The current auto indent implementation is such that when we click on Enter from within [], {}, (), an indentation is added on the next line only if the opening bracket was adjacent to the closing bracket as follows (here | indicates the cursor position):

function f(|)

In some cases, we want to have the next line indented, even if the brackets are not adjancent. Consider the following case:

const array = [1, 2, 3];
array.map(_|)

In this case when Enter is pressed at the cursor position, we would expect the following indentation to happen:

const array = [1, 2, 3];
array.map(_
    |
)

Instead currently we see this:

const array = [1, 2, 3];
array.map(_
|)

This PR aims to address this by introducing extended onEnter rules where we indent whenever the cursor is located after an opening bracket and is followed by whitespace characters and the corresponding closing bracket.