Finished MapDiffer tests

Author: SQiShER

src/main/java/de/danielbechler/diff/map/MapEntryAccessor.java

@@ -22,7 +22,9 @@
 
 import java.util.Map;
 
-/** @author Daniel Bechler */
+/**
+ * @author Daniel Bechler
+ */
 public final class MapEntryAccessor implements Accessor
 {
 	private final Object referenceKey;
@@ -33,18 +35,53 @@ public MapEntryAccessor(final Object referenceKey)
 		this.referenceKey = referenceKey;
 	}
 
-	public Element getPathElement()
+	public Object getKey(final Map<?, ?> target)
 	{
-		return new MapElement(referenceKey);
+		final Map<Object, Object> map = objectToMap(target);
+		if (map == null)
+		{
+			return null;
+		}
+		final Object referenceKey = this.referenceKey;
+		for (final Object key : map.keySet())
+		{
+			if (key == referenceKey || key.equals(referenceKey))
+			{
+				return key;
+			}
+		}
+		return null;
 	}
 
-	public void set(final Object target, final Object value)
+	@Override
+	public int hashCode()
 	{
-		final Map<Object, Object> targetMap = objectToMap(target);
-		if (targetMap != null)
+		return referenceKey.hashCode();
+	}
+
+	@Override
+	public boolean equals(final Object o)
+	{
+		if (this == o)
 		{
-			targetMap.put(referenceKey, value);
+			return true;
 		}
+		if (o == null || getClass() != o.getClass())
+		{
+			return false;
+		}
+		return referenceKey.equals(((MapEntryAccessor) o).referenceKey);
+	}
+
+	@Override
+	public String toString()
+	{
+		return "map key " + getPathElement();
+	}
+
+	public Element getPathElement()
+	{
+		return new MapElement(referenceKey);
 	}
 
 	public Object get(final Object target)
@@ -57,18 +94,13 @@ public Object get(final Object target)
 		return null;
 	}
 
-	private static Map<Object, Object> objectToMap(final Object object)
+	public void set(final Object target, final Object value)
 	{
-		if (object == null)
-		{
-			return null;
-		}
-		if (object instanceof Map)
+		final Map<Object, Object> targetMap = objectToMap(target);
+		if (targetMap != null)
 		{
-			//noinspection unchecked
-			return (Map<Object, Object>) object;
+			targetMap.put(referenceKey, value);
 		}
-		throw new IllegalArgumentException(object.getClass().toString());
 	}
 
 	public void unset(final Object target)
@@ -80,55 +112,17 @@ public void unset(final Object target)
 		}
 	}
 
-	@Override
-	public String toString()
-	{
-		return "map key " + getPathElement();
-	}
-
-	public Object getKey(final Map<?, ?> target)
+	private static Map<Object, Object> objectToMap(final Object object)
 	{
-		final Map<Object, Object> map = objectToMap(target);
-		if (map == null)
+		if (object == null)
 		{
 			return null;
 		}
-		final Object referenceKey = this.referenceKey;
-		for (final Object key : map.keySet())
-		{
-			if (key == referenceKey || key.equals(referenceKey))
-			{
-				return key;
-			}
-		}
-		return null;
-	}
-
-	@Override
-	public boolean equals(Object o)
-	{
-		if (this == o)
-		{
-			return true;
-		}
-		if (o == null || getClass() != o.getClass())
-		{
-			return false;
-		}
-
-		MapEntryAccessor that = (MapEntryAccessor) o;
-
-		if (referenceKey != null ? !referenceKey.equals(that.referenceKey) : that.referenceKey != null)
+		if (object instanceof Map)
 		{
-			return false;
+			//noinspection unchecked
+			return (Map<Object, Object>) object;
 		}
-
-		return true;
-	}
-
-	@Override
-	public int hashCode()
-	{
-		return referenceKey != null ? referenceKey.hashCode() : 0;
+		throw new IllegalArgumentException(object.getClass().toString());
 	}
 }

src/test/java/de/danielbechler/diff/map/MapEntryAccessorTest.groovy

@@ -20,7 +20,9 @@ import de.danielbechler.diff.mock.ObjectWithIdentityAndValue
 import spock.lang.Shared
 import spock.lang.Specification
 
-/** @author Daniel Bechler              */
+/**
+ * @author Daniel Bechler
+ */
 class MapEntryAccessorTest extends Specification {
 
     @Shared
@@ -156,4 +158,30 @@ class MapEntryAccessorTest extends Specification {
         then:
         notThrown Throwable
     }
+
+    def "equals should work as expected"() {
+        given:
+        def accessor = new MapEntryAccessor("a")
+
+        expect:
+        accessor.equals(otherAccessor) == expectedResult
+
+        and: "make sure the same instance is always equal"
+        accessor.equals(accessor)
+
+        where:
+        otherAccessor             || expectedResult
+        null                      || false
+        "foo"                     || false
+        new MapEntryAccessor("b") || false
+        new MapEntryAccessor("a") || true
+    }
+
+    def "hashCode should equal hashCode of referenceKey"() {
+        setup:
+        def referenceKey = "foo"
+
+        expect:
+        new MapEntryAccessor(referenceKey).hashCode() == referenceKey.hashCode()
+    }
 }