SWF-1132 - Spring WebFlow throws IllegalArgumentException while binding map entries

spring-webflow/src/main/java/org/springframework/webflow/mvc/view/BindingModel.java

@@ -53,6 +53,7 @@ import org.springframework.webflow.engine.builder.BinderConfiguration.Binding;
  * @see AbstractMvcView
  * 
  * @author Keith Donald
+ * @author Jeremy Grelle
  */
 public class BindingModel extends AbstractErrors implements BindingResult {
 
@@ -189,7 +190,11 @@ public class BindingModel extends AbstractErrors implements BindingResult {
 					valueType = parseFieldExpression(field).getValueType(boundObject);
 				}
 			}
-			return new ConversionExecutorPropertyEditor(conversionService, valueType, converterId);
+			if (valueType != null) {
+				return new ConversionExecutorPropertyEditor(conversionService, valueType, converterId);
+			} else {
+				return null;
+			}
 		} else {
 			return null;
 		}

spring-webflow/src/test/java/org/springframework/webflow/TestBean.java

@@ -17,6 +17,8 @@ package org.springframework.webflow;
 
 import java.io.Serializable;
 import java.util.Date;
+import java.util.HashMap;
+import java.util.Map;
 
 /**
  * Simple test bean used by some test cases. Note that this bean has value semantics.
@@ -31,6 +33,8 @@ public class TestBean implements Serializable {
 
 	public boolean executed;
 
+	public Map emptyMap;
+
 	public void execute() {
 		this.executed = true;
 	}
@@ -47,6 +51,14 @@ public class TestBean implements Serializable {
 		return datum3;
 	}
 
+	public Map getEmptyMap() {
+		if (emptyMap == null) {
+			emptyMap = new HashMap();
+			emptyMap.put("foo", null);
+		}
+		return emptyMap;
+	}
+
 	public void setDatum3(Date datum3) {
 		this.datum3 = datum3;
 	}

spring-webflow/src/test/java/org/springframework/webflow/mvc/view/AbstractBindingModelTests.java

@@ -21,9 +21,8 @@ import org.springframework.validation.FieldError;
 import org.springframework.webflow.TestBean;
 import org.springframework.webflow.engine.builder.BinderConfiguration;
 import org.springframework.webflow.engine.builder.BinderConfiguration.Binding;
-import org.springframework.webflow.expression.DefaultExpressionParserFactory;
 
-public class BindingModelTests extends TestCase {
+public abstract class AbstractBindingModelTests extends TestCase {
 
 	BindingModel model;
 	DefaultMessageContext messages;
@@ -35,10 +34,12 @@ public class BindingModelTests extends TestCase {
 		testBean = new TestBean();
 		messages = new DefaultMessageContext();
 		conversionService = new DefaultConversionService();
-		expressionParser = DefaultExpressionParserFactory.getExpressionParser();
+		expressionParser = getExpressionParser();
 		model = new BindingModel("testBean", testBean, expressionParser, conversionService, messages);
 	}
 
+	protected abstract ExpressionParser getExpressionParser();
+
 	public void testInitialState() {
 		assertEquals(0, model.getErrorCount());
 		assertEquals(0, model.getFieldErrorCount());
@@ -66,8 +67,7 @@ public class BindingModelTests extends TestCase {
 	}
 
 	public void testGetFieldValueNonStringNoConversionService() {
-		model = new BindingModel("testBean", testBean, DefaultExpressionParserFactory.getExpressionParser(), null,
-				messages);
+		model = new BindingModel("testBean", testBean, getExpressionParser(), null, messages);
 		testBean.datum2 = 3;
 		assertEquals(new Integer(3), model.getFieldValue("datum2"));
 	}

spring-webflow/src/test/java/org/springframework/webflow/mvc/view/DefaultBindingModelTests.java

@@ -0,0 +1,11 @@
+package org.springframework.webflow.mvc.view;
+
+import org.springframework.binding.expression.ExpressionParser;
+import org.springframework.webflow.expression.DefaultExpressionParserFactory;
+
+public class DefaultBindingModelTests extends AbstractBindingModelTests {
+
+	protected ExpressionParser getExpressionParser() {
+		return DefaultExpressionParserFactory.getExpressionParser();
+	}
+}

spring-webflow/src/test/java/org/springframework/webflow/mvc/view/SpringBeanBindingModelTests.java

@@ -0,0 +1,19 @@
+package org.springframework.webflow.mvc.view;
+
+import java.beans.PropertyEditor;
+
+import org.springframework.binding.expression.ExpressionParser;
+import org.springframework.binding.expression.beanwrapper.BeanWrapperExpressionParser;
+
+public class SpringBeanBindingModelTests extends AbstractBindingModelTests {
+
+	protected ExpressionParser getExpressionParser() {
+		return new BeanWrapperExpressionParser();
+	}
+
+	// See SWF-1132
+	public void testFindPropertyEditorForUndeterminableType() {
+		PropertyEditor editor = model.findEditor("emptyMap['foo']", null);
+		assertNull(editor);
+	}
+}