feat: VariationTree.assertConsistency

Author: ibbem

src/main/java/org/variantsync/diffdetective/variation/diff/DiffNode.java

@@ -742,6 +742,7 @@ public static DiffNode<DiffLinesLabel> fromID(int id, String label) {
      * Checks that the VariationDiff is in a valid state.
      * In particular, this method checks that all edges are well-formed (e.g., edges can be inconsistent because edges are double-linked).
      * This method also checks that a node with exactly one parent was edited, and that a node with exactly two parents was not edited.
+     * To check all children recursively, use {@link VariationDiff#assertConsistency}.
      * @see Assert#assertTrue
      * @throws AssertionError when an inconsistency is detected.
      */

src/main/java/org/variantsync/diffdetective/variation/tree/VariationNode.java

@@ -499,26 +499,28 @@ public VariationTreeNode<L> toVariationTree(final Map<? super T, VariationTreeNo
     }
 
     /**
-    * Checks that this node satisfies some easy to check invariants.
-    * In particular, this method checks that
-    * <ul>
-    * <li>if-chains are nested correctly,
-    * <li>the root is an {@link NodeType#IF} with the feature mapping {@code "true"},
-    * <li>the feature mapping is {@code null} iff {@code isConditionalAnnotation} is {@code false}
-    * and
-    * <li>all edges are well-formed (e.g., edges can be inconsistent because edges are
-    * double-linked).
-    * </ul>
-    *
-    * <p>Some invariants are not checked. These include
-    * <ul>
-    * <li>There should be no cycles and
-    * <li>{@link getID} should be unique in the whole variation tree.
-    * </ul>
-    *
-    * @see Assert#assertTrue
-    * @throws AssertionError when an inconsistency is detected.
-    */
+     * Checks that this node satisfies some easy to check invariants.
+     * In particular, this method checks that
+     * <ul>
+     * <li>if-chains are nested correctly,
+     * <li>the root is an {@link NodeType#IF} with the feature mapping {@code "true"},
+     * <li>the feature mapping is {@code null} iff {@code isConditionalAnnotation} is {@code false}
+     * and
+     * <li>all edges are well-formed (e.g., edges can be inconsistent because edges are
+     * double-linked).
+     * </ul>
+     *
+     * <p>Some invariants are not checked. These include
+     * <ul>
+     * <li>There should be no cycles,
+     * <li>{@link getID} should be unique in the whole variation tree, and
+     * <li>children are not checked recursively.
+     * </ul>
+     * Use {@link VariationTree#assertConsistency} to check all children recursively.
+     *
+     * @see Assert#assertTrue
+     * @throws AssertionError when an inconsistency is detected.
+     */
     public void assertConsistency() {
         // ELSE and ELIF nodes have an IF or ELIF as parent.
         if (isElse() || isElif()) {

src/main/java/org/variantsync/diffdetective/variation/tree/VariationTree.java

@@ -5,6 +5,7 @@
 import org.variantsync.diffdetective.util.Assert;
 import org.variantsync.diffdetective.variation.DiffLinesLabel;
 import org.variantsync.diffdetective.variation.Label;
+import org.variantsync.diffdetective.variation.NodeType; // For Javadoc
 import org.variantsync.diffdetective.variation.diff.DiffNode;
 import org.variantsync.diffdetective.variation.diff.VariationDiff;
 import org.variantsync.diffdetective.variation.diff.Projection;
@@ -223,6 +224,17 @@ public String unparse() {
         return result.toString();
     }
 
+    /**
+     * Checks whether this {@link VariationTree} is consistent.
+     * Throws an error if this {@link VariationTree} is inconsistent (e.g., if there are multiple
+     * {@link NodeType#ELSE} nodes). Has no side-effects otherwise.
+     *
+     * @see VariationNode#assertConsistency
+     */
+    public void assertConsistency() {
+        forAllPreorder(VariationTreeNode::assertConsistency);
+    }
+
     @Override
     public String toString() {
         return "variation tree from " + source;