Remove setNextScore in SearchScript

Due to a change in elasticsearch 1.4.0, we need to apply a similar patch here.

See #6864
See #7819

Closes #16.
Closes #21.

Author: brwe

src/main/java/org/elasticsearch/script/python/PythonScriptEngineService.java

@@ -26,6 +26,7 @@
 import org.elasticsearch.common.inject.Inject;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.script.ExecutableScript;
+import org.elasticsearch.script.ScoreAccessor;
 import org.elasticsearch.script.ScriptEngineService;
 import org.elasticsearch.script.SearchScript;
 import org.elasticsearch.search.lookup.SearchLookup;
@@ -164,7 +165,7 @@ public PythonSearchScript(PyCode code, Map<String, Object> vars, SearchLookup lo
 
         @Override
         public void setScorer(Scorer scorer) {
-            lookup.setScorer(scorer);
+            pyVars.__setitem__("_score", Py.java2py(new ScoreAccessor(scorer)));
         }
 
         @Override

src/test/java/org/elasticsearch/script/python/PythonScriptSearchTests.java

@@ -26,12 +26,15 @@
 import org.elasticsearch.index.query.functionscore.ScoreFunctionBuilders;
 import org.elasticsearch.plugins.PluginsService;
 import org.elasticsearch.script.ScriptService;
+import org.elasticsearch.search.aggregations.bucket.terms.Terms;
 import org.elasticsearch.search.sort.SortOrder;
 import org.elasticsearch.test.ElasticsearchIntegrationTest;
 import org.hamcrest.CoreMatchers;
+import org.hamcrest.Matchers;
 import org.junit.After;
 import org.junit.Test;
 
+import java.io.IOException;
 import java.util.Arrays;
 import java.util.List;
 import java.util.Map;
@@ -40,7 +43,10 @@
 import static org.elasticsearch.common.xcontent.XContentFactory.jsonBuilder;
 import static org.elasticsearch.index.query.FilterBuilders.scriptFilter;
 import static org.elasticsearch.index.query.QueryBuilders.*;
+import static org.elasticsearch.index.query.functionscore.ScoreFunctionBuilders.scriptFunction;
+import static org.elasticsearch.search.aggregations.AggregationBuilders.terms;
 import static org.elasticsearch.search.builder.SearchSourceBuilder.searchSource;
+import static org.elasticsearch.test.hamcrest.ElasticsearchAssertions.assertSearchResponse;
 import static org.hamcrest.CoreMatchers.is;
 import static org.hamcrest.Matchers.equalTo;
 
@@ -193,7 +199,7 @@ public void testCustomScriptBoost() throws Exception {
         response = client().search(searchRequest()
                 .searchType(SearchType.QUERY_THEN_FETCH)
                 .source(searchSource().explain(true).query(functionScoreQuery(termQuery("test", "value"))
-                        .add(ScoreFunctionBuilders.scriptFunction("doc['num1'].value * _score").lang("python"))))
+                        .add(ScoreFunctionBuilders.scriptFunction("doc['num1'].value * _score.doubleValue()").lang("python"))))
         ).actionGet();
 
         assertThat("Failures " + Arrays.toString(response.getShardFailures()), response.getShardFailures().length, equalTo(0));
@@ -208,7 +214,7 @@ public void testCustomScriptBoost() throws Exception {
         response = client().search(searchRequest()
                 .searchType(SearchType.QUERY_THEN_FETCH)
                 .source(searchSource().explain(true).query(functionScoreQuery(termQuery("test", "value"))
-                        .add(ScoreFunctionBuilders.scriptFunction("param1 * param2 * _score").param("param1", 2).param("param2", 2).lang("python"))))
+                        .add(ScoreFunctionBuilders.scriptFunction("param1 * param2 * _score.doubleValue()").param("param1", 2).param("param2", 2).lang("python"))))
         ).actionGet();
 
         assertThat("Failures " + Arrays.toString(response.getShardFailures()), response.getShardFailures().length, equalTo(0));
@@ -239,4 +245,47 @@ public void testPythonEmptyParameters() throws Exception {
 
         assertThat((String) value, CoreMatchers.equalTo("bar"));
     }
+
+    @Test
+    public void testScriptScoresNested() throws IOException {
+        createIndex("index");
+        ensureYellow();
+        index("index", "testtype", "1", jsonBuilder().startObject().field("dummy_field", 1).endObject());
+        refresh();
+        SearchResponse response = client().search(
+                searchRequest().source(
+                        searchSource().query(
+                                functionScoreQuery(
+                                        functionScoreQuery(
+                                                functionScoreQuery().add(scriptFunction("1").lang("python")))
+                                                .add(scriptFunction("_score.doubleValue()").lang("python")))
+                                        .add(scriptFunction("_score.doubleValue()").lang("python")
+                                        )
+                        )
+                )
+        ).actionGet();
+        assertSearchResponse(response);
+        assertThat(response.getHits().getAt(0).score(), equalTo(1.0f));
+    }
+
+    @Test
+    public void testScriptScoresWithAgg() throws IOException {
+        createIndex("index");
+        ensureYellow();
+        index("index", "testtype", "1", jsonBuilder().startObject().field("dummy_field", 1).endObject());
+        refresh();
+        SearchResponse response = client().search(
+                searchRequest().source(
+                        searchSource().query(
+                                functionScoreQuery()
+                                        .add(scriptFunction("_score.doubleValue()").lang("python")
+                                        )
+                        ).aggregation(terms("score_agg").script("_score.doubleValue()").lang("python"))
+                )
+        ).actionGet();
+        assertSearchResponse(response);
+        assertThat(response.getHits().getAt(0).score(), equalTo(1.0f));
+        assertThat(((Terms) response.getAggregations().asMap().get("score_agg")).getBuckets().get(0).getKeyAsNumber().floatValue(), Matchers.is(1f));
+        assertThat(((Terms) response.getAggregations().asMap().get("score_agg")).getBuckets().get(0).getDocCount(), Matchers.is(1l));
+    }
 }