Generate bash-completion and zsh-completion using shtab

.gitlab-ci.yml

@@ -51,6 +51,7 @@ pre_commit:
 build_stable:
   variables:
     JOB_DEPS: argparse-manpage
+              python3-shtab
   extends:
     - .install-deps
   script:

meson.build

@@ -67,6 +67,18 @@ address_sanitizer = get_option('b_sanitize') == 'address' or \
   get_option('b_sanitize') == 'address,undefined' or \
   get_option('b_sanitize') == 'leak'
 
+python = import('python')
+python3 = python.find_installation('python3')
+
+have_shtab = run_command(
+  [python3, '-c', 'import shtab'], check: false).returncode() == 0
+if not have_shtab
+  warning('''python3-shtab not found''')
+endif
+
+bashcomp = dependency('bash-completion', required: get_option('bashcomp').disable_auto_if(not have_shtab))
+zshcomp = have_shtab and get_option('zshcomp') != ''
+
 subdir('src')
 subdir('data')
 
@@ -80,6 +92,9 @@ if get_option('gtk_doc')
   subdir('docs')
 endif
 
+python = import('python')
+python3 = python.find_installation('python3')
+
 if get_option('tests')
   # Python 3 required modules
   python3_required_modules = ['dbusmock', 'gi']
@@ -89,8 +104,6 @@ if get_option('tests')
     'UMockdev': '1.0',
   }
 
-  python = import('python')
-  python3 = python.find_installation('python3')
   foreach p : python3_required_modules
     # Source: https://docs.python.org/3/library/importlib.html#checking-if-a-module-can-be-imported
     script = 'import importlib.util; import sys; exit(1) if importlib.util.find_spec(\''+ p +'\') is None else exit(0)'

meson_options.txt

@@ -18,3 +18,11 @@ option('manpage',
        description: 'generate powerprofilesctl man page',
        type: 'feature',
        value: 'auto')
+option('bashcomp',
+       description: 'generate bash completion',
+       type: 'feature',
+       value: 'auto')
+option('zshcomp',
+       description: 'path for zsh completion file',
+       type: 'string',
+       value: '')

src/meson.build

@@ -146,3 +146,35 @@ if argparse_manpage.found()
     output: 'powerprofilesctl.1',
   ))
 endif
+
+generate_completion = [python3, powerprofilesctl, '--print-completion']
+if bashcomp.found()
+  completions_dir = bashcomp.get_variable(pkgconfig: 'completionsdir',
+    pkgconfig_define: bashcomp.version().version_compare('>= 2.10') ?
+      ['datadir', get_option('datadir')] : ['prefix', prefix],
+  )
+
+  custom_target('bash-completion',
+    output: 'powerprofilesctl',
+    command: [
+      generate_completion,
+      'bash',
+    ],
+    capture: true,
+    install: true,
+    install_dir: completions_dir,
+  )
+endif
+
+if zshcomp
+  custom_target('zsh-completion',
+    output: '_powerprofilesctl',
+    command: [
+      generate_completion,
+      'zsh',
+    ],
+    capture: true,
+    install: true,
+    install_dir: get_option('zshcomp'),
+  )
+endif

src/powerprofilesctl

@@ -190,6 +190,13 @@ def get_parser():
     )
     parser_version.set_defaults(func=_version)
 
+    try:
+        import shtab  # pylint: disable=import-outside-toplevel
+
+        shtab.add_argument_to(parser, ["-s", "--print-completion"])  # magic!
+    except ImportError:
+        pass
+
     return parser