Function executeRCommand

src/util.ts:364–407

(rCommand: string, cwd?: string | URL, fallback?: string | ((e: Error) => string))

// Single quotes are ok.
//
export async function executeRCommand(rCommand: string, cwd?: string | URL, fallback?: string | ((e: Error) => string)): Promise<string | undefined> {
    const rPath = await getRpath();
    if (!rPath) {
        return undefined;
    }

    const options: cp.CommonOptions = {
        cwd: cwd,
    };

    const lim = '---vsc---';
    const args = [
        '--silent',
        '--no-echo',
        '--no-save',
        '--no-restore',
        '-e', `cat('${lim}')`,
        '-e', rCommand,
        '-e', `cat('${lim}')`
    ];

    let ret: string | undefined = undefined;

    try {
        const result = await spawnAsync(rPath, args, options);
        if (result.status !== 0) {
            throw result.error || new Error(result.stderr);
        }
        const re = new RegExp(`${lim}(.*)${lim}`, 'ms');
        const match = re.exec(result.stdout);
        if (!match || match.length !== 2) {
            throw new Error('Could not parse R output.');
        }
        ret = match[1];
    } catch (e) {
        if (fallback) {
            ret = (typeof fallback === 'function' ? fallback(catchAsError(e)) : fallback);
        } else {
            console.warn(e);
        }
    }

    return ret;
}


// This class is a wrapper around Map<string, any> that implements vscode.Memento