Function extendSelection

src/selection.ts:209–287

(line: number, getLine: (line: number) => string, lineCount: number)

 * @param lineCount The number of lines in the document.
 */
export function extendSelection(line: number, getLine: (line: number) => string, lineCount: number): {
    startLine: number;
    endLine: number;
} {
    const lc = new LineCache(getLine, lineCount);
    const getLineFromCache = (x: number) => lc.getLineFromCache(x);
    const getEndsInOperatorFromCache = (x: number) => lc.getEndsInOperatorFromCache(x);
    let lookingForward = true;
    /* poss[1] is the farthest point reached looking forward from line,
     and poss[0] is the farthest point reached looking backward from line. */
    const poss = { 0: new PositionNeg(line, 0), 1: new PositionNeg(line, -1) };
    const flagsFinish = { 0: false, 1: false }; // 1 represents looking forward, 0 represents looking back.
    let flagAbort = false;
    const unmatched = { 0: [] as string[], 1: [] as string[] };
    let curChar = '';
    let quoteChar = '';
    while (!flagAbort && !(flagsFinish[0] && flagsFinish[1])) {
        const { nextChar, nextPos, isEndOfCodeLine, isEndOfFile } = getNextChar(
            poss[lookingForward ? 1 : 0],
            lookingForward,
            getLineFromCache,
            getEndsInOperatorFromCache,
            lineCount
        );
        poss[lookingForward ? 1 : 0] = nextPos;
        if (quoteChar === '') {
            if (isQuote(nextChar)) {
                quoteChar = nextChar;
            } else {
                if (isBracket(nextChar, lookingForward)) {
                    unmatched[lookingForward ? 1 : 0].push(nextChar);
                } else if (isBracket(nextChar, !lookingForward)) {
                    if (unmatched[lookingForward ? 1 : 0].length === 0) {
                        lookingForward = !lookingForward;
                        unmatched[lookingForward ? 1 : 0].push(nextChar);
                        flagsFinish[lookingForward ? 1 : 0] = false;
                    } else if (!doBracketsMatch(nextChar, unmatched[lookingForward ? 1 : 0].pop() ?? '')) {
                        flagAbort = true;
                    }
                }
            }
        } else {
            if (nextChar === quoteChar) {
                if (lookingForward) {
                    if (curChar !== '\\') {
                        quoteChar = '';
                    }
                } else {
                    const next = getNextChar(poss[lookingForward ? 1 : 0],
                        lookingForward,
                        getLineFromCache,
                        getEndsInOperatorFromCache,
                        lineCount);
                    if (next.nextChar !== '\\') {
                        quoteChar = '';
                    }
                }
            }