The shell completion scripts included in the [package `python-poetry`](https://archlinux.org/packages/community/any/python-poetry/) are empty:

```
$ wc --bytes -- /usr/share/bash-completion/completions/poetry /usr/share/fish/vendor_completions.d/poetry.fish /usr/share/zsh/site-functions/_poetry
0 /usr/share/bash-completion/completions/poetry
0 /usr/share/fish/vendor_completions.d/poetry.fish
0 /usr/share/zsh/site-functions/_poetry
0 total
```

The [`PKGBUILD`](https://github.com/archlinux/svntogit-community/blob/packages/python-poetry/trunk/PKGBUILD) invokes a [Python script](https://github.com/archlinux/svntogit-community/blob/packages/python-poetry/trunk/poetry-completions-generator) to generate them:

```
./poetry-completions-generator completions bash |
sed "#$srcdir#d" |
install -Dm644 /dev/stdin "$pkgdir/usr/share/bash-completion/completions/poetry"
./poetry-completions-generator completions zsh |
sed "#$srcdir#d" |
install -Dm644 /dev/stdin "$pkgdir/usr/share/zsh/site-functions/_poetry"
./poetry-completions-generator completions fish |
install -Dm644 /dev/stdin "$pkgdir/usr/share/fish/vendor_completions.d/poetry.fish"
```

```
import sys
from poetry.console import main

sys.argv = ['poetry', 'completions', sys.argv.pop()]

main()
```

The Python script fails because the function `main` is no longer in the module `poetry.console`:

```
$ python
Python 3.10.9 (main, Dec 19 2022, 17:35:49) [GCC 12.2.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys
>>> from poetry.console import main
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ImportError: cannot import name 'main' from 'poetry.console' (/usr/lib/python3.10/site-packages/poetry/console/__init__.py)
>>> quit()
```

The function `main` was moved with [upstream git commit `a8d02ef59f60c001458f27b7cb2557a346cfb6b6`](https://github.com/python-poetry/poetry/commit/a8d02ef59f60c001458f27b7cb2557a346cfb6b6#diff-40d2f9aa8026c63507b86318987a0b426c2d529c3cc3b26ab09871980b44c7cb) in January 2021 to the module `poetry.console.application`. Adjusting the `import` statement solves the issue:

```
$ python -- - bash
Python 3.10.9 (main, Dec 19 2022, 17:35:49) [GCC 12.2.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys
>>> from poetry.console.application import main
>>> sys.argv = ['poetry', 'completions', sys.argv.pop()]
>>> main()
_poetry_d35cb51f6b8ed5a1_complete()
{
local cur script coms opts com
COMPREPLY=()
_get_comp_words_by_ref -n : cur words

...
```

To incorporate this fix, apply the patch `1-fix-shell-completion-script-generation.patch` attached to this bug report.

Building the package succeeds despite the Python script's failure because Bash is ignoring the Python script's exit status:

> The exit status of a pipeline is the exit status of the last command in the pipeline, unless the `pipefail` option is enabled (see [The Set Builtin](https://www.gnu.org/software/bash/manual/bash.html#The-Set-Builtin)).
> If `pipefail` is enabled, the pipeline’s return status is the value of the last (rightmost) command to exit with a non-zero status, or zero if all commands exit successfully.

To make the package build process fail and prevent this issue if/when upstream changes the location (or name, or semantics,…) of the function `main` again, we can enable the shell option `pipefail` in the relevant section of the `PKGBUILD`. To do so, apply the patch `2-fail-if-shell-completion-script-generation-fails.patch` attached to this bug report.