bin/python-venv: detect python version change

The venv only works for a specific python version; when updating python,
the venv needs to be regenerated.

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/26354>

1 files changed, 17 insertions, 0 deletions

diff --git a/bin/python-venv.sh b/bin/python-venv.sh
index 2c4f6dccdbe..b6cf7fd9f5b 100755
--- a/bin/python-venv.sh
+++ b/bin/python-venv.sh
@@ -7,11 +7,28 @@ shift
 venv_dir="$(dirname "$requirements_file")"/.venv
 readonly venv_dir
 readonly venv_req=$venv_dir/requirements.txt
+readonly venv_python_version=$venv_dir/python-version.txt
+
+if [ -d "$venv_dir" ] && [ ! -r "$venv_python_version" ]
+then
+  echo "Python environment predates Python version checks."
+  echo "It might be invalid and needs to be regenerated."
+  rm -rf "$venv_dir"
+elif ! cmp --quiet <(python --version) "$venv_python_version"
+then
+  old=$(cat "$venv_python_version")
+  new=$(python --version)
+  echo "Python version has changed ($old -> $new)."
+  echo "Python environment needs to be regenerated."
+  unset old new
+  rm -rf "$venv_dir"
+fi
 
 if ! [ -r "$venv_dir/bin/activate" ]
 then
   echo "Creating Python environment..."
   python -m venv "$venv_dir"
+  python --version > "$venv_python_version"
 fi
 
 # shellcheck disable=1091