PropertySourcesPlaceholderConfigurer's "ignoreUnresolvablePlaceholders" setting reliably applies to nested placeholders as well

Issue: SPR-10549

spring-core/src/test/java/org/springframework/core/env/PropertySourcesPropertyResolverTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2013 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -30,8 +30,6 @@ import static org.hamcrest.Matchers.*;
 import static org.junit.Assert.*;
 
 /**
- * Unit tests for {@link PropertySourcesPropertyResolver}.
- *
  * @author Chris Beams
  * @since 3.1
  */
@@ -387,8 +385,8 @@ public class PropertySourcesPropertyResolverTests {
 		try {
 			pr.getProperty("pL");
 		}
-		catch (StackOverflowError ex) {
-			// no explicit handling for cyclic references for now
+		catch (IllegalArgumentException ex) {
+			assertTrue(ex.getMessage().toLowerCase().contains("circular"));
 		}
 	}