Ran [`shellcheck`](https://github.com/koalaman/shellcheck) on our 3
shell scripts and fixed the warnings. This caught that the scripts were
[broken because of their
shebang](https://www.shellcheck.net/wiki/SC3030):
```
〉./uninstall-all.sh
----------------------------------------------
Uninstall nu and all plugins from cargo/bin...
----------------------------------------------
./uninstall-all.sh: 8: Syntax error: "(" unexpected
```
```
〉shellcheck *.sh
In build-all-maclin.sh line 8:
NU_PLUGINS=(
^-- SC3030 (warning): In POSIX sh, arrays are undefined.
In build-all-maclin.sh line 18:
for plugin in "${NU_PLUGINS[@]}"
^--------------^ SC3054 (warning): In POSIX sh, array references are undefined.
In build-all-maclin.sh line 20:
echo '' && cd crates/$plugin
^---------------^ SC2164 (warning): Use 'cd ... || exit' or 'cd ... || return' in case cd fails.
^-----^ SC2086 (info): Double quote to prevent globbing and word splitting.
Did you mean:
echo '' && cd crates/"$plugin" || exit
In install-all.sh line 14:
NU_PLUGINS=(
^-- SC3030 (warning): In POSIX sh, arrays are undefined.
In install-all.sh line 22:
for plugin in "${NU_PLUGINS[@]}"
^--------------^ SC3054 (warning): In POSIX sh, array references are undefined.
In install-all.sh line 28:
cd crates/$plugin && cargo install --path . && cd ../../
^-----^ SC2086 (info): Double quote to prevent globbing and word splitting.
Did you mean:
cd crates/"$plugin" && cargo install --path . && cd ../../
In uninstall-all.sh line 8:
NU_PLUGINS=(
^-- SC3030 (warning): In POSIX sh, arrays are undefined.
In uninstall-all.sh line 16:
for plugin in "${NU_PLUGINS[@]}"
^--------------^ SC3054 (warning): In POSIX sh, array references are undefined.
In uninstall-all.sh line 18:
cargo uninstall $plugin
^-----^ SC2086 (info): Double quote to prevent globbing and word splitting.
Did you mean:
cargo uninstall "$plugin"
For more information:
https://www.shellcheck.net/wiki/SC2164 -- Use 'cd ... || exit' or 'cd ... |...
https://www.shellcheck.net/wiki/SC3030 -- In POSIX sh, arrays are undefined.
https://www.shellcheck.net/wiki/SC3054 -- In POSIX sh, array references are...
```
To fix SC2164 I used `set -euo pipefail` as per this Julia Evans suggestion:
