Add padding when pressing space between a pair of curly braces

[noinkling]

When I type { to create a pair of curly braces:

{}

...and then when I press space, I would like 2 spaces to be inserted with the cursor in the middle:

{ | }
  ^ cursor

Currently it just inserts a single space, so getting the same result requires pressing space twice then the back arrow once. Or otherwise setting:

"javascript.format.insertSpaceAfterOpeningAndBeforeClosingNonemptyBrackets": true
// or "typescript.format.insertSpaceAfterOpeningAndBeforeClosingNonemptyBrackets": true

...then formatting the line once there's already stuff inside it.

I believe pressing space between a pair of brackets with nothing between them ({}) is more-or-less an unambiguous signal (in pretty much any language) that the user intends to have a padding space at both ends. It's also very similar to the already-covered case where someone instead presses enter to produce:

{
  | <- cursor
}

In Sublime Text I was able to add the functionality myself using a keybinding that looked (in their format) like:

{ "keys": ["space"], "command": "insert_snippet", "args": {"contents": " $0 "}, "context":
  [
    { "key": "selection_empty", "operator": "equal", "operand": true, "match_all": true },
    { "key": "preceding_text", "operator": "regex_contains", "operand": "\\{$", "match_all": true },
    { "key": "following_text", "operator": "regex_contains", "operand": "^\\}", "match_all": true }
  ]
}

...but in VS Code there doesn't seem to be enough functionality available to add a keybinding like this - I can insert a snippet but can't see anything that would allow me to limit the context to the inside of a pair of brackets.

If someone points me to the place in the codebase where the similar behavior for pressing "enter" is defined, I might be able to open a PR myself.

[AiryShift]

I've looked around the codebase but have been unable to find the relevant locations. In the meantime, I made this extension which should do what you've described.

[noinkling]

@AiryShift Big thanks for throwing that together, I like the name 😄 I did find a bug where it causes the undo command to get stuck in a loop, hopefully that isn't too hard to fix.

As far as the request goes, I should probably add that it could be applied to square brackets and parens as well (obviously), it's just that curly braces seem to be the most common use case.

Edit: update in case anyone else is reading this; the undo bug in the above extension was fixed, and support added for the other types of braces. Thanks again @AiryShift 👍