Fix PhaseModificationInNamespacePath effects

[yangtools.git] / yang / yang-parser-reactor / src / main / java / org / opendaylight / yangtools / yang / parser / stmt / reactor / ModifierImpl.java

diff --git a/yang/yang-parser-reactor/src/main/java/org/opendaylight/yangtools/yang/parser/stmt/reactor/ModifierImpl.java b/yang/yang-parser-reactor/src/main/java/org/opendaylight/yangtools/yang/parser/stmt/reactor/ModifierImpl.java
index f3b62c2db13a016c667f011b02932626f1d99435..7327e988af32d362801e90586d423ecb8fa8200a 100644 (file)
--- a/yang/yang-parser-reactor/src/main/java/org/opendaylight/yangtools/yang/parser/stmt/reactor/ModifierImpl.java
+++ b/yang/yang-parser-reactor/src/main/java/org/opendaylight/yangtools/yang/parser/stmt/reactor/ModifierImpl.java
@@ -382,6 +382,11 @@ final class ModifierImpl implements ModelActionBuilder {
         }
     }
 
+    /**
+     * This similar to {@link PhaseModificationInNamespace}, but allows recursive descent until it finds the real
+     * target. The mechanics is driven as a sequence of prerequisites along a path: first we hook onto namespace to
+     * give us the first step. When it does, we hook onto the first item to provide us the second step and so on.
+     */
     private final class PhaseModificationInNamespacePath<C extends Mutable<?, ?, ?>, K,
             N extends IdentifierNamespace<K, ? extends StmtContext<?, ?, ?>>> extends AbstractPrerequisite<C>
             implements OnNamespaceItemAdded, ContextMutation {
@@ -413,15 +418,27 @@ final class ModifierImpl implements ModelActionBuilder {
                 return;
             }
 
+            // Hook onto target: we either have a modification of the target itself or one of its children.
+            target.addMutation(modPhase, this);
+            // We have completed the context -> target step, hence we are no longer directly blocking context from
+            // making forward progress.
+            context.removeMutation(modPhase, this);
+
             if (!it.hasNext()) {
-                target.addMutation(modPhase, this);
+                // Last step: we are done
                 resolvePrereq((C) value);
                 return;
             }
 
+            // Make sure target's storage notifies us when the next step becomes available.
             hookOnto(target, namespace, it.next());
         }
 
+        @Override
+        ToStringHelper addToStringAttributes(final ToStringHelper toStringHelper) {
+            return super.addToStringAttributes(toStringHelper).add("phase", modPhase).add("keys", keys);
+        }
+
         void hookOnto(final StmtContext<?, ?, ?> context, final Class<?> namespace) {
             checkArgument(it.hasNext(), "Namespace %s keys may not be empty", namespace);
             hookOnto(contextImpl(context), namespace, it.next());