Add ES|QL copy_sign function

Author: vitaliidm

x-pack/plugin/esql/src/main/generated/org/elasticsearch/xpack/esql/expression/function/scalar/math/CopySignEvaluator.java

@@ -77,6 +77,7 @@
 import org.elasticsearch.xpack.esql.expression.function.scalar.math.Atan2;
 import org.elasticsearch.xpack.esql.expression.function.scalar.math.Cbrt;
 import org.elasticsearch.xpack.esql.expression.function.scalar.math.Ceil;
+import org.elasticsearch.xpack.esql.expression.function.scalar.math.CopySign;
 import org.elasticsearch.xpack.esql.expression.function.scalar.math.Cos;
 import org.elasticsearch.xpack.esql.expression.function.scalar.math.Cosh;
 import org.elasticsearch.xpack.esql.expression.function.scalar.math.E;
@@ -298,6 +299,7 @@ private static FunctionDefinition[][] functions() {
                 def(Atan2.class, Atan2::new, "atan2"),
                 def(Cbrt.class, Cbrt::new, "cbrt"),
                 def(Ceil.class, Ceil::new, "ceil"),
+                def(CopySign.class, CopySign::new, "copy_sign"),
                 def(Cos.class, Cos::new, "cos"),
                 def(Cosh.class, Cosh::new, "cosh"),
                 def(E.class, E::new, "e"),

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

@@ -0,0 +1,133 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+package org.elasticsearch.xpack.esql.expression.function.scalar.math;
+
+import org.elasticsearch.common.io.stream.NamedWriteableRegistry;
+import org.elasticsearch.common.io.stream.StreamInput;
+import org.elasticsearch.common.io.stream.StreamOutput;
+import org.elasticsearch.compute.ann.Evaluator;
+import org.elasticsearch.compute.operator.EvalOperator.ExpressionEvaluator;
+import org.elasticsearch.xpack.esql.core.expression.Expression;
+import org.elasticsearch.xpack.esql.core.tree.NodeInfo;
+import org.elasticsearch.xpack.esql.core.tree.Source;
+import org.elasticsearch.xpack.esql.core.type.DataType;
+import org.elasticsearch.xpack.esql.core.util.NumericUtils;
+import org.elasticsearch.xpack.esql.expression.function.Example;
+import org.elasticsearch.xpack.esql.expression.function.FunctionInfo;
+import org.elasticsearch.xpack.esql.expression.function.Param;
+import org.elasticsearch.xpack.esql.expression.function.scalar.EsqlScalarFunction;
+import org.elasticsearch.xpack.esql.io.stream.PlanStreamInput;
+
+import java.io.IOException;
+import java.util.Arrays;
+import java.util.List;
+
+import static org.elasticsearch.xpack.esql.core.expression.TypeResolutions.ParamOrdinal.FIRST;
+import static org.elasticsearch.xpack.esql.core.expression.TypeResolutions.ParamOrdinal.SECOND;
+import static org.elasticsearch.xpack.esql.core.expression.TypeResolutions.isNumeric;
+
+public class CopySign extends EsqlScalarFunction {
+    public static final NamedWriteableRegistry.Entry ENTRY = new NamedWriteableRegistry.Entry(Expression.class, "CopySign", CopySign::new);
+
+    private final Expression magnitude;
+    private final Expression sign;
+
+    @FunctionInfo(
+        returnType = { "double" },
+        description = "Returns the first argument with the sign of the second argument.",
+        examples = @Example(file = "math", tag = "CopySign")
+    )
+    public CopySign(
+        Source source,
+        @Param(
+            name = "magnitude",
+            type = { "double", "integer", "long", "unsigned_long" },
+            description = "Numeric expression. If `null`, the function returns `null`."
+        ) Expression magnitude,
+        @Param(
+            name = "sign",
+            type = { "double", "integer", "long", "unsigned_long" },
+            description = "Numeric expression. If `null`, the function returns `null`."
+        ) Expression sign
+    ) {
+        super(source, Arrays.asList(magnitude, sign));
+        this.magnitude = magnitude;
+        this.sign = sign;
+    }
+
+    private CopySign(StreamInput in) throws IOException {
+        this(Source.readFrom((PlanStreamInput) in), in.readNamedWriteable(Expression.class), in.readNamedWriteable(Expression.class));
+    }
+
+    @Override
+    public void writeTo(StreamOutput out) throws IOException {
+        source().writeTo(out);
+        out.writeNamedWriteable(magnitude);
+        out.writeNamedWriteable(sign);
+    }
+
+    @Override
+    public String getWriteableName() {
+        return ENTRY.name;
+    }
+
+    @Override
+    protected TypeResolution resolveType() {
+        if (childrenResolved() == false) {
+            return new TypeResolution("Unresolved children");
+        }
+
+        TypeResolution resolution = isNumeric(magnitude, sourceText(), FIRST);
+        if (resolution.unresolved()) {
+            return resolution;
+        }
+
+        return isNumeric(sign, sourceText(), SECOND);
+    }
+
+    @Override
+    public boolean foldable() {
+        return magnitude.foldable() && sign.foldable();
+    }
+
+    @Evaluator(warnExceptions = { ArithmeticException.class })
+    static double process(double magnitude, double sign) {
+        return NumericUtils.asFiniteNumber(Math.copySign(magnitude, sign));
+    }
+
+    @Override
+    public Expression replaceChildren(List<Expression> newChildren) {
+        return new CopySign(source(), newChildren.get(0), newChildren.get(1));
+    }
+
+    @Override
+    protected NodeInfo<? extends Expression> info() {
+        return NodeInfo.create(this, CopySign::new, magnitude(), sign());
+    }
+
+    public Expression magnitude() {
+        return magnitude;
+    }
+
+    public Expression sign() {
+        return sign;
+    }
+
+    @Override
+    public DataType dataType() {
+        return DataType.DOUBLE;
+    }
+
+
+    @Override
+    public ExpressionEvaluator.Factory toEvaluator(ToEvaluator toEvaluator) {
+        var magnitudeEval = Cast.cast(source(), magnitude.dataType(), DataType.DOUBLE, toEvaluator.apply(magnitude));
+        var signEval = Cast.cast(source(), sign.dataType(), DataType.DOUBLE, toEvaluator.apply(sign));
+        return new CopySignEvaluator.Factory(source(), magnitudeEval, signEval);
+    }
+}