@github/text-expander-element/dist/query.js

Activates a suggestion menu to expand text snippets as you type.

const boundary = /\s|\(|\[/;
export default function query(text, key, cursor, { multiWord, lookBackIndex, lastMatchPosition } = {
    multiWord: false,
    lookBackIndex: 0,
    lastMatchPosition: null
}) {
    let keyIndex = text.lastIndexOf(key, cursor - 1);
    if (keyIndex === -1)
        return;
    if (keyIndex < lookBackIndex)
        return;
    if (multiWord) {
        if (lastMatchPosition != null) {
            if (lastMatchPosition === keyIndex)
                return;
            keyIndex = lastMatchPosition - key.length;
        }
        const charAfterKey = text[keyIndex + 1];
        if (charAfterKey === ' ' && cursor >= keyIndex + key.length + 1)
            return;
        const newLineIndex = text.lastIndexOf('\n', cursor - 1);
        if (newLineIndex > keyIndex)
            return;
        const dotIndex = text.lastIndexOf('.', cursor - 1);
        if (dotIndex > keyIndex)
            return;
    }
    else {
        const spaceIndex = text.lastIndexOf(' ', cursor - 1);
        if (spaceIndex > keyIndex)
            return;
    }
    const pre = text[keyIndex - 1];
    if (pre && !boundary.test(pre))
        return;
    const queryString = text.substring(keyIndex + key.length, cursor);
    return {
        text: queryString,
        position: keyIndex + key.length
    };
}