Enable custom matching on inherited fields

Fixes shazam#15.

src/main/java/com/shazam/shazamcrest/BeanFinder.java

@@ -9,13 +9,16 @@
  */
 package com.shazam.shazamcrest;
 
-import static java.util.Arrays.asList;
-
 import java.lang.reflect.Field;
 import java.util.Collection;
+import java.util.LinkedList;
 import java.util.List;
 import java.util.regex.Pattern;
 
+import static java.lang.reflect.Modifier.isProtected;
+import static java.lang.reflect.Modifier.isPublic;
+import static java.util.Arrays.asList;
+
 /**
  * Returns the object corresponding to the path specified
  */
@@ -30,7 +33,7 @@ public static Object findBeanAt(String fieldPath, Object object) {
 	}
 
 	private static Object findBeanAt(List<String> fields, Object object) {
-		for (Field field : object.getClass().getDeclaredFields()) {
+		for (Field field : getAllFields(object.getClass())) {
 			field.setAccessible(true);
 			if (headOf(fields).equals(field.getName())) {
 				try {
@@ -42,11 +45,34 @@ private static Object findBeanAt(List<String> fields, Object object) {
 				} catch (IllegalAccessException e) {}
 			}
 		}
-		
+
 		throw new IllegalArgumentException();
 	}
 
 	private static String headOf(final Collection<String> paths) {
 		return paths.iterator().next();
 	}
+
+	private static List<Field> getAllFields(Class<?> type) {
+		List<Field> allFields = new LinkedList<Field>();
+		for (Class<?> clazz = type; clazz != null; clazz = clazz.getSuperclass()) {
+			List<Field> fields = new LinkedList<Field>();
+			for (Field field : clazz.getDeclaredFields()) {
+				int modifiers = field.getModifiers();
+				if (fieldIsVisibleInType(clazz, modifiers, type)) {
+					fields.add(field);
+				}
+			}
+			allFields.addAll(fields);
+		}
+		return allFields;
+	}
+
+	private static boolean fieldIsVisibleInType(Class<?> clazz, int modifiers, Class<?> type) {
+		return isProtected(modifiers) || isPublic(modifiers) || isDefault(modifiers) || clazz.equals(type);
+	}
+
+	private static boolean isDefault(int modifiers) {
+		return modifiers == 0x0;
+	}
 }

src/test/java/com/shazam/shazamcrest/CustomMatcherOnInheritedFieldTest.java

@@ -0,0 +1,50 @@
+package com.shazam.shazamcrest;
+
+import org.junit.Test;
+
+import static com.shazam.shazamcrest.MatcherAssert.assertThat;
+import static com.shazam.shazamcrest.matcher.Matchers.sameBeanAs;
+import static org.hamcrest.Matchers.startsWith;
+
+public class CustomMatcherOnInheritedFieldTest {
+
+    @Test
+    public void inheritedFieldsAreMatchedByCustomMatchers() {
+        assertThat(new ChildClass(), sameBeanAs(new ChildClass())
+                .with("packageProtectedField", startsWith("inherit"))
+                .with("protectedField", startsWith("inherit"))
+                .with("publicField", startsWith("inherit"))
+        );
+    }
+
+    @Test
+    public void notInheritedFieldsAreMatchedByCustomMatchers() {
+        assertThat(new ChildClass(), sameBeanAs(new ChildClass())
+                .with("childField", startsWith("child"))
+        );
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void inheritedPrivateFieldsCanNotBeMatched() {
+        assertThat(new ChildClass(), sameBeanAs(new ChildClass())
+                .with("privateField", startsWith("foo"))
+        );
+    }
+
+    @SuppressWarnings("unused")
+    private class GrandParentClass {
+        private String privateField = "not inherited";
+        String packageProtectedField = "inherited";
+    }
+
+    @SuppressWarnings("unused")
+    private class ParentClass extends GrandParentClass {
+        protected String protectedField = "inherited";
+        public String publicField = "inherited";
+    }
+
+    @SuppressWarnings("unused")
+    private class ChildClass extends ParentClass {
+        private String childField = "child field";
+    }
+}