glennj
July 23, 2025, 7:37pm
1
Task 3 says (emphasis mine):
[…] write a function fixBirdCountLog that takes an array of birds counted per day as an argument. It should correct the counting mistake and return the modified array
But the tests expect the input “array” to be modified in-place. javascript/exercises/concept/bird-watcher/bird-watcher.spec.js at 6b1bb1269d211e9f75e4f34b89e92b00382ebe34 · exercism/javascript · GitHub
I coded this:
export function fixBirdCountLog(birdsPerDay) {
const fixed = new Array(birdsPerDay.length);
for (let i = 0; i < birdsPerDay.length; i++) {
fixed[i] = birdsPerDay[i] + (i % 2 == 0 ? 1 : 0);
}
return fixed;
}
But the tests need this:
export function fixBirdCountLog(birdsPerDay) {
for (let i = 0; i < birdsPerDay.length; i+=2) {
birdsPerDay[i]++;
}
return;
}
2 Likes
The stub has a comment indicating nothing should be returned, which doesn’t contradict the test suite. It seems reasonable to me to perhaps update the docs. Would saying something like modify the array in-place be more clear than return the modified array?
*/
export function birdsInWeek(birdsPerDay, week) {
throw new Error('Remove this line and implement the function');
}
/**
* Fixes the counting mistake by increasing the bird count
* by one for every second day.
*
* @param {number[]} birdsPerDay
* @returns {void} should not return anything
*/
export function fixBirdCountLog(birdsPerDay) {
throw new Error('Remove this line and implement the function');
}
IsaacG
July 23, 2025, 7:57pm
3
Maybe just modify the array? Coupled with no return value, that ought to be clear and simple.
2 Likes
I like modify the array in-place but the simpler version (modify the array) is probably better and less confusing.
PRs welcome.
1 Like