@Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;
        if (!super.equals(o)) return false;

        AssignFieldPathUpdate that = (AssignFieldPathUpdate) o;

        if (createMissingPath != that.createMissingPath) return false;
        if (removeIfZero != that.removeIfZero) return false;
        if (expression != null ? !expression.equals(that.expression) : that.expression != null) return false;
        if (fieldValue != null ? !fieldValue.equals(that.fieldValue) : that.fieldValue != null) return false;

        return true;
    }
@return Returns true if this assignment is an arithmetic operation.
document/src/main/java/com/yahoo/document/fieldpathupdate/AssignFieldPathUpdate.java