Essentially, if accepted completion string matches a given regexp
pattern, text can be inserted both before and after point.
This is useful in certain situations where Copilot suggests the opening
line to a if statement, for loop, etc., which leads to unbalanced curly
brackets. This can help reduce the annoyance of unbalanced brackets.
Instead of stripping away curly brackets at the end of the completion
texts, simply insert a closing curly bracket after point when accepting
a completion that ends with a curly bracket.
In languages that uses "{" for blocks, accepting a Copilot completion
that ends with "{", causing a structural imbalance, which
structural-based packages like smartparens does not like and causes
headaches.
With the custom accept function, trailing "{" chars along with any
whitespace before it, are ignored from Copilot completion. An exception
is made for if the removal of trailing "{" and whitespace yields an
empty completion, in which case the completion is accepted as is.
Previously we only hide company-mode's in-line preview when there was
only a single result. This meant that it didn't show the one result
anywhere.
This allows company-mode to still show it's regular popup even when
there's only one result.
I opted for accepting copilot completions using C-<tab> /
<backtab> (shift+tab) instead of regular tab, as it was often getting in
the way of yasnippet and lsp completion suggestions. This allows a more
explicit acceptance of Copilot suggestions.
