# Description
Add an extension trait `IgnoreCaseExt` to nu_utils which adds some case
insensitivity helpers, and use them throughout nu to improve the
handling of case insensitivity. Proper case folding is done via unicase,
which is already a dependency via mime_guess from nu-command.
In actuality a lot of code still does `to_lowercase`, because unicase
only provides immediate comparison and doesn't expose a `to_folded_case`
yet. And since we do a lot of `contains`/`starts_with`/`ends_with`, it's
not sufficient to just have `eq_ignore_case`. But if we get access in
the future, this makes us ready to use it with a change in one place.
Plus, it's clearer what the purpose is at the call site to call
`to_folded_case` instead of `to_lowercase` if it's exclusively for the
purpose of case insensitive comparison, even if it just does
`to_lowercase` still.
# User-Facing Changes
- Some commands that were supposed to be case insensitive remained only
insensitive to ASCII case (a-z), and now are case insensitive w.r.t.
non-ASCII characters as well.
# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`
---------
Co-authored-by: Stefan Holderbach <sholderbach@users.noreply.github.com>
This pr fix clippy warnings in latest clippy version(1.72.0):
Unfortunally it's not easy to handle for [try
fold](https://rust-lang.github.io/rust-clippy/master/index.html#/manual_try_fold)
warning in `start command`
Refer to known issue:
> This lint doesn’t take into account whether a function does something
on the failure case, i.e., whether short-circuiting will affect
behavior. Refactoring to try_fold is not desirable in those cases.
That's the case for our code, which does something on the failure case.
So this pr is making a little refactor on `try_commands`.
