Ajax: Protect against exceptions thrown synchronously by xhr.send

When xhr.send throws an exception synchronously, the onerror handler may have
been called already which, unchecked, makes the exception bubble up outside of
jQuery.ajax.

We now catch the exception pre-emptively and only rethrow if we know it hasn't
already been notified through the onerror handler.

Fixes #14683

diff --git a/src/ajax/xhr.js b/src/ajax/xhr.js
index 55d526a4191339c16ac4908a6be4771aee57e4ac..bdeeee3f8220042cdb533685f67ced7b753c35dc 100644 (file)
--- a/src/ajax/xhr.js
+++ b/src/ajax/xhr.js
@@ -112,10 +112,15 @@ jQuery.ajaxTransport(function( options ) {
                                // Create the abort callback
                                callback = xhrCallbacks[ id ] = callback("abort");
 
-                               // Do send the request
-                               // This may raise an exception which is actually
-                               // handled in jQuery.ajax (so no try/catch here)
-                               xhr.send( options.hasContent && options.data || null );
+                               try {
+                                       // Do send the request (this may raise an exception)
+                                       xhr.send( options.hasContent && options.data || null );
+                               } catch ( e ) {
+                                       // #14683: Only rethrow if this hasn't been notified as an error yet
+                                       if ( callback ) {
+                                               throw e;
+                                       }
+                               }
                        },
 
                        abort: function() {

diff --git a/test/unit/ajax.js b/test/unit/ajax.js
index 77648404cb90c483d044ead0ef34aef1eb440843..c7d7daba4fde894eead37235cbdf2778a1525bca 100644 (file)
--- a/test/unit/ajax.js
+++ b/test/unit/ajax.js
@@ -1544,6 +1544,36 @@ module( "ajax", {
                });
        }
 
+       ajaxTest( "#14683 - jQuery.ajax() - Exceptions thrown synchronously by xhr.send should be caught", 4, [
+               {
+                       url: "data/params_html.php",
+                       method: "POST",
+                       data: {
+                               toString: function() {
+                                       throw "Can't parse";
+                               }
+                       },
+                       processData: false,
+                       done: function( data ) {
+                               ok( false, "done: " + data );
+                       },
+                       fail: function( jqXHR, status, error ) {
+                               ok( true, "exception caught: " + error );
+                               strictEqual( jqXHR.status, 0, "proper status code" );
+                               strictEqual( status, "error", "proper status" );
+                       }
+               },
+               {
+                       url: "http://domain.org:80d",
+                       done: function( data ) {
+                               ok( false, "done: " + data );
+                       },
+                       fail: function( _, status, error ) {
+                               ok( true, "fail: " + status + " - " + error );
+                       }
+               }
+       ]);
+
 //----------- jQuery.ajaxPrefilter()
 
        ajaxTest( "jQuery.ajaxPrefilter() - abort", 1, {