search.ts

const ordinalize = (cond1: boolean, cond2: boolean): -1 | 0 | 1 => {
  if (cond1 && !cond2) return -1
  if (!cond1 && cond2) return 1
  return 0
}

const sortResults = (query: string, unsortedList: string[]): string[] => {
  const exact = new RegExp(`^${query}$`)
  const startsWith = new RegExp(`^${query}`)
  const aWordMatchesIn = item => item.split(' ').reduce(
    (acc, word) => acc || !!exact.test(word),
    false
  )
  const sortedList = [ ...unsortedList ]
  return sortedList.sort((a, b) =>
    ordinalize(exact.test(a), exact.test(b)) ||
    ordinalize(aWordMatchesIn(a), aWordMatchesIn(b)) ||
    ordinalize(startsWith.test(a), startsWith.test(b))
  )

}

[{
  query: 'omni',
  input: ['omni plan', 'pomnit', 'omnigraffle', 'omni'],
}].forEach(({ query, input }) => {
  console.log({ input, output: sortResults(query, input) })
})