Filtering on keys which hold the value of numerical zero gives inaccurate results

[pushpinder107]

• match-sorter version: 2.2.1
• node version: 8.9.4
• npm (or yarn) version: 5.6.0

Relevant code or config

return value ? [].concat(value) : null

What you did:
Use data which contains the number 0 as a property value as below:

const objList = [
  {name: 'Janice', color: 'Green', rank:0},
  {name: 'Fred', color: 'Orange', rank:100},
  {name: 'George', color: 'Blue', rank:20},
  {name: 'Jen', color: 'Red', rank:0},
]

What happened:

The rows which have the numerical value zero are rejected falsely by the null check done while getting all items to compare.

Problem description:

matchSorter(objList, '0', {keys: ['name', 'rank']})

this returns:

[ {name: 'Fred', color: 'Orange', rank: 100 },
  { name: 'George', color: 'Blue', rank: 20 } ]

but should return:

[ {name: 'Janice', color: 'Green', rank:0},
{name: 'Jen', color: 'Red', rank:0}
{name: 'Fred', color: 'Orange', rank: 100 },
{name: 'George', color: 'Blue', rank: 20 } ]

Suggested solution:

Adding a check for the number zero in the return value of the function getItemValues.

return value || value === 0 ? [].concat(value) : null