Reverted changes to keyword field mapper

Author: Kubik42

server/src/main/java/org/elasticsearch/index/mapper/KeywordFieldMapper.java

@@ -1221,6 +1221,14 @@ private boolean indexValue(DocumentParserContext context, String value) {
         return indexValue(context, new Text(value));
     }
 
+    /**
+     * Returns whether this field should be stored separately as a {@link StoredField} for supporting synthetic source.
+     */
+    private boolean storeIgnoredValuesForSyntheticSource() {
+        // skip all fields that are multi-fields
+        return fieldType().isSyntheticSourceEnabled && fieldType().isWithinMultiField == false;
+    }
+
     private boolean indexValue(DocumentParserContext context, XContentString value) {
         // nothing to index
         if (value == null) {
@@ -1232,17 +1240,18 @@ private boolean indexValue(DocumentParserContext context, XContentString value)
             return false;
         }
 
-        // if the value's length exceeds ignore_above, then don't index it. Instead, store it in ignored source
-        // that being said, don't store multi fields in ignored source as thats the responsibility of the parent
-        if (value.stringLength() > fieldType().ignoreAbove() && isWithinMultiField == false) {
+        // if the value's length exceeds ignore_above, then don't index it
+        if (value.stringLength() > fieldType().ignoreAbove()) {
             context.addIgnoredField(fullPath());
-            // unless synthetic source is enabled, then store a copy of the value so that synthetic source be load it
-            if (fieldType().isSyntheticSourceEnabled) {
+
+            // if synthetic source is enabled, then store a copy of the value so that synthetic source be load it
+            if (storeIgnoredValuesForSyntheticSource()) {
                 var utfBytes = value.bytes();
                 var bytesRef = new BytesRef(utfBytes.bytes(), utfBytes.offset(), utfBytes.length());
                 final String fieldName = fieldType().syntheticSourceFallbackFieldName();
                 context.doc().add(new StoredField(fieldName, bytesRef));
             }
+
             return false;
         }
 

server/src/test/java/org/elasticsearch/index/mapper/TextFieldMapperTests.java

@@ -311,7 +311,7 @@ public void testStoreParameterDefaults() throws IOException {
         }
     }
 
-    public void test_store_parameters_defaults_to_false_with_latest_index_version_when_synthetic_source_is_enabled() throws IOException {
+    public void test_store_parameter_defaults_to_false_with_latest_index_version_when_synthetic_source_is_enabled() throws IOException {
         var indexSettings = getIndexSettingsBuilder().put(IndexSettings.INDEX_MAPPER_SOURCE_MODE_SETTING.getKey(), "synthetic").build();
 
         var mapping = mapping(b -> {