Fixes#10696
# Description
As reported, you could mess up the ring of remembered directories in
`std dirs` (a.k.a the `shells` commands) with a sequence like this:
```
~/test> mkdir b c
~/test> pushd b
~/test/b> cd ../c
~/test/c> goto 0
~/test> goto 1
## expect to end up in ~/test/c
## observe you're in ~/test/b
~/test/b>
```
Problem was `dirs goto` was not updating the remembered directories
before leaving the current slot for some other. This matters if the user
did a manual `cd` (which cannot update the remembered directories ring)
# User-Facing Changes
None! it just works ™️
# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`
# After Submitting
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documentation](https://github.com/nushell/nushell.github.io) after the
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# Description
For years, Nushell has used `let-env` to set a single environment
variable. As our work on scoping continued, we refined what it meant for
a variable to be in scope using `let` but never updated how `let-env`
would work. Instead, `let-env` confusingly created mutations to the
command's copy of `$env`.
So, to help fix the mental model and point people to the right way of
thinking about what changing the environment means, this PR removes
`let-env` to encourage people to think of it as updating the command's
environment variable via mutation.
Before:
```
let-env FOO = "BAR"
```
Now:
```
$env.FOO = "BAR"
```
It's also a good reminder that the environment owned by the command is
in the `$env` variable rather than global like it is in other shells.
# User-Facing Changes
BREAKING CHANGE BREAKING CHANGE
This completely removes `let-env FOO = "BAR"` so that we can focus on
`$env.FOO = "BAR"`.
# Tests + Formatting
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# After / Before Submitting
integration scripts to update:
- ✔️
[starship](https://github.com/starship/starship/blob/master/src/init/starship.nu)
- ✔️
[virtualenv](https://github.com/pypa/virtualenv/blob/main/src/virtualenv/activation/nushell/activate.nu)
- ✔️
[atuin](https://github.com/ellie/atuin/blob/main/atuin/src/shell/atuin.nu)
(PR: https://github.com/ellie/atuin/pull/1080)
- ❌
[zoxide](https://github.com/ajeetdsouza/zoxide/blob/main/templates/nushell.txt)
(PR: https://github.com/ajeetdsouza/zoxide/pull/587)
- ✔️
[oh-my-posh](https://github.com/JanDeDobbeleer/oh-my-posh/blob/main/src/shell/scripts/omp.nu)
(pr: https://github.com/JanDeDobbeleer/oh-my-posh/pull/4011)
# Description
When the directory stack contains only two directories, then std dirs
drop
used to misbehave and (essentially) drop the other directory, instead of
dropping the current directory.
This is fixed by always cd'ing for std dirs drop.
Before:
/tmp〉enter ..
/〉dexit
/〉
After:
/tmp〉enter ..
/〉dexit
/tmp〉
Additionally, I propose to explain the relevant environment variables a
bit
more thoroughly.
# User-Facing Changes
- Fix bug in dexit (std dirs drop) when two directories are remaining
# Tests + Formatting
Added a regression test. Made the existing test easier to understand.