Subject: Re: [PATCH v2 3/3] ci: install python on ubuntu

From: Ævar Arnfjörð Bjarmason <[email-masked]>
Date: Thu, 24 Nov 2022 12:02:17 +0100

On Thu, Nov 24 2022, Jiang Xin wrote:

> From: Jiang Xin <[email-masked]>
>
> Python is missing from the default ubuntu-22.04 runner image, which
> prevent git-p4 from working. To install python on ubuntu, we need to
> provide correct package name:
>
>  * On Ubuntu 18.04 (bionic), "/usr/bin/python2" is provided by the
>    "python" package, and "/usr/bin/python3" is provided by the "python3"
>    package.
>
>  * On Ubuntu 20.04 (focal) and above, "/usr/bin/python2" is provided by
>    the "python2" package which has a different name from bionic, and
>    "/usr/bin/python3" is provided by "python3".
>
> Since the "ubuntu-latest" runner image has a higher version, so its safe
> to use "python2" or "python3" package name.
>
> Signed-off-by: Jiang Xin <[email-masked]>
> ---
>  ci/install-dependencies.sh | 2 +-
>  ci/lib.sh                  | 2 ++
>  2 files changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/ci/install-dependencies.sh b/ci/install-dependencies.sh
> index 291e49bdde..e28d93a154 100755
> --- a/ci/install-dependencies.sh
> +++ b/ci/install-dependencies.sh
> @@ -15,7 +15,7 @@ case "$runs_on_os" in
>  ubuntu)
>  	sudo apt-get -q update
>  	sudo apt-get -q -y install language-pack-is libsvn-perl apache2 \
> -		$UBUNTU_COMMON_PKGS $CC_PACKAGE
> +		$UBUNTU_COMMON_PKGS $CC_PACKAGE $PYTHON_PACKAGE
>  	mkdir --parents "$P4_PATH"
>  	pushd "$P4_PATH"
>  		wget --quiet "$P4WHENCE/bin.linux26x86_64/p4d"
> diff --git a/ci/lib.sh b/ci/lib.sh
> index a618d66b81..ebe702e0ea 100755
> --- a/ci/lib.sh
> +++ b/ci/lib.sh
> @@ -235,8 +235,10 @@ ubuntu)
>  	if [ "$jobname" = linux-gcc ]
>  	then
>  		MAKEFLAGS="$MAKEFLAGS PYTHON_PATH=/usr/bin/python3"
> +		PYTHON_PACKAGE=python3
>  	else
>  		MAKEFLAGS="$MAKEFLAGS PYTHON_PATH=/usr/bin/python2"
> +		PYTHON_PACKAGE=python2
>  	fi

Let's not copy/paste and repeat ourselves here for no reason. Part of
this is pre-existing, but if you just re-arrange these variable decls
you can do this instead:

	PYTHON_PACKAGE=python2
	if test "$jobname" = linux-gcc
	then
		PYTHON_PACKAGE=python3
	fi
	MAKEFLAGS="$MAKEFLAGS PYTHON_PATH=/usr/bin/${PYTHON_PACKAGE}"

Even if you don't factor out the "else" like that (which I think would
be OK to do while-we'er-at-it) this should be changed so that the
"PYTHON_PACKAGE" comes before "MAKEFLAGS" in the two if/else branches
here, so we can then use the variable.