Make QueryEnvironment#getTargetsMatchingPattern pass its result to a callback.

This is the third step in a series to allow processing large sets of targets in query target patterns via streaming batches rather than all at once. This should also be a functional no-op.

--
MOS_MIGRATED_REVID=111620668

5 files changed, 21 insertions, 10 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/query2/AbstractBlazeQueryEnvironment.java b/src/main/java/com/google/devtools/build/lib/query2/AbstractBlazeQueryEnvironment.java
index beba2f3ee8..c63e00dd37 100644
--- a/src/main/java/com/google/devtools/build/lib/query2/AbstractBlazeQueryEnvironment.java
+++ b/src/main/java/com/google/devtools/build/lib/query2/AbstractBlazeQueryEnvironment.java
@@ -35,6 +35,7 @@ import com.google.devtools.build.lib.query2.engine.QueryEnvironment;
 import com.google.devtools.build.lib.query2.engine.QueryEvalResult;
 import com.google.devtools.build.lib.query2.engine.QueryException;
 import com.google.devtools.build.lib.query2.engine.QueryExpression;
+import com.google.devtools.build.lib.query2.engine.QueryUtil.AggregateAllCallback;
 import com.google.devtools.build.lib.util.BinaryPredicate;
 import com.google.devtools.build.lib.util.Preconditions;
 import com.google.devtools.build.skyframe.WalkableGraph.WalkableGraphFactory;
@@ -233,7 +234,9 @@ public abstract class AbstractBlazeQueryEnvironment<T> implements QueryEnvironme
         reportBuildFileError(caller, e.getMessage());
       }
     }
-    return getTargetsMatchingPattern(caller, pattern);
+    AggregateAllCallback<T> aggregatingCallback = new AggregateAllCallback<>();
+    getTargetsMatchingPattern(caller, pattern, aggregatingCallback);
+    return aggregatingCallback.getResult();
   }
 
   protected abstract Map<String, Set<Target>> preloadOrThrow(
diff --git a/src/main/java/com/google/devtools/build/lib/query2/BlazeQueryEnvironment.java b/src/main/java/com/google/devtools/build/lib/query2/BlazeQueryEnvironment.java
index d4614f0cbf..2f889aeb32 100644
--- a/src/main/java/com/google/devtools/build/lib/query2/BlazeQueryEnvironment.java
+++ b/src/main/java/com/google/devtools/build/lib/query2/BlazeQueryEnvironment.java
@@ -124,8 +124,8 @@ public class BlazeQueryEnvironment extends AbstractBlazeQueryEnvironment<Target>
   }
 
   @Override
-  public Set<Target> getTargetsMatchingPattern(QueryExpression caller,
-      String pattern) throws QueryException {
+  public void getTargetsMatchingPattern(
+      QueryExpression caller, String pattern, Callback<Target> callback) throws QueryException {
     // We can safely ignore the boolean error flag. The evaluateQuery() method above wraps the
     // entire query computation in an error sensor.
 
@@ -180,7 +180,11 @@ public class BlazeQueryEnvironment extends AbstractBlazeQueryEnvironment<Target>
         }
       }
     }
-    return result;
+    try {
+      callback.process(result);
+    } catch (InterruptedException e) {
+      throw new QueryException(caller, e.getMessage());
+    }
   }
 
   @Override
diff --git a/src/main/java/com/google/devtools/build/lib/query2/SkyQueryEnvironment.java b/src/main/java/com/google/devtools/build/lib/query2/SkyQueryEnvironment.java
index 614f502087..749a563529 100644
--- a/src/main/java/com/google/devtools/build/lib/query2/SkyQueryEnvironment.java
+++ b/src/main/java/com/google/devtools/build/lib/query2/SkyQueryEnvironment.java
@@ -324,8 +324,8 @@ public class SkyQueryEnvironment extends AbstractBlazeQueryEnvironment<Target> {
   }
 
   @Override
-  public Set<Target> getTargetsMatchingPattern(QueryExpression owner, String pattern)
-      throws QueryException {
+  public void getTargetsMatchingPattern(
+      QueryExpression owner, String pattern, Callback<Target> callback) throws QueryException {
     Set<Target> targets = new LinkedHashSet<>(resolvedTargetPatterns.get(pattern));
 
     // Sets.filter would be more convenient here, but can't deal with exceptions.
@@ -336,7 +336,11 @@ public class SkyQueryEnvironment extends AbstractBlazeQueryEnvironment<Target> {
         targetIterator.remove();
       }
     }
-    return targets;
+    try {
+      callback.process(targets);
+    } catch (InterruptedException e) {
+      throw new QueryException(owner, e.getMessage());
+    }
   }
 
   @Override
diff --git a/src/main/java/com/google/devtools/build/lib/query2/engine/QueryEnvironment.java b/src/main/java/com/google/devtools/build/lib/query2/engine/QueryEnvironment.java
index 13d7f4ca12..0ebf71139c 100644
--- a/src/main/java/com/google/devtools/build/lib/query2/engine/QueryEnvironment.java
+++ b/src/main/java/com/google/devtools/build/lib/query2/engine/QueryEnvironment.java
@@ -135,10 +135,10 @@ public interface QueryEnvironment<T> {
   }
 
   /**
-   * Returns the set of target nodes in the graph for the specified target
+   * Invokes {@code callback} with the set of target nodes in the graph for the specified target
    * pattern, in 'blaze build' syntax.
    */
-  Set<T> getTargetsMatchingPattern(QueryExpression owner, String pattern)
+  void getTargetsMatchingPattern(QueryExpression owner, String pattern, Callback<T> callback)
       throws QueryException;
 
   /** Ensures the specified target exists. */
diff --git a/src/main/java/com/google/devtools/build/lib/query2/engine/TargetLiteral.java b/src/main/java/com/google/devtools/build/lib/query2/engine/TargetLiteral.java
index c46d193f63..32eca663eb 100644
--- a/src/main/java/com/google/devtools/build/lib/query2/engine/TargetLiteral.java
+++ b/src/main/java/com/google/devtools/build/lib/query2/engine/TargetLiteral.java
@@ -51,7 +51,7 @@ final class TargetLiteral extends QueryExpression {
       }
       callback.process(value);
     } else {
-      callback.process(env.getTargetsMatchingPattern(this, pattern));
+      env.getTargetsMatchingPattern(this, pattern, callback);
     }
   }