Ajax: Execute JSONP error script responses

Issue gh-4379 was meant to be a bug fix but the JSONP case is a bit special: under the hood it's a script but it simulates JSON responses in an environment without a CORS setup and sending JSON payloads on error responses is quite typical there. This commit makes JSONP error responses still execute the payload. The regular script error responses continue to be skipped. Fixes gh-4771 Closes gh-4773 (cherry picked from commit a1e619b)
jquery · Aug 25, 2020 · 3bae54aa50b7485b1f18501dff038a61507012a5 · 3bae54a
1 parent beea433
commit 3bae54aa50b7485b1f18501dff038a61507012a5
Unified Split

Showing with 17 additions and 2 deletions.

+4 −2 src/ajax.js

+13 −0 test/unit/ajax.js
diff --git a/src/ajax.js b/src/ajax.js
@@ -745,8 +745,10 @@ jQuery.extend( {
 				response = ajaxHandleResponses( s, jqXHR, responses );
 			}
 
-			// Use a noop converter for missing script
-			if ( !isSuccess && jQuery.inArray( "script", s.dataTypes ) > -1 ) {
+			// Use a noop converter for missing script but not if jsonp
+			if ( !isSuccess &&
+				jQuery.inArray( "script", s.dataTypes ) > -1 &&
+				jQuery.inArray( "json", s.dataTypes ) < 0 ) {
 				s.converters[ "text script" ] = function() {};
 			}
 

diff --git a/test/unit/ajax.js b/test/unit/ajax.js
@@ -837,6 +837,19 @@ QUnit.module( "ajax", {
 		};
 	} );
 
+	ajaxTest( "jQuery.ajax() - do execute scripts if JSONP from unsuccessful responses", 1, function( assert ) {
+		var testMsg = "Unsuccessful JSONP requests should have a JSON body";
+		return {
+			dataType: "jsonp",
+			url: url( "mock.php?action=errorWithScript" ),
+			// error is the significant assertion
+			error: function( xhr ) {
+				var expected = { "status": 404, "msg": "Not Found" };
+				assert.deepEqual( xhr.responseJSON, expected, testMsg );
+			}
+		};
+	} );
+
 	ajaxTest( "jQuery.ajax() - do not execute scripts from unsuccessful responses (gh-4250)", 11, function( assert ) {
 		var globalEval = jQuery.globalEval;