From 2d2ebbb3eee0c7066af0fdaf1eed5ad62722dc0c Mon Sep 17 00:00:00 2001
From: waziqi89 <89210409+waziqi89@users.noreply.github.com>
Date: Fri, 2 Jun 2023 16:52:15 -0400
Subject: [PATCH] fix explain bug in multifunctionScorequery (#579)

---
 build.gradle                                  |  2 +-
 .../MultiFunctionScoreQuery.java              |  6 +-
 .../MultiFunctionScoreQueryTest.java          | 63 +++++++++++++++++++
 3 files changed, 67 insertions(+), 4 deletions(-)

diff --git a/build.gradle b/build.gradle
index 903ce600f..e5784c0f0 100644
--- a/build.gradle
+++ b/build.gradle
@@ -24,7 +24,7 @@ sourceCompatibility = 1.14
 targetCompatibility = 1.14
 
 allprojects {
-    version = '0.24.0'
+    version = '0.24.1'
     group = 'com.yelp.nrtsearch'
 }
 
diff --git a/src/main/java/com/yelp/nrtsearch/server/luceneserver/search/query/multifunction/MultiFunctionScoreQuery.java b/src/main/java/com/yelp/nrtsearch/server/luceneserver/search/query/multifunction/MultiFunctionScoreQuery.java
index dfd2d36b2..c8d76e88d 100644
--- a/src/main/java/com/yelp/nrtsearch/server/luceneserver/search/query/multifunction/MultiFunctionScoreQuery.java
+++ b/src/main/java/com/yelp/nrtsearch/server/luceneserver/search/query/multifunction/MultiFunctionScoreQuery.java
@@ -58,7 +58,7 @@ public class MultiFunctionScoreQuery extends Query {
   private final float minScore;
   private final boolean minExcluded;
 
-  private static boolean isFilteredByMinScore(
+  private static boolean hasPassedMinScore(
       float currentScore, float minimalScore, boolean minimalExcluded) {
     if (currentScore > minimalScore) {
       return true;
@@ -248,7 +248,7 @@ public Explanation explain(LeafReaderContext context, int doc) throws IOExceptio
         expl = explainBoost(expl, factorExplanation);
       }
       float curScore = expl.getValue().floatValue();
-      if (isFilteredByMinScore(curScore, minScore, minExcluded)) {
+      if (!hasPassedMinScore(curScore, minScore, minExcluded)) {
         expl =
             Explanation.noMatch(
                 "Score value is too low, expected at least "
@@ -372,7 +372,7 @@ public boolean matches() throws IOException {
           // we need to check the two-phase iterator first
           // otherwise calling score() is illegal
           curScore = in.score();
-          return isFilteredByMinScore(curScore, minScore, minExcluded);
+          return hasPassedMinScore(curScore, minScore, minExcluded);
         }
 
         @Override
diff --git a/src/test/java/com/yelp/nrtsearch/server/luceneserver/search/query/multifunction/MultiFunctionScoreQueryTest.java b/src/test/java/com/yelp/nrtsearch/server/luceneserver/search/query/multifunction/MultiFunctionScoreQueryTest.java
index 2e178af6a..6190d793f 100644
--- a/src/test/java/com/yelp/nrtsearch/server/luceneserver/search/query/multifunction/MultiFunctionScoreQueryTest.java
+++ b/src/test/java/com/yelp/nrtsearch/server/luceneserver/search/query/multifunction/MultiFunctionScoreQueryTest.java
@@ -772,6 +772,69 @@ public void testSingle_ScriptWith_0_Score_excluded() {
     verifyResponseHits(response, List.of(), List.of());
   }
 
+  @Test
+  public void test_noFunctions() {
+    SearchResponse response =
+        getGrpcServer()
+            .getBlockingStub()
+            .search(
+                SearchRequest.newBuilder()
+                    .setIndexName(DEFAULT_TEST_INDEX)
+                    .setStartHit(0)
+                    .setTopHits(10)
+                    .addRetrieveFields("doc_id")
+                    .addRetrieveFields("text_field")
+                    .setExplain(true)
+                    .setQuery(
+                        Query.newBuilder()
+                            .setMultiFunctionScoreQuery(
+                                MultiFunctionScoreQuery.newBuilder()
+                                    .setQuery(
+                                        Query.newBuilder()
+                                            .setMatchQuery(
+                                                MatchQuery.newBuilder()
+                                                    .setField("text_field")
+                                                    .setQuery("term1")
+                                                    .build())
+                                            .build())
+                                    .build())
+                            .build())
+                    .build());
+    verifyResponseHits(response, List.of(2, 4), List.of(0.33812057971954346, 0.27725890278816223));
+  }
+
+  @Test
+  public void test_noFunctions_withMinScore() {
+    SearchResponse response =
+        getGrpcServer()
+            .getBlockingStub()
+            .search(
+                SearchRequest.newBuilder()
+                    .setIndexName(DEFAULT_TEST_INDEX)
+                    .setStartHit(0)
+                    .setTopHits(10)
+                    .addRetrieveFields("doc_id")
+                    .addRetrieveFields("text_field")
+                    .setExplain(true)
+                    .setQuery(
+                        Query.newBuilder()
+                            .setMultiFunctionScoreQuery(
+                                MultiFunctionScoreQuery.newBuilder()
+                                    .setQuery(
+                                        Query.newBuilder()
+                                            .setMatchQuery(
+                                                MatchQuery.newBuilder()
+                                                    .setField("text_field")
+                                                    .setQuery("term1")
+                                                    .build())
+                                            .build())
+                                    .setMinScore(0.3f)
+                                    .build())
+                            .build())
+                    .build());
+    verifyResponseHits(response, List.of(2), List.of(0.33812057971954346));
+  }
+
   private void multiFunctionAndVerify(
       Query innerQuery,
       FunctionScoreMode scoreMode,