Misc cleanups to TopScoreDocCollector

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

@@ -62,24 +62,22 @@ public final class HitQueue extends PriorityQueue<ScoreDoc> {
   public HitQueue(int size, boolean prePopulate) {
     super(
         size,
-        () -> {
-          if (prePopulate) {
-            // Always set the doc Id to MAX_VALUE so that it won't be favored by
-            // lessThan. This generally should not happen since if score is not NEG_INF,
-            // TopScoreDocCollector will always add the object to the queue.
-            return new ScoreDoc(Integer.MAX_VALUE, Float.NEGATIVE_INFINITY);
-          } else {
-            return null;
-          }
-        });
+        prePopulate
+            ? () -> {
+              // Always set the doc Id to MAX_VALUE so that it won't be favored by
+              // lessThan. This generally should not happen since if score is not NEG_INF,
+              // TopScoreDocCollector will always add the object to the queue.
+              return new ScoreDoc(Integer.MAX_VALUE, Float.NEGATIVE_INFINITY);
+            }
+            : () -> null);
   }
 
   @Override
   protected final boolean lessThan(ScoreDoc hitA, ScoreDoc hitB) {
-    if (hitA.score == hitB.score) {
+    int cmp = Float.compare(hitA.score, hitB.score);
+    if (cmp == 0) {
       return hitA.doc > hitB.doc;
-    } else {
-      return hitA.score < hitB.score;
     }
+    return cmp < 0;
   }
 }

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

@@ -87,7 +87,7 @@ protected int topDocsSize() {
     // In case pq was populated with sentinel values, there might be less
     // results than pq.size(). Therefore return all results until either
     // pq.size() or totalHits.
-    return totalHits < pq.size() ? totalHits : pq.size();
+    return Math.min(totalHits, pq.size());
   }
 
   /** Returns the top docs that were collected by this collector. */

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

@@ -117,7 +117,7 @@ static class PagingTopScoreDocCollector extends TopScoreDocCollector {
 
     @Override
     protected int topDocsSize() {
-      return collectedHits < pq.size() ? collectedHits : pq.size();
+      return Math.min(collectedHits, pq.size());
     }
 
     @Override
@@ -158,26 +158,18 @@ public void collect(int doc) throws IOException {
             updateGlobalMinCompetitiveScore(scorer);
           }
 
-          if (score > after.score || (score == after.score && doc <= afterDoc)) {
-            // hit was collected on a previous page
-            if (totalHitsRelation == TotalHits.Relation.EQUAL_TO) {
-              // we just reached totalHitsThreshold, we can start setting the min
-              // competitive score now
-              updateMinCompetitiveScore(scorer);
-            }
-            return;
-          }
-
-          if (score <= pqTop.score) {
+          if (score > after.score
+              || (score == after.score && doc <= afterDoc)
+              || score <= pqTop.score) {
+            // Either hit was collected on a previous page or
+            // since docs are returned in-order (i.e., increasing doc Id), a document
+            // with equal score to pqTop.score cannot compete since HitQueue favors
+            // documents with lower doc Ids. Therefore reject those docs too.
             if (totalHitsRelation == TotalHits.Relation.EQUAL_TO) {
               // we just reached totalHitsThreshold, we can start setting the min
               // competitive score now
               updateMinCompetitiveScore(scorer);
             }
-
-            // Since docs are returned in-order (i.e., increasing doc Id), a document
-            // with equal score to pqTop.score cannot compete since HitQueue favors
-            // documents with lower doc Ids. Therefore reject those docs too.
             return;
           }
           collectedHits++;