Fix some of the failing UTs

Author: julian-elastic

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/FunctionUtils.java

@@ -85,9 +85,8 @@ public static void postOptimizationVerificationQuery(Failures failures, Expressi
             failures.add(fail(queryField, "Query must be a valid string in [{}], found [{}]", sourceText, queryField));
         }
         if (queryField instanceof Literal literal) {
-            String value = BytesRefs.toString(literal.value());
-            if (value == null) {
-                failures.add(fail(queryField, "Invalid query value in [{}], found [{}]", sourceText, value));
+            if (literal.value() == null) {
+                failures.add(fail(queryField, "Invalid query value in [{}], found [{}]", sourceText, literal.value()));
             }
         } else {
             // it is expected that the expression is a literal after folding
@@ -97,6 +96,15 @@ public static void postOptimizationVerificationQuery(Failures failures, Expressi
     }
 
     public static Object queryAsObject(Expression queryField, String sourceText) {
+        if (queryField instanceof Literal literal) {
+            return literal.value();
+        }
+        throw new EsqlIllegalArgumentException(
+            format(null, "Query value must be a constant string in [{}], found [{}]", sourceText, queryField)
+        );
+    }
+
+    public static String queryAsString(Expression queryField, String sourceText) {
         if (queryField instanceof Literal literal) {
             return BytesRefs.toString(literal.value());
         }

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/fulltext/FullTextFunction.java

@@ -133,15 +133,6 @@ public Expression query() {
         return query;
     }
 
-    /**
-     * Returns the resulting query as an object
-     *
-     * @return query expression as an object
-     */
-    public Object queryAsObject() {
-        return FunctionUtils.queryAsObject(query(), sourceText());
-    }
-
     @Override
     public Nullability nullable() {
         return Nullability.FALSE;

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/fulltext/Kql.java

@@ -20,6 +20,7 @@
 import org.elasticsearch.xpack.esql.expression.function.FunctionAppliesTo;
 import org.elasticsearch.xpack.esql.expression.function.FunctionAppliesToLifecycle;
 import org.elasticsearch.xpack.esql.expression.function.FunctionInfo;
+import org.elasticsearch.xpack.esql.expression.function.FunctionUtils;
 import org.elasticsearch.xpack.esql.expression.function.Param;
 import org.elasticsearch.xpack.esql.io.stream.PlanStreamInput;
 import org.elasticsearch.xpack.esql.planner.TranslatorHandler;
@@ -94,7 +95,7 @@ protected NodeInfo<? extends Expression> info() {
 
     @Override
     protected Query translate(TranslatorHandler handler) {
-        return new KqlQuery(source(), Objects.toString(queryAsObject()));
+        return new KqlQuery(source(), FunctionUtils.queryAsString(query(), sourceText()));
     }
 
     @Override

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/fulltext/Match.java

@@ -30,6 +30,7 @@
 import org.elasticsearch.xpack.esql.expression.function.FunctionAppliesTo;
 import org.elasticsearch.xpack.esql.expression.function.FunctionAppliesToLifecycle;
 import org.elasticsearch.xpack.esql.expression.function.FunctionInfo;
+import org.elasticsearch.xpack.esql.expression.function.FunctionUtils;
 import org.elasticsearch.xpack.esql.expression.function.MapParam;
 import org.elasticsearch.xpack.esql.expression.function.OptionalArgument;
 import org.elasticsearch.xpack.esql.expression.function.Param;
@@ -403,9 +404,8 @@ public BiConsumer<LogicalPlan, Failures> postAnalysisPlanVerification() {
         };
     }
 
-    @Override
     public Object queryAsObject() {
-        Object queryAsObject = super.queryAsObject();
+        Object queryAsObject = FunctionUtils.queryAsObject(query(), sourceText());
 
         // Convert BytesRef to string for string-based values
         if (queryAsObject instanceof BytesRef bytesRef) {

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/fulltext/MatchPhrase.java

@@ -27,6 +27,7 @@
 import org.elasticsearch.xpack.esql.expression.function.FunctionAppliesTo;
 import org.elasticsearch.xpack.esql.expression.function.FunctionAppliesToLifecycle;
 import org.elasticsearch.xpack.esql.expression.function.FunctionInfo;
+import org.elasticsearch.xpack.esql.expression.function.FunctionUtils;
 import org.elasticsearch.xpack.esql.expression.function.MapParam;
 import org.elasticsearch.xpack.esql.expression.function.OptionalArgument;
 import org.elasticsearch.xpack.esql.expression.function.Param;
@@ -260,9 +261,8 @@ public BiConsumer<LogicalPlan, Failures> postAnalysisPlanVerification() {
         };
     }
 
-    @Override
     public Object queryAsObject() {
-        Object queryAsObject = super.queryAsObject();
+        Object queryAsObject = FunctionUtils.queryAsObject(query(), sourceText());
 
         // Convert BytesRef to string for string-based values
         if (queryAsObject instanceof BytesRef bytesRef) {

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/fulltext/MultiMatch.java

@@ -27,6 +27,7 @@
 import org.elasticsearch.xpack.esql.expression.function.FunctionAppliesTo;
 import org.elasticsearch.xpack.esql.expression.function.FunctionAppliesToLifecycle;
 import org.elasticsearch.xpack.esql.expression.function.FunctionInfo;
+import org.elasticsearch.xpack.esql.expression.function.FunctionUtils;
 import org.elasticsearch.xpack.esql.expression.function.MapParam;
 import org.elasticsearch.xpack.esql.expression.function.OptionalArgument;
 import org.elasticsearch.xpack.esql.expression.function.Param;
@@ -343,7 +344,7 @@ protected Query translate(TranslatorHandler handler) {
             String fieldName = Match.getNameFromFieldAttribute(fieldAttribute);
             fieldsWithBoost.put(fieldName, 1.0f);
         }
-        return new MultiMatchQuery(source(), Objects.toString(queryAsObject()), fieldsWithBoost, getOptions());
+        return new MultiMatchQuery(source(), FunctionUtils.queryAsString(query(), sourceText()), fieldsWithBoost, getOptions());
     }
 
     @Override

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/fulltext/QueryString.java

@@ -24,6 +24,7 @@
 import org.elasticsearch.xpack.esql.expression.function.FunctionAppliesTo;
 import org.elasticsearch.xpack.esql.expression.function.FunctionAppliesToLifecycle;
 import org.elasticsearch.xpack.esql.expression.function.FunctionInfo;
+import org.elasticsearch.xpack.esql.expression.function.FunctionUtils;
 import org.elasticsearch.xpack.esql.expression.function.MapParam;
 import org.elasticsearch.xpack.esql.expression.function.OptionalArgument;
 import org.elasticsearch.xpack.esql.expression.function.Param;
@@ -355,7 +356,7 @@ protected NodeInfo<? extends Expression> info() {
 
     @Override
     protected Query translate(TranslatorHandler handler) {
-        return new QueryStringQuery(source(), Objects.toString(queryAsObject()), Map.of(), queryStringOptions());
+        return new QueryStringQuery(source(), FunctionUtils.queryAsString(query(), sourceText()), Map.of(), queryStringOptions());
     }
 
     @Override

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/fulltext/Term.java

@@ -25,6 +25,7 @@
 import org.elasticsearch.xpack.esql.expression.function.FunctionAppliesTo;
 import org.elasticsearch.xpack.esql.expression.function.FunctionAppliesToLifecycle;
 import org.elasticsearch.xpack.esql.expression.function.FunctionInfo;
+import org.elasticsearch.xpack.esql.expression.function.FunctionUtils;
 import org.elasticsearch.xpack.esql.expression.function.Param;
 import org.elasticsearch.xpack.esql.io.stream.PlanStreamInput;
 import org.elasticsearch.xpack.esql.plan.logical.LogicalPlan;
@@ -132,7 +133,7 @@ protected TypeResolutions.ParamOrdinal queryParamOrdinal() {
     @Override
     protected Query translate(TranslatorHandler handler) {
         // Uses a term query that contributes to scoring
-        return new TermQuery(source(), ((FieldAttribute) field()).name(), queryAsObject(), false, true);
+        return new TermQuery(source(), ((FieldAttribute) field()).name(), FunctionUtils.queryAsObject(query(), sourceText()), false, true);
     }
 
     @Override

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/vector/Knn.java

@@ -247,7 +247,6 @@ private Map<String, Object> knnQueryOptions() throws InvalidArgumentException {
         return matchOptions;
     }
 
-    @Override
     public List<Number> queryAsObject() {
         // we need to check that we got a list and every element in the list is a number
         Expression query = query();

x-pack/plugin/src/yamlRestTest/resources/rest-api-spec/test/esql/230_folding.yml

@@ -141,7 +141,7 @@ SAMPLE function with constant folding:
 
 ---
 
-Sample function with negative limit value after folding:
+SAMPLE function with negative limit value after folding:
   - do:
       catch: bad_request
       esql.query:
@@ -156,7 +156,7 @@ Sample function with negative limit value after folding:
 
 ---
 
-Match function with foldable query:
+MATCH function with foldable query:
   - do:
       esql.query:
         body:
@@ -179,7 +179,7 @@ Match function with foldable query:
 
 ---
 
-Match function with non-foldable query:
+MATCH function with non-foldable query:
   - do:
       catch: bad_request
       esql.query: