Add forceExpand for specific TypeDefinition

fixture-monkey-api/src/main/java/com/navercorp/fixturemonkey/api/tree/DefaultTraverseNode.java

@@ -268,6 +268,27 @@ public void forceExpand() {
 		this.expandedTypeDefinition = resolvedTypeDefinition;
 	}
 
+	@Override
+	public void forceExpand(TypeDefinition typeDefinition) {
+		List<TraverseNode> children;
+		if (this.getTreeProperty().isContainer()) {
+			children = this.expandContainerNode(
+				typeDefinition,
+				traverseContext.withParentProperties()
+			).collect(Collectors.toList());
+		} else {
+			children = this.generateChildrenNodes(
+				typeDefinition.getResolvedProperty(),
+				typeDefinition.getPropertyGenerator()
+					.generateChildProperties(typeDefinition.getResolvedProperty()),
+				this.nullInject,
+				traverseContext.withParentProperties()
+			);
+		}
+		this.children = children;
+		this.expandedTypeDefinition = typeDefinition;
+	}
+
 	@Override
 	public TraverseNodeMetadata getMetadata() {
 		return this;

fixture-monkey-api/src/main/java/com/navercorp/fixturemonkey/api/tree/TraverseNode.java

@@ -62,6 +62,23 @@ public interface TraverseNode {
 	 */
 	void forceExpand();
 
+	/**
+	 * expands the {@link TraverseNode} forcibly. In result, it always generates the child {@link TraverseNode}s.
+	 * It generates the child {@link TraverseNode}s by given {@link TypeDefinition}.
+	 * {@code Force} means that it expands as if it were a root node, even if it is not.
+	 * Unlike {@link #expand()}, it expands without metadata generated on expanding of the parent {@link TraverseNode}.
+	 * <p>
+	 * It will always append the {@link TraverseNode} nodes,
+	 * not remove already created nodes unless it is not a container.
+	 * The container's element nodes will shrink when the node is set by the fixed container object.
+	 * <p>
+	 * The leaf {@link TraverseNode} may generate child {@link TraverseNode}s.
+	 * For example, the {@link TraverseNode} with a self-reference.
+	 *
+	 * @param typeDefinition the {@link TypeDefinition} to expand forcibly
+	 */
+	void forceExpand(TypeDefinition typeDefinition);
+
 	/**
 	 * retrieves the metadata to traverse the tree. Some of its properties can be mutated during traversal.
 	 *

fixture-monkey/src/main/java/com/navercorp/fixturemonkey/tree/ObjectNode.java

@@ -89,6 +89,16 @@ public void forceExpand() {
 		);
 	}
 
+	@Override
+	public void forceExpand(TypeDefinition typeDefinition) {
+		this.traverseNode.forceExpand(typeDefinition);
+		this.setChildren(
+			nullSafe(this.traverseNode.getChildren()).asList().stream()
+				.map(it -> new ObjectNode(it, generateFixtureContext.newChildNodeContext()))
+				.collect(Collectors.toList())
+		);
+	}
+
 	@Override
 	public TraverseNodeMetadata getMetadata() {
 		return traverseNode.getMetadata();