$comments );
+
+		$url_link = get_comment_author_url_link();
+		$link = $this->parseCommentAuthorUrl( $comment );
+		$this->assertEquals( $link, $url_link );
+	}
+
+	public function test_comment_arg() {
+		$comment = reset( self::$comments );
+
+		$url_link = get_comment_author_url_link( '', '', '', $comment );
+		$link = $this->parseCommentAuthorUrl( $comment );
+		$this->assertEquals( $link, $url_link );
+	}
+
+	public function test_linktext() {
+		$comment = reset( self::$comments );
+
+		$url_link = get_comment_author_url_link( 'Burrito', '', '', $comment );
+		$link = $this->parseCommentAuthorUrl( $comment, 'Burrito' );
+		$this->assertEquals( $link, $url_link );
+	}
+
+	public function test_before() {
+		$comment = reset( self::$comments );
+
+		$url_link = get_comment_author_url_link( 'Burrito', 'I would love a ', '', $comment );
+		$link = 'I would love a ' . $this->parseCommentAuthorUrl( $comment, 'Burrito' );
+		$this->assertEquals( $link, $url_link );
+	}
+
+	public function test_after() {
+		$comment = reset( self::$comments );
+
+		$url_link = get_comment_author_url_link( 'Burrito', '', ' is my favorite word.', $comment );
+		$link = $this->parseCommentAuthorUrl( $comment, 'Burrito' ) . ' is my favorite word.';
+		$this->assertEquals( $link, $url_link );
+	}
+
+	public function test_before_after() {
+		$comment = reset( self::$comments );
+
+		$url_link = get_comment_author_url_link( 'Burrito', 'I would love a ', ' right now.', $comment );
+		$link = 'I would love a ' . $this->parseCommentAuthorUrl( $comment, 'Burrito' ) . ' right now.';
+		$this->assertEquals( $link, $url_link );
+	}
+}