Core: Add test for jQuery.ready.promise fallback load

Fix #13655
Close gh-1209
Ref 32b066d3

test/data/core/dont_return.php

+<?php
+sleep(10000);
+?>

test/data/core/dynamic_ready.html

+<!DOCTYPE html>
+<html>
+<head>
+	<meta charset="utf-8">
+	<script src="../../jquery.js"></script>
+	<script>var $j = jQuery.noConflict();</script>
+</head>
+<body>
+<iframe id="dont_return" src="dont_return.php"></iframe>
+<script>
+	var timeoutId, $,
+		timeoutFired = false;
+
+	setTimeout(function () {
+		// Load another jQuery copy using the first one.
+		$j.getScript( "../../../dist/jquery.js", function () {
+			$j( "#dont_return" ).attr( "src", "about:blank" );
+
+			// document ready handled by the just-loaded jQuery copy.
+			$(function () {
+				clearTimeout( timeoutId );
+				if ( !timeoutFired ) {
+					window.parent.iframeCallback( true );
+				}
+			});
+		});
+
+		timeoutId = setTimeout(function () {
+			timeoutFired = true;
+			window.parent.iframeCallback( false );
+		}, 3000);
+	});
+</script>
+</body>
+</html>

test/unit/core.js

@@ -1486,6 +1486,11 @@ testIframeWithCallback( "Conditional compilation compatibility (#13274)", "core/
 	ok( $(), "jQuery executes" );
 });
 
+testIframeWithCallback( "document ready when jQuery loaded asynchronously (#13655)", "core/dynamic_ready.html", function( ready ) {
+	expect( 1 );
+	equal( true, ready, "document ready correctly fired when jQuery is loaded after DOMContentLoaded" );
+});
+
 testIframeWithCallback( "Tolerating alias-masked DOM properties (#14074)", "core/aliased.html",
 	function( errors ) {
 			expect( 1 );