install-prerequisites: add an option for optional dependencies (#3560)

plugins/python-build/bin/pyenv-install-prerequisites

@@ -2,13 +2,16 @@
 #
 # Summary: Install Python build prerequisites on Debian-based systems
 #
-# Usage: pyenv install-prerequisites
+# Usage: pyenv install-prerequisites [-a|--all]
+#
+#   -a/--all       Also install optional dependencies (for rarely used modules)
 #
 set -e
 [ -n "$PYENV_DEBUG" ] && set -x
 
 # Provide pyenv completions
 if [ "$1" = "--complete" ]; then
+  echo --all
   exit
 fi
 
@@ -17,11 +20,22 @@ usage() {
   [ -z "$1" ] || exit "$1"
 }
 
-if [ "$1" = "-h" ] || [ "$1" = "--help" ]; then
-  usage 0
-fi
+all=
 
-[ "$#" -eq 0 ] || usage 1 >&2
+while (($#)); do
+  case "$1" in
+    -h|--help)
+      usage 0
+      ;;
+    -a|--all)
+      all=1
+      ;;
+    *)
+      usage 1 >&2
+      ;;
+  esac
+  shift
+done
 
 if ! command -v apt-get >/dev/null; then
   echo "pyenv: installing build prerequisites is not supported on this system" >&2
@@ -33,6 +47,9 @@ prerequisites=(
   libsqlite3-dev curl git llvm libncurses5-dev libncursesw5-dev xz-utils
   tk-dev libxml2-dev libxmlsec1-dev libffi-dev liblzma-dev libzstd-dev
 )
+optional=(
+  libgdbm-dev
+)
 
 if [ "$(id -u)" -eq 0 ]; then
   apt_get=(apt-get)
@@ -44,4 +61,4 @@ else
 fi
 
 "${apt_get[@]}" update -q
-"${apt_get[@]}" install -yq "${prerequisites[@]}"
+"${apt_get[@]}" install -yq "${prerequisites[@]}" ${all:+"${optional[@]}"}

plugins/python-build/test/install-prerequisites.bats

@@ -4,18 +4,21 @@ load test_helper
 
 _setup() {
   prerequisites="make build-essential libssl-dev zlib1g-dev libbz2-dev \
-libreadline-dev libsqlite3-dev curl git llvm libncurses5-dev \
-libncursesw5-dev xz-utils tk-dev libxml2-dev libxmlsec1-dev libffi-dev \
-liblzma-dev libzstd-dev"
+  libreadline-dev libsqlite3-dev curl git llvm libncurses5-dev \
+  libncursesw5-dev xz-utils tk-dev libxml2-dev libxmlsec1-dev libffi-dev \
+  liblzma-dev libzstd-dev"
+  
+  optional="libgdbm-dev"
 }
 
-@test "completion does not install packages" {
+@test "completions" {
   stub apt-get
 
-  PATH="${BATS_TEST_DIRNAME}/../../../libexec:$PATH" \
-    run pyenv completions install-prerequisites
+  run pyenv-install-prerequisites --complete
 
-  assert_success "--help"
+  assert_success <<!
+--all
+!
   unstub apt-get
 }
 
@@ -28,7 +31,7 @@ liblzma-dev libzstd-dev"
   unstub pyenv-help
 }
 
-@test "rejects arguments" {
+@test "invalid arguments" {
   stub pyenv-help 'install-prerequisites : echo "Usage: pyenv install-prerequisites"'
 
   run pyenv-install-prerequisites unexpected
@@ -50,6 +53,19 @@ liblzma-dev libzstd-dev"
   unstub id
 }
 
+@test "installs optional prerequisites with --all" {
+  stub id '-u : echo 0'
+  stub apt-get \
+    'update -q : true' \
+    "install -yq ${prerequisites} ${optional} : true"
+
+  run pyenv-install-prerequisites --all
+
+  assert_success
+  unstub apt-get
+  unstub id
+}
+
 @test "uses sudo when not running as root" {
   stub id '-u : echo 1000'
   stub apt-get