How to use the yaml-ast-parser.Kind.SCALAR function in yaml-ast-parser

function recursiveObjectExtraction(node: YAMLNode | undefined, object: PlainObject, validationContext: ValidationContext, source: ProjectSource): any {
    // ATTENTION: Typings of the yaml ast parser are wrong
    if (!node) {
        return object;
    }
    switch (node.kind) {
        case Kind.MAP:
            const mapNode = node as YamlMap;
            mapNode.mappings.forEach(val => {
                object[val.key.value] = recursiveObjectExtraction(val.value, {}, validationContext, source);
            });
            return object;
        case Kind.MAPPING:
            throw new Error('Should never be reached since a mapping can not exist without a map.');
        case Kind.SCALAR:
            const scalarNode = node as YAMLScalar;
            // check whether string or number scalar
            if (scalarNode.doubleQuoted || scalarNode.singleQuoted || isNaN(Number(scalarNode.value))) {
                return scalarNode.value;
            } else {
                return Number(scalarNode.value);
            }
        case Kind.SEQ:
            const seqNode = node as YAMLSequence;
            return seqNode.items.map(val => recursiveObjectExtraction(val, {}, validationContext, source));
        case Kind.INCLUDE_REF:
            validationContext.addMessage(ValidationMessage.error(`Include references are not supported`, new MessageLocation(source, node.startPosition, node.endPosition)));
            return undefined;
        case Kind.ANCHOR_REF:
            validationContext.addMessage(ValidationMessage.error(`Anchor references are not supported`, new MessageLocation(source, node.startPosition, node.endPosition)));
            return undefined;

}
    
        }
        
        //Autocompletion on root nodes
        //Case 1 covered
        if(parentNodeList.length === 0){
            return Object.keys(this.kuberSchema["rootNodes"]).map(x => ({
                label: x
            }));
        }

        //Autocompletion on scalar nodes
        //Case 2 Covered
        if(parentList.length === 1 && (node && (node.value && node.value.kind === Kind.SCALAR) || node.kind === Kind.SCALAR)){
            return this.autoCompleteScalarResults(nodesToSearch);
        }

        let possibleChildren = [];
        while(nodesToSearch.length > 0){
            let currNodePath = nodesToSearch.shift(); 
            let depth = currNodePath.length - 1;
            let currNode = currNodePath[depth];

            //Autocompletion on deep child nodes
            if(currNodePath.length === parentList.length){
                possibleChildren.push(currNode);
            }

            if(currNode["items"] && currNode["items"]["properties"]){
                if(currNode["items"]["properties"][parentList[currNodePath.length]]){

//For Kedge and normal schemas
                if(api_obj === parentList[0]){
                    nodesToSearch.push([this.schema.properties[api_obj]]);
                }
                rootNodeList.push(api_obj);
                 
            }
        }

        if(parentNodeList.length === 0){
            let rootNodes = Array.from(new Set(rootNodeList));
            return callback([],[], rootNodes);
        }

        //Return early when we found a scalar node at the root level i.e. key: value <- here
        if(returnEarlyForScalar && parentList.length === 1 && (node && (node.value && node.value.kind === Kind.SCALAR) || node.kind === Kind.SCALAR)){
            return callback([], nodesToSearch, []);
        }

        let possibleChildren = [];
        while(nodesToSearch.length > 0){
            let currNodePath = nodesToSearch.shift(); 
            let depth = currNodePath.length - 1;
            let currNode = currNodePath[depth];

            if(currNodePath.length === parentList.length){
                possibleChildren.push(currNode);
            }

            //This is when its an array
            if(currNode["items"] && currNode["items"]["properties"]){
                if(currNode["items"]["properties"][parentList[currNodePath.length]]){