fix(list-key-manager): align matching logic with native listbox

[crisbeto]

Currently the typeahead option of the ListKeyManager looks for matches from start to end which can lead to some weird behavior where the user might be half-way down the list, but be sent up to the first item (e.g. in a list of b, a, ba it would always find b). These changes align the behavior closer to the native listbox by looking for the next match after the active item. If no match is found, the selection wraps around and starts looking from the beginning.

[jelbourn]

Use mod instead of manually wrapping?

const items = this._items.toArray();

// Start at 1 because we want to start searching at the item immediately
// following the current active item.
for (let i = 1; i < items.length; i++) {
  const index = (this._activeItemIndex + i) % items.length;
  if (items[index].getLabel!().toUpperCase().trim().indexOf(inputString) === 0) {
    this.setActiveItem(index);
    break;
  }
}

[crisbeto]

Hmm interesting. It doesn't seem to work on smaller lists though, E.g. on one of the unit tests we have a list of one, two, three but it never reaches three.

[jelbourn]

This always does what I'd expect:

var items = ['one', 'two', 'three'];
var activeIndex = 1;
for (let i = 1; i < items.length; i++) {
  const index = (activeIndex + i) % items.length;
  console.log(index, ' ', items[index]);
}

You mean for it to always skip the active item, right?

[crisbeto]

It's supposed to skip it but then wrap around if it doesn't find anything else. I got it working like this:

for (let i = 1; i < items.length + 1; i++) {
  const index = (this._activeItemIndex + i) % items.length;
  if (items[index].getLabel!().toUpperCase().trim().indexOf(inputString) === 0) {
    this.setActiveItem(index);
    break;
  }
}

Also I think you had a typo. The this.setActiveItem(i) was supposed to be this.setActiveItem(index).

[jelbourn]

Yeah, I did have that typo.

[jelbourn]

LGTM

[andrewseguin]

Please rebase

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