Ticket #35069: 35069.2.diff

src/wp-includes/pluggable.php

@@ -245 +245 @@
          */
         $atts = apply_filters( 'wp_mail', compact( 'to', 'subject', 'message', 'headers', 'attachments' ) );
 
+        if ( ! is_array( $atts ) ) {
+           return $atts;
+        }
+
         if ( isset( $atts['to'] ) ) {
                 $to = $atts['to'];
         }

tests/phpunit/tests/mail.php

@@ -288 +288 @@
 
                 $this->assertNotContains( 'quoted-printable', $GLOBALS['phpmailer']->mock_sent[0]['header'] );
         }
+
+        /**
+         * @ticket 35069
+         */
+        public function test_wp_mail_bail_early() {
+                $this->assertTrue( wp_mail( WP_TESTS_EMAIL, 'Foo', 'Bar' ) );
+
+                add_filter( 'wp_mail', '__return_false' );
+                $this->assertFalse( wp_mail( WP_TESTS_EMAIL, 'Foo', 'Bar' ) );
+                remove_filter( 'wp_mail', '__return_false' );
+
+                add_filter( 'wp_mail', '__return_empty_string' );
+                $this->assertSame( '', wp_mail( WP_TESTS_EMAIL, 'Foo', 'Bar' ) );
+                remove_filter( 'wp_mail', '__return_empty_string' );
+        }
 }