Here are the instructions.
Your function must always return the entire record collection object.
If prop isn't tracks and value isn't an empty string, update or set that album's prop to value.
If prop is tracks but the album doesn't have a tracks property, create an empty array and add value to it.
If prop is tracks and value isn't an empty string, add value to the end of the album's existing tracks array.
If value is an empty string, delete the given prop property from the album. Note: A copy of the recordCollection object is used for the tests.
My solution was:
function updateRecords(records, id, prop, value) {
return records;
if (prop !== "tracks" && value !== "") {
records[id][prop] = value;
} else if (prop == "tracks" && records[id].hasOwnProperty("tracks") == false) {
records[id][prop] = [value];
} else if (prop == "tracks" && value !== "") {
records[id][prop].push(value);
} else if (value == "") {
delete records[id][prop];
}
return records;
}
updateRecords(recordCollection, 5439, 'artist', 'ABBA');
Why didn't this work?
One possible solution to this task
const recordCollection={2548:{albumTitle:"Slippery When Wet",artist:"Bon Jovi",tracks:["Let It Rock","You Give Love a Bad Name"]},2468:{albumTitle:"1999",artist:"Prince",tracks:["1999","Little Red Corvette"]},1245:{artist:"Robert Palmer",tracks:[]},5439:{albumTitle:"ABBA Gold"}};
function updateRecords(records, id, prop, value) {
const record = records[id];
if (!value) {
delete record[prop];
return records;
}
if (prop === 'tracks') {
record[prop] ??= [];
record[prop].push(value);
return records;
}
record[prop] = value;
return records;
};
console.log(updateRecords(recordCollection, 5439, 'artist', 'ABBA')[5439]);
console.log(updateRecords(recordCollection, 5439, "tracks", "Take a Chance on Me")[5439]);
console.log(updateRecords(recordCollection, 2548, "artist", "")[2548])
console.log(updateRecords(recordCollection, 1245, "tracks", "Addicted to Love")[1245])
console.log(updateRecords(recordCollection, 2548, "tracks", "")[2548])
console.log(updateRecords(recordCollection, 1245, "albumTitle", "Riptide")[1245]).as-console-wrapper {max-height: 100% !important; top: 0}the way to do that:
first create significant records for testing.
PS: using Logical nullish assignment (??=) greatly simplifies the code.
const
rec0 = { 5439 : { prop1: "aaa" } }
, rec1 = { 5439 : { prop1: "aaa", artist: 'xyz' } }
, rec2 = { 5439 : { prop1: "aaa", artist: 'xyz' } }
, rec3 = { 5439 : { prop1: "aaa" }}
, rec4 = { 5439 : { prop1: "aaa", tracks: ['aa','bb','cc'] }}
, rec5 = { 5439 : { prop1: "aaa", tracks: ['aa','bb','cc'] }}
;
console.log( JSON.stringify( updateRecords( rec0, 5439, 'artist', 'ABBA' )))
console.log( JSON.stringify( updateRecords( rec1, 5439, 'artist', 'ABBA' )))
console.log( JSON.stringify( updateRecords( rec2, 5439, 'artist', '' )))
console.log( JSON.stringify( updateRecords( rec3, 5439, 'tracks', 't1' )))
console.log( JSON.stringify( updateRecords( rec4, 5439, 'tracks', 't1' )))
console.log( JSON.stringify( updateRecords( rec5, 5439, 'tracks', '' )))
function updateRecords(records, id, prop, value)
{
if (prop == 'tracks')
{
records[id].tracks ??= [];
if (value.length) records[id].tracks.push(value);
else delete records[id].tracks;
}
else if (value.length)
records[id][prop] = value;
return records;
}
.as-console-wrapper {max-height: 100% !important;top: 0;}
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