Code review fixes.

Author: GalLalouche

modules/mapper-extras/src/test/java/org/elasticsearch/index/mapper/extras/FieldCapsRankFeatureTests.java

@@ -59,10 +59,7 @@ public void testRankFeatureInIndex() {
         Map<String, FieldCapabilities> fooRankField = response.getField("fooRank");
         assertEquals(1, fooRankField.size());
         assertThat(fooRankField, Matchers.hasKey("rank_feature"));
-        assertEquals(
-            new FieldCapabilitiesBuilder("fooRank", "rank_feature").isAggregatable(false).build(),
-            fooRankField.get("rank_feature")
-        );
+        assertEquals(fieldCapabilities("fooRank"), fooRankField.get("rank_feature"));
     }
 
     public void testRankFeatureInIndexAfterRestart() throws Exception {

test/framework/src/main/java/org/elasticsearch/action/fieldcaps/FieldCapabilitiesBuilder.java

@@ -12,6 +12,9 @@
 import org.elasticsearch.core.Nullable;
 import org.elasticsearch.index.mapper.TimeSeriesParams;
 
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashMap;
 import java.util.Map;
 import java.util.Set;
 
@@ -40,7 +43,7 @@ public FieldCapabilitiesBuilder(String name, String type) {
         this.isSearchable = true;
         this.isAggregatable = true;
 
-        this.meta = Map.of();
+        this.meta = Collections.emptyMap();
     }
 
     public FieldCapabilitiesBuilder isMetadataField(boolean isMetadataField) {
@@ -69,7 +72,7 @@ public FieldCapabilitiesBuilder metricType(TimeSeriesParams.MetricType metricTyp
     }
 
     public FieldCapabilitiesBuilder indices(String... indices) {
-        this.indices = indices;
+        this.indices = Arrays.copyOf(indices, indices.length);
         return this;
     }
 
@@ -94,7 +97,7 @@ public FieldCapabilitiesBuilder metricConflictsIndices(String... metricConflicts
     }
 
     public FieldCapabilitiesBuilder meta(Map<String, Set<String>> meta) {
-        this.meta = meta;
+        this.meta = new HashMap<>(meta);
         return this;
     }
 

x-pack/plugin/ml/src/test/java/org/elasticsearch/xpack/ml/dataframe/extractor/ExtractedFieldsDetectorTests.java

@@ -1716,10 +1716,7 @@ private MockFieldCapsResponseBuilder addField(String field, boolean isMetadataFi
             for (String type : types) {
                 caps.put(
                     type,
-                    new FieldCapabilitiesBuilder(field, type).isMetadataField(isMetadataField)
-                        .isSearchable(true)
-                        .isAggregatable(isAggregatable)
-                        .build()
+                    new FieldCapabilitiesBuilder(field, type).isMetadataField(isMetadataField).isAggregatable(isAggregatable).build()
                 );
             }
             fieldCaps.put(field, caps);

x-pack/plugin/sql/src/test/java/org/elasticsearch/xpack/sql/analysis/index/IndexResolverTests.java

@@ -284,7 +284,7 @@ public void testMergeIncompatibleCapabilitiesOfObjectFields() throws Exception {
 
         Map<String, FieldCapabilities> multi = new HashMap<>();
         multi.put("long", new FieldCapabilitiesBuilder(fieldName, "long").indices("one-index").build());
-        multi.put("text", new FieldCapabilitiesBuilder(fieldName, "text").indices("another-index").build());
+        multi.put("text", new FieldCapabilitiesBuilder(fieldName, "text").indices("another-index").isAggregatable(false).build());
         fieldCaps.put(fieldName, multi);
 
         String wildcard = "*";