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Fix missing return in `map` / `filter`

easy
By FrontendAtlas Editorial · Updated Mar 31, 2026
A teammate refactored a simple array pipeline to use block-bodied arrow functions because it looked more readable. The shape still looks right, but now the result comes back empty or full of `undefined`. Fix the missing returns without changing the overall intent of the pipeline.
Examples
summarizeOpenTickets([{ title: ' Bug ', open: true }, { title: 'Chore', open: false }]) // ['BUG']

summarizeOpenTickets([{ title: ' Docs ', open: true }, { title: ' Test ', open: true }]) // ['DOCS','TEST']

Solution

Overview

export default function summarizeOpenTickets(tickets){

return tickets

.filter(ticket => {

return ticket.open;

})

.map(ticket => {

return ticket.title.trim().toUpperCase();

});

}

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