simple query string: remove (not working) support for alternate formats

Removed attempt of parsing of `field` rather than `fields` and attempted support of the following syntax:

```
{
  "simple_query_string": {
    "body" : {
      "query": "foo bar"
    }
  }
}
```

Both these two syntaxes were undocumented, untested and not working.

Added test for case when `fields` is not specified, then the default field is queried.

Closes #12794
Closes #12798

core/src/main/java/org/elasticsearch/index/query/SimpleQueryStringParser.java

@@ -27,10 +27,8 @@
 import org.elasticsearch.common.inject.Inject;
 import org.elasticsearch.common.lucene.search.Queries;
 import org.elasticsearch.common.regex.Regex;
-import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.util.LocaleUtils;
 import org.elasticsearch.common.xcontent.XContentParser;
-import org.elasticsearch.index.mapper.FieldMapper;
 import org.elasticsearch.index.mapper.MappedFieldType;
 
 import java.io.IOException;
@@ -55,7 +53,7 @@
  * <li>'{@code ~}N' at the end of phrases specifies near/slop query: <tt>"term1 term2"~5</tt>
  * </ul>
  * <p/>
- * See: {@link XSimpleQueryParser} for more information.
+ * See: {@link SimpleQueryParser} for more information.
  * <p/>
  * This query supports these options:
  * <p/>
@@ -75,7 +73,7 @@ public class SimpleQueryStringParser implements QueryParser {
     public static final String NAME = "simple_query_string";
 
     @Inject
-    public SimpleQueryStringParser(Settings settings) {
+    public SimpleQueryStringParser() {
 
     }
 
@@ -92,7 +90,6 @@ public Query parse(QueryParseContext parseContext) throws IOException, QueryPars
         String queryBody = null;
         float boost = 1.0f; 
         String queryName = null;
-        String field = null;
         String minimumShouldMatch = null;
         Map<String, Float> fieldsAndWeights = null;
         BooleanClause.Occur defaultOperator = null;
@@ -141,9 +138,7 @@ public Query parse(QueryParseContext parseContext) throws IOException, QueryPars
                         }
                     }
                 } else {
-                    throw new QueryParsingException(parseContext,
- "[" + NAME + "] query does not support [" + currentFieldName
- + "]");
+                    throw new QueryParsingException(parseContext, "[" + NAME + "] query does not support [" + currentFieldName + "]");
                 }
             } else if (token.isValue()) {
                 if ("query".equals(currentFieldName)) {
@@ -155,8 +150,6 @@ public Query parse(QueryParseContext parseContext) throws IOException, QueryPars
                     if (analyzer == null) {
                         throw new QueryParsingException(parseContext, "[" + NAME + "] analyzer [" + parser.text() + "] not found");
                     }
-                } else if ("field".equals(currentFieldName)) {
-                    field = parser.text();
                 } else if ("default_operator".equals(currentFieldName) || "defaultOperator".equals(currentFieldName)) {
                     String op = parser.text();
                     if ("or".equalsIgnoreCase(op)) {
@@ -201,24 +194,14 @@ public Query parse(QueryParseContext parseContext) throws IOException, QueryPars
         if (queryBody == null) {
             throw new QueryParsingException(parseContext, "[" + NAME + "] query text missing");
         }
-
-        // Support specifying only a field instead of a map
-        if (field == null) {
-            field = currentFieldName;
-        }
-
-        // Use the default field (_all) if no fields specified
-        if (fieldsAndWeights == null) {
-            field = parseContext.defaultField();
-        }
 
         // Use standard analyzer by default
         if (analyzer == null) {
             analyzer = parseContext.mapperService().searchAnalyzer();
         }
 
         if (fieldsAndWeights == null) {
-            fieldsAndWeights = Collections.singletonMap(field, 1.0F);
+            fieldsAndWeights = Collections.singletonMap(parseContext.defaultField(), 1.0F);
         }
         SimpleQueryParser sqp = new SimpleQueryParser(analyzer, fieldsAndWeights, flags, sqsSettings);
 

core/src/test/java/org/elasticsearch/index/query/SimpleIndexQueryParserTests.java

@@ -21,7 +21,6 @@
 
 import com.google.common.collect.Lists;
 import com.google.common.collect.Sets;
-
 import org.apache.lucene.analysis.core.WhitespaceAnalyzer;
 import org.apache.lucene.index.*;
 import org.apache.lucene.index.memory.MemoryIndex;
@@ -39,6 +38,7 @@
 import org.apache.lucene.util.NumericUtils;
 import org.apache.lucene.util.automaton.TooComplexToDeterminizeException;
 import org.elasticsearch.action.termvectors.*;
+import org.elasticsearch.cluster.metadata.MetaData;
 import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.bytes.BytesArray;
 import org.elasticsearch.common.compress.CompressedXContent;
@@ -73,11 +73,12 @@
 import java.util.Arrays;
 import java.util.EnumSet;
 import java.util.List;
+import java.util.Locale;
 
-import static org.elasticsearch.test.StreamsUtils.copyToBytesFromClasspath;
-import static org.elasticsearch.test.StreamsUtils.copyToStringFromClasspath;
 import static org.elasticsearch.common.xcontent.XContentFactory.jsonBuilder;
 import static org.elasticsearch.index.query.QueryBuilders.*;
+import static org.elasticsearch.test.StreamsUtils.copyToBytesFromClasspath;
+import static org.elasticsearch.test.StreamsUtils.copyToStringFromClasspath;
 import static org.elasticsearch.test.hamcrest.ElasticsearchAssertions.assertBooleanSubQuery;
 import static org.hamcrest.Matchers.*;
 
@@ -2379,7 +2380,7 @@ public void testProperErrorMessagesForMisplacedWeightsAndFunctions() throws IOEx
         IndexQueryParserService queryParser = queryParser();
         String query = jsonBuilder().startObject().startObject("function_score")
                 .startArray("functions")
-                .startObject().field("weight", 2).field("boost_factor",2).endObject()
+                .startObject().field("weight", 2).field("boost_factor", 2).endObject()
                 .endArray()
                 .endObject().endObject().string();
         try {
@@ -2480,4 +2481,19 @@ public void testBlendedRewriteMethod() throws IOException {
             assertThat(prefixQuery.getRewriteMethod(), instanceOf(MultiTermQuery.TopTermsBlendedFreqScoringRewrite.class));
         }
     }
+
+    @Test
+    public void testSimpleQueryStringNoFields() throws Exception {
+        IndexQueryParserService queryParser = queryParser();
+        String queryText = randomAsciiOfLengthBetween(1, 10).toLowerCase(Locale.ROOT);
+        String query = "{\n" +
+                "    \"simple_query_string\" : {\n" +
+                "        \"query\" : \"" + queryText + "\"\n" +
+                "    }\n" +
+                "}";
+        Query parsedQuery = queryParser.parse(query).query();
+        assertThat(parsedQuery, instanceOf(TermQuery.class));
+        TermQuery termQuery = (TermQuery) parsedQuery;
+        assertThat(termQuery.getTerm(), equalTo(new Term(MetaData.ALL, queryText)));
+    }
 }

core/src/test/java/org/elasticsearch/search/query/SimpleQueryStringIT.java

@@ -93,11 +93,6 @@ public void testSimpleQueryString() throws ExecutionException, InterruptedExcept
         searchResponse = client().prepareSearch().setQuery(simpleQueryStringQuery("spaghetti").field("*body")).get();
         assertHitCount(searchResponse, 2l);
         assertSearchHits(searchResponse, "5", "6");
-
-        // Have to bypass the builder here because the builder always uses "fields" instead of "field"
-        searchResponse = client().prepareSearch().setQuery("{\"simple_query_string\": {\"query\": \"spaghetti\", \"field\": \"_all\"}}").get();
-        assertHitCount(searchResponse, 2l);
-        assertSearchHits(searchResponse, "5", "6");
     }
 
     @Test