Change the description of NodeEntry#markDirty to better align with the InMemoryNodeEntry#markDirty implementation.

--
MOS_MIGRATED_REVID=95758779

1 files changed, 7 insertions, 1 deletions

diff --git a/src/main/java/com/google/devtools/build/skyframe/NodeEntry.java b/src/main/java/com/google/devtools/build/skyframe/NodeEntry.java
index 08ec80446e..1905657177 100644
--- a/src/main/java/com/google/devtools/build/skyframe/NodeEntry.java
+++ b/src/main/java/com/google/devtools/build/skyframe/NodeEntry.java
@@ -217,10 +217,16 @@ public interface NodeEntry {
   boolean isChanged();
 
   /**
-   * Marks this node dirty, or changed if {@code isChanged} is true. The node  is put in the
+   * Marks this node dirty, or changed if {@code isChanged} is true. The node is put in the
    * just-created state. It will be re-evaluated if necessary during the evaluation phase,
    * but if it has not changed, it will not force a re-evaluation of its parents.
    *
+   * <p>{@code markDirty(b)} must not be called on an undone node if {@code isChanged() == b}.
+   * It is the caller's responsibility to ensure that this does not happen.  Calling
+   * {@code markDirty(false)} when {@code isChanged() == true} has no effect. The idea here is that
+   * the caller will only ever want to call {@code markDirty()} a second time if a transition from a
+   * dirty-unchanged state to a dirty-changed state is required.
+   *
    * @return The direct deps and value of this entry, or null if the entry has already been marked
    * dirty. In the latter case, the caller should abort its handling of this node, since another
    * thread is already dealing with it.