Adds working example for issue 155

Author: SQiShER

src/integration-test/java/de/danielbechler/diff/issues/issue155/MapIssuesTest.groovy

@@ -0,0 +1,80 @@
+/*
+ * Copyright 2016 Daniel Bechler
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package de.danielbechler.diff.issues.issue155
+
+import de.danielbechler.diff.ObjectDifferBuilder
+import de.danielbechler.diff.identity.IdentityStrategy
+import de.danielbechler.diff.node.DiffNode
+import de.danielbechler.diff.node.Visit
+import de.danielbechler.diff.path.NodePath
+import de.danielbechler.diff.selector.CollectionItemElementSelector
+import de.danielbechler.diff.selector.MapKeyElementSelector
+import spock.lang.Specification
+
+public class MapIssuesTest extends Specification {
+
+	static class LocationIdentityStrategy implements IdentityStrategy {
+
+		@Override
+		boolean equals(workingLocation, baseLocation) {
+			if (workingLocation.city == baseLocation.city) {
+				return true
+			}
+			return false
+		}
+	}
+
+	static class LeafNodeCountingVisitor implements DiffNode.Visitor {
+		int leafNodeCount = 0
+
+		@Override
+		void node(DiffNode node, Visit visit) {
+			if (node.childCount() == 0) {
+				leafNodeCount++;
+			}
+		}
+	}
+
+	def 'compare with collections'() {
+		given:
+		  def sharedCity = 'city'
+		  def working = [name: 'alice', locations: [[street: 'street1', city: sharedCity]]]
+		  def base = [name: 'alice', locations: [[street: 'street2', city: sharedCity]]]
+
+		when:
+		  def locationPath = NodePath.startBuilding().mapKey('locations').build()
+		  def locationIdentityStrategy = new LocationIdentityStrategy()
+		  def node = ObjectDifferBuilder.startBuilding()
+				  .identity()
+				  .ofCollectionItems(locationPath).via(locationIdentityStrategy)
+				  .and().build()
+				  .compare(working, base);
+
+		then:
+		  def leafNodeCountingVisitor = new LeafNodeCountingVisitor()
+		  node.visit(leafNodeCountingVisitor)
+		  leafNodeCountingVisitor.leafNodeCount == 1
+
+		and:
+		  def streetNode = node.getChild([
+				  new MapKeyElementSelector('locations'),
+				  new CollectionItemElementSelector([city: sharedCity]),
+				  new MapKeyElementSelector('street')
+		  ])
+		  streetNode.state == DiffNode.State.CHANGED
+	}
+}