Brings back Scorer#applyAsRequiredClause

lucene/core/src/java/org/apache/lucene/search/BlockMaxConjunctionBulkScorer.java

@@ -187,7 +187,7 @@ private void scoreWindowScoreFirst(
               docAndScoreAccBuffer, sumOfOtherClause, scorable.minCompetitiveScore, scorers.length);
         }
 
-        ScorerUtil.applyRequiredClause(docAndScoreAccBuffer, iterators[i], scorables[i]);
+        scorers[i].applyAsRequiredClause(docAndScoreAccBuffer);
       }
 
       for (int i = 0; i < docAndScoreAccBuffer.size; ++i) {

lucene/core/src/java/org/apache/lucene/search/ConstantScoreScorer.java

@@ -163,4 +163,28 @@ public void nextDocsAndScores(int upTo, Bits liveDocs, DocAndFloatFeatureBuffer
     Arrays.fill(buffer.features, 0, size, score);
     buffer.size = size;
   }
+
+  @Override
+  public void applyAsRequiredClause(DocAndScoreAccBuffer buffer) throws IOException {
+    int intersectionSize = 0;
+    int curDoc = disi.docID();
+    for (int i = 0; i < buffer.size; ++i) {
+      int targetDoc = buffer.docs[i];
+      if (curDoc < targetDoc) {
+        curDoc = disi.advance(targetDoc);
+      }
+      if (curDoc == targetDoc) {
+        buffer.docs[intersectionSize] = targetDoc;
+        buffer.scores[intersectionSize] = buffer.scores[i];
+        intersectionSize++;
+      }
+    }
+
+    buffer.size = intersectionSize;
+    if (score != 0) {
+      for (int i = 0; i < intersectionSize; ++i) {
+        buffer.scores[i] += score;
+      }
+    }
+  }
 }

lucene/core/src/java/org/apache/lucene/search/MaxScoreBulkScorer.java

@@ -262,8 +262,7 @@ private void scoreInnerWindowAsConjunction(LeafCollector collector, Bits acceptD
               allScorers.length);
         }
 
-        DisiWrapper scorer = allScorers[i];
-        ScorerUtil.applyRequiredClause(docAndScoreAccBuffer, scorer.iterator, scorer.scorable);
+        allScorers[i].scorer.applyAsRequiredClause(docAndScoreAccBuffer);
       }
 
       scoreNonEssentialClauses(collector, docAndScoreAccBuffer, firstRequiredScorer);

lucene/core/src/java/org/apache/lucene/search/Scorer.java

@@ -130,4 +130,27 @@ public void nextDocsAndScores(int upTo, Bits liveDocs, DocAndFloatFeatureBuffer
     }
     buffer.size = size;
   }
+
+  /**
+   * Apply this {@link Scorer} as a required clause on the given {@link DocAndScoreAccBuffer}. This
+   * filters out documents from the buffer that do not match this scorer, and adds the scores of
+   * this {@link Scorer} to the scores.
+   */
+  public void applyAsRequiredClause(DocAndScoreAccBuffer buffer) throws IOException {
+    DocIdSetIterator iterator = iterator();
+    int intersectionSize = 0;
+    int curDoc = iterator.docID();
+    for (int i = 0; i < buffer.size; ++i) {
+      int targetDoc = buffer.docs[i];
+      if (curDoc < targetDoc) {
+        curDoc = iterator.advance(targetDoc);
+      }
+      if (curDoc == targetDoc) {
+        buffer.docs[intersectionSize] = targetDoc;
+        buffer.scores[intersectionSize] = buffer.scores[i] + score();
+        intersectionSize++;
+      }
+    }
+    buffer.size = intersectionSize;
+  }
 }

lucene/core/src/java/org/apache/lucene/search/TermScorer.java

@@ -26,6 +26,7 @@
 import org.apache.lucene.search.similarities.Similarity.SimScorer;
 import org.apache.lucene.util.ArrayUtil;
 import org.apache.lucene.util.Bits;
+import org.apache.lucene.util.IntsRef;
 import org.apache.lucene.util.LongsRef;
 
 /**
@@ -41,6 +42,7 @@ public final class TermScorer extends Scorer {
   private final NumericDocValues norms;
   private final ImpactsDISI impactsDisi;
   private final MaxScoreCache maxScoreCache;
+  private int[] freqs = IntsRef.EMPTY_INTS;
   private long[] normValues = LongsRef.EMPTY_LONGS;
 
   /** Construct a {@link TermScorer} that will iterate all documents. */
@@ -171,4 +173,41 @@ public void nextDocsAndScores(int upTo, Bits liveDocs, DocAndFloatFeatureBuffer
 
     bulkScorer.score(buffer.size, buffer.features, normValues, buffer.features);
   }
+
+  @Override
+  public void applyAsRequiredClause(DocAndScoreAccBuffer buffer) throws IOException {
+    int size = buffer.size;
+    if (freqs.length < size) {
+      freqs = ArrayUtil.growNoCopy(freqs, size);
+      normValues = new long[freqs.length];
+    }
+
+    int intersectionSize = 0;
+    int curDoc = docID();
+    for (int i = 0; i < size; i++) {
+      int targetDoc = buffer.docs[i];
+      if (curDoc < targetDoc) {
+        curDoc = postingsEnum.advance(targetDoc);
+      }
+      if (curDoc == targetDoc) {
+        buffer.docs[intersectionSize] = targetDoc;
+        buffer.scores[intersectionSize] = buffer.scores[i];
+        freqs[intersectionSize] = postingsEnum.freq();
+        intersectionSize++;
+      }
+    }
+    buffer.size = intersectionSize;
+
+    for (int i = 0; i < intersectionSize; i++) {
+      if (norms == null || norms.advanceExact(buffer.docs[i]) == false) {
+        normValues[i] = 1L;
+      } else {
+        normValues[i] = norms.longValue();
+      }
+    }
+
+    for (int i = 0; i < intersectionSize; i++) {
+      buffer.scores[i] += scorer.score(freqs[i], normValues[i]);
+    }
+  }
 }