Refactor Div arithmetic function to accept data type explicitly (elastic#97832)

Author: luigidellaquila

x-pack/plugin/eql/src/main/java/org/elasticsearch/xpack/eql/expression/function/EqlFunctionRegistry.java

@@ -68,7 +68,7 @@ private FunctionDefinition[][] functions() {
             // Arithmetic
             new FunctionDefinition[] {
                 def(Add.class, Add::new, "add"),
-                def(Div.class, Div::new, "divide"),
+                def(Div.class, (BinaryBuilder<Div>) Div::new, "divide"),
                 def(Mod.class, Mod::new, "modulo"),
                 def(Mul.class, Mul::new, "multiply"),
                 def(ToNumber.class, ToNumber::new, "number"),

x-pack/plugin/ql/src/main/java/org/elasticsearch/xpack/ql/expression/predicate/operator/arithmetic/Div.java

@@ -17,23 +17,33 @@
  */
 public class Div extends ArithmeticOperation implements BinaryComparisonInversible {
 
+    private DataType dataType;
+
     public Div(Source source, Expression left, Expression right) {
+        this(source, left, right, null);
+    }
+
+    public Div(Source source, Expression left, Expression right, DataType dataType) {
         super(source, left, right, DefaultBinaryArithmeticOperation.DIV);
+        this.dataType = dataType;
     }
 
     @Override
     protected NodeInfo<Div> info() {
-        return NodeInfo.create(this, Div::new, left(), right());
+        return NodeInfo.create(this, Div::new, left(), right(), dataType);
     }
 
     @Override
     protected Div replaceChildren(Expression newLeft, Expression newRight) {
-        return new Div(source(), newLeft, newRight);
+        return new Div(source(), newLeft, newRight, dataType);
     }
 
     @Override
     public DataType dataType() {
-        return DataTypeConverter.commonType(left().dataType(), right().dataType());
+        if (dataType == null) {
+            dataType = DataTypeConverter.commonType(left().dataType(), right().dataType());
+        }
+        return dataType;
     }
 
     @Override