function wrapMultiResult(arr) {
    // When using WATCH/EXEC transactions, the EXEC will return
    // a null instead of an array
    if (!arr) {
        return null;
    }
    const result = [];
    const length = arr.length;
    for (let i = 0; i < length; ++i) {
        const item = arr[i];
        if (item instanceof Error) {
            result.push([item]);
        }
        else {
            result.push([null, item]);
        }
    }
    return result;
}
Convert a list of results to node-style

@param {Array} arr - The input value
@return {Array} The output value
@example
```js
var input = ['a', 'b', new Error('c'), 'd']
var output = exports.wrapMultiResult(input)
expect(output).to.eql([[null, 'a'], [null, 'b'], [new Error('c')], [null, 'd'])
```
@private