Generate & install completion scripts in build system

The previous commit added a means to generating the completion scripts
and this one plugs that into the build system.

A new build option 'install_completions' has been introduced. Set to
'True' by default.

Completions for bash and fish use pkg-config for getting the preferred
install locations for the completions. If the packages are not
available, fallbacks are in-place.

The 'completion' subdir has been kept to work around the ideology of
Meson that does not allow creating/outputing files in subdirectories nor
using the output of custom_target() in install_data().

https://github.com/containers/toolbox/pull/840

README.md

@@ -43,3 +43,4 @@ database, etc..
 See our guides on
 [installing & getting started](https://containertoolbx.org/install/) with
 Toolbox and [Linux distro support](https://containertoolbx.org/distros/).
+

completion/bash/toolbox

@@ -1,100 +0,0 @@
-# Check for bash
-[ -z "$BASH_VERSION" ] && return
-
-__toolbox_containers() {
-  toolbox list -c 2>/dev/null | tail -n +2 2>/dev/null | cut -d " " -f 3 2>/dev/null
-}
-
-__toolbox_distros() {
-  echo "fedora"
-  echo "rhel"
-}
-
-__toolbox_images() {
-  toolbox list -i 2>/dev/null | tail -n +2 2>/dev/null | cut -d " " -f 3 2>/dev/null
-}
-
-__toolbox() {
-  local MIN_VERSION=32
-  local RAWHIDE_VERSION=34
-
-  local commands="create enter help init-container list rm rmi run"
-  local global_options="--assumeyes --help --log-level --log-podman"
-  local log_levels="debug info warn error fatal panic"
-
-  declare -A options
-  local options=([create]="--distro --image --release" \
-                 [enter]="--distro --release" \
-                 [help]="$commands" \
-                 [init-container]="--home --home-link --monitor-host --shell --uid --user" \
-		 [list]="--containers --images" \
-		 [rm]="--all --force" \
-		 [rmi]="--all --force" \
-		 [run]="--container --distro --release")
-
-  _init_completion -s || return
-
-  if [ "${COMP_CWORD}" -eq 1 ]; then
-    mapfile -t COMPREPLY < <(compgen -W "$global_options $commands" -- "$2")
-    return 0
-  fi
-
-  # If a global option is mentioned, don't mention it anymore
-  for option in $global_options; do
-    if [[ "${COMP_LINE}" =~ "$option" ]]; then
-      global_options="${global_options/$option}"
-    fi
-  done
-
-  # If a command is mentioned, don't mention any more commands
-  local command
-  for cmd in $commands; do
-    if [[ "${COMP_LINE}" =~ "$cmd" ]]; then
-      commands=""
-      command="$cmd"
-    fi
-  done
-
-  case "$prev" in
-    --assumeyes | -y | --help | -h | --verbose | -v | --log-podman)
-      mapfile -t COMPREPLY < <(compgen -W "$global_options $commands" -- "$2")
-      return 0
-      ;;
-    --container | -c)
-      mapfile -t COMPREPLY < <(compgen -W "$(__toolbox_containers)" -- "$2")
-      return 0
-      ;;
-    --distro | -d)
-      mapfile -t COMPREPLY < <(compgen -W "$(__toolbox_distros)" -- "$2")
-      return 0
-      ;;
-    --image | -i)
-      mapfile -t COMPREPLY < <(compgen -W "$(__toolbox_images)" -- "$2")
-      return 0
-      ;;
-    --release | -r)
-      mapfile -t COMPREPLY < <(compgen -W "$(seq $MIN_VERSION $RAWHIDE_VERSION)" -- "$2")
-      return 0
-      ;;
-    --log-level)
-      mapfile -t COMPREPLY < <(compgen -W "$log_levels" -- "$2")
-      return 0
-      ;;
-  esac
-
-  local extra_comps
-  case "$command" in
-    rm | enter)
-      extra_comps="$(__toolbox_containers)"
-      ;;&
-    rmi)
-      extra_comps="$(__toolbox_images)"
-      ;;&
-    *)
-      mapfile -t COMPREPLY < <(compgen -W "${options[$command]} $extra_comps" -- "$2")
-      return 0;
-      ;;
-  esac
-}
-
-complete -F __toolbox toolbox

completion/generate_completions.py

@@ -0,0 +1,41 @@
+#!/usr/bin/env python3
+#
+# Copyright © 2022 Ondřej Míchal
+# Copyright © 2022 Red Hat Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+import os
+import subprocess
+import sys
+
+if len(sys.argv) != 3:
+    print('{}: wrong arguments'.format(sys.argv[0]), file=sys.stderr)
+    print('Usage: {} [SOURCE DIR] [COMPLETION TYPE]'.format(sys.argv[0]), file=sys.stderr)
+    print()
+    print("SOURCE DIR is path to the Toolbox Go source code")
+    print("COMPLETION TYPE is either 'bash', 'zsh' or 'fish'")
+    sys.exit(1)
+
+source_dir = sys.argv[1]
+completion_type = sys.argv[2]
+
+try:
+    os.chdir(source_dir)
+    output = subprocess.run(['go', 'run', '.', 'completion', completion_type], check=True)
+except subprocess.CalledProcessError as e:
+    print('{}: go run returned non-zero exit status {}'.format(sys.argv[0], e.returncode), file=sys.stderr)
+    sys.exit(e.returncode)
+
+sys.exit(0)

completion/meson.build

@@ -0,0 +1,36 @@
+generate_completions_program = find_program('generate_completions.py')
+
+if bash_completion.found()
+  bash_comp_dir = bash_completion.get_pkgconfig_variable('completionsdir')
+else
+  bash_comp_dir = get_option('datadir') / 'bash-completion' / 'completions'
+  message('bash-completion not found: using', get_option('prefix') / bash_comp_dir, 'as a falback install directory')
+endif
+
+if fish.found()
+  fish_comp_dir = fish.get_pkgconfig_variable('completionsdir')
+else
+  fish_comp_dir = get_option('datadir') / 'fish' / 'completions'
+  message('fish not found: using', get_option('prefix') / fish_comp_dir, 'as a fallback install directory')
+endif
+
+completion_bash = custom_target('bash-completion',
+  capture: true,
+  command: [generate_completions_program, meson.global_source_root() / 'src', 'bash'],
+  install: true,
+  install_dir: bash_comp_dir,
+  output: 'toolbox')
+
+completion_zsh = custom_target('zsh-completion',
+  capture: true,
+  command: [generate_completions_program, meson.global_source_root() / 'src', 'zsh'],
+  install: true,
+  install_dir: get_option('datadir') / 'zsh' / 'site_functions',
+  output: '_toolbox')
+
+completion_fish = custom_target('fish-completion',
+  capture: true,
+  command: [generate_completions_program, meson.global_source_root() / 'src', 'fish'],
+  install: true,
+  install_dir: fish_comp_dir,
+  output: 'toolbox.fish')

meson.build

@@ -19,6 +19,7 @@ shellcheck = find_program('shellcheck', required: false)
 skopeo = find_program('skopeo', required: false)
 
 bash_completion = dependency('bash-completion', required: false)
+fish = dependency('fish', required: false)
 
 migration_path_for_coreos_toolbox = get_option('migration_path_for_coreos_toolbox')
 profiledir = get_option('profile_dir')
@@ -32,13 +33,6 @@ if tmpfilesdir == '' or not fs.exists('/run/.containerenv')
   endif
 endif
 
-if bash_completion.found()
-  install_data(
-    'completion/bash/toolbox',
-    install_dir: bash_completion.get_variable(pkgconfig: 'completionsdir')
-  )
-endif
-
 if not skopeo.found()
     message('Running system tests requires Skopeo for OCI image manipulation.')
 endif
@@ -70,5 +64,8 @@ subdir('data')
 subdir('doc')
 subdir('profile.d')
 subdir('src')
+if get_option('install_completions')
+  subdir('completion')
+endif
 
 meson.add_install_script('meson_post_install.py')

meson_options.txt

@@ -17,3 +17,10 @@ option(
   description: 'Directory for system-wide tmpfiles.d(5) files',
   type: 'string',
 )
+
+option(
+  'install_completions',
+  description: 'Install bash, zsh and fish command completions',
+  type: 'boolean',
+  value: true,
+)