こんにちは!アルダグラムのKANNAの開発お手伝いをさせて頂いているoubakiouです。 本記事は株式会社アルダグラム Advent Calendar 2023 6日目の記事です。 この記事を読めば以下のTypeScript(JavaScript)のテストコードがなぜこけるのかが分かったような気持ちになります。また最後に「細かい理屈はいいからいけてる感じに動くlengthやtruncateがほしい!」という方向けの付録もついています。 it('surrogate pair', () => { // 2 expect('😊'.length).toEqual(1) }) it('variation selectors', () => { // 4 expect('👍🏿'.length).toEqual(1) }) it('combining character', () => { //
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