add support for 'config --list-paths'

added config command to list all config files and dropin files which are
currently considered by west.

Author: thorsten-klein

src/west/app/config.py

@@ -7,7 +7,7 @@
 import argparse
 
 from west.commands import CommandError, WestCommand
-from west.configuration import ConfigFile
+from west.configuration import ConfigFile, Configuration
 
 CONFIG_DESCRIPTION = '''\
 West configuration file handling.
@@ -74,13 +74,22 @@
 To delete <name> everywhere it's set, including the system file:
     west config -D <name>
 
-Additionally to the config file a dropin config directory is considered.
-The directory is named as the according config file, but with a '.d' suffix.
-As a result there are three levels for dropin config directories (local, global
-and system), whereby all '.conf' files from each dropin directory are loaded in
-alphabetical order.
+For each configuration type (local, global, and system), an additional
+drop-in directory is supported. This directory is named after the configuration
+file with a `.d` suffix.
+
+All files inside a drop-in directory must use `.conf` extension and are
+loaded in **alphabetical order**.
 For example:
     .west/config.d/basics.conf
+
+To list the configuration files that are loaded (both the main config file
+and all drop-ins) in the exact order they were applied (where later values
+override earlier ones):
+    west config --list-paths
+    west config --local --list-paths
+    west config --global --list-paths
+    west config --system --list-paths
 '''
 
 CONFIG_EPILOG = '''\
@@ -113,9 +122,12 @@ def do_add_parser(self, parser_adder):
             "action to perform (give at most one)"
         ).add_mutually_exclusive_group()
 
-        group.add_argument('-p', '--print-path', action='store_true',
-                           help='print file path from according west config'
-                           '(--system, --global, --local)')
+        group.add_argument('--print-path', action='store_true',
+                           help='print the file path from according west '
+                           'config (--local [default], --global, --system)')
+        group.add_argument('--list-paths', action='store_true',
+                           help='list all config files and dropin files that '
+                           'are currently considered by west config')
         group.add_argument('-l', '--list', action='store_true',
                            help='list all options and their values')
         group.add_argument('-d', '--delete', action='store_true',
@@ -151,7 +163,7 @@ def do_run(self, args, user_args):
         if args.list:
             if args.name:
                 self.parser.error('-l cannot be combined with name argument')
-        elif not args.name and not args.print_path:
+        elif not any([args.name, args.print_path, args.list_paths]):
             self.parser.error('missing argument name '
                               '(to list all options and values, use -l)')
         elif args.append:
@@ -160,6 +172,8 @@ def do_run(self, args, user_args):
 
         if args.print_path:
             self.print_path(args)
+        elif args.list_paths:
+            self.list_paths(args)
         elif args.list:
             self.list(args)
         elif delete:
@@ -176,6 +190,11 @@ def print_path(self, args):
         if config_path:
             print(config_path)
 
+    def list_paths(self, args):
+        config_paths = Configuration().get_paths(args.configfile or ALL)
+        for config_path in config_paths:
+            print(config_path)
+
     def list(self, args):
         what = args.configfile or ALL
         for option, value in self.config.items(configfile=what):

src/west/configuration.py

@@ -90,6 +90,12 @@ def __init__(self, path: Path):
                     self.dropin_paths.append(self.dropin_dir / conf)
         self._read()
 
+    def _paths(self) -> list[Path]:
+        ret = [p for p in self.dropin_paths]
+        if self.path:
+            ret.append(self.path)
+        return ret
+
     def _read(self):
         if self.path:
             self.cp.read(self.path, encoding='utf-8')
@@ -211,6 +217,16 @@ def get_path(self, configfile: ConfigFile = ConfigFile.LOCAL):
         elif configfile == ConfigFile.GLOBAL:
             return self._global_path
 
+    def get_paths(self, configfile: ConfigFile = ConfigFile.ALL):
+        ret = []
+        if self._global and configfile in [ConfigFile.GLOBAL, ConfigFile.ALL]:
+            ret += self._global._paths()
+        if self._system and configfile in [ConfigFile.SYSTEM, ConfigFile.ALL]:
+            ret += self._system._paths()
+        if self._local and configfile in [ConfigFile.LOCAL, ConfigFile.ALL]:
+            ret += self._local._paths()
+        return ret
+
     def get(self, option: str,
             default: str | None = None,
             configfile: ConfigFile = ConfigFile.ALL) -> str | None:

tests/test_config.py

@@ -93,6 +93,80 @@ def test_config_print_path():
     stdout = cmd('config --system --print-path')
     assert os.environ["WEST_CONFIG_SYSTEM"] == stdout.rstrip()
 
+    # print nothing if local config does not exist (exit code 0)
+    del os.environ['WEST_CONFIG_LOCAL']
+    stdout = cmd('config --local --print-path')
+    assert "" == stdout.rstrip()
+
+TEST_CASES_CONFIG_LIST_PATHS = [
+    # (flag, env_var)
+    ('--local', 'WEST_CONFIG_LOCAL'),
+    ('--system', 'WEST_CONFIG_SYSTEM'),
+    ('--global', 'WEST_CONFIG_GLOBAL'),
+]
+
+@pytest.mark.parametrize("test_case", TEST_CASES_CONFIG_LIST_PATHS)
+def test_config_list_paths(test_case):
+    flag, env_var = test_case
+
+    # no config is listed (since it does not exist)
+    stdout = cmd(f'config {flag} --list-paths')
+    assert '' == stdout.rstrip()
+
+    # create the config
+    cmd(f'config {flag} pytest.key val')
+
+    # check that the config is listed now
+    stdout = cmd(f'config {flag} --list-paths')
+    config_path = pathlib.Path(os.environ[env_var])
+    assert f'{config_path}' == stdout.rstrip()
+
+def test_config_list_paths_extended():
+    WEST_CONFIG_LOCAL = os.environ['WEST_CONFIG_LOCAL']
+    WEST_CONFIG_GLOBAL = os.environ['WEST_CONFIG_GLOBAL']
+    WEST_CONFIG_SYSTEM = os.environ['WEST_CONFIG_SYSTEM']
+
+    # create the configs
+    cmd('config --local pytest.key val')
+    cmd('config --global pytest.key val')
+    cmd('config --system pytest.key val')
+
+    # list the configs
+    stdout = cmd('config --list-paths')
+    assert stdout == textwrap.dedent(f'''\
+        {WEST_CONFIG_GLOBAL}
+        {WEST_CONFIG_SYSTEM}
+        {WEST_CONFIG_LOCAL}
+        ''')
+
+    # create some dropins files
+    dropin_files = [
+        pathlib.Path(WEST_CONFIG_GLOBAL + '.d') / 'a.conf',
+        pathlib.Path(WEST_CONFIG_GLOBAL + '.d') / 'z.conf',
+        pathlib.Path(WEST_CONFIG_SYSTEM + '.d') / 'a.conf',
+        pathlib.Path(WEST_CONFIG_SYSTEM + '.d') / 'z.conf',
+        pathlib.Path(WEST_CONFIG_LOCAL + '.d') / 'a.conf',
+        pathlib.Path(WEST_CONFIG_LOCAL + '.d') / 'z.conf',
+    ]
+    for dropin_file in dropin_files:
+        dropin_file.parent.mkdir(exist_ok=True)
+        dropin_file.touch()
+
+    # list the configs
+    stdout = cmd('config --list-paths')
+    assert stdout == textwrap.dedent(f'''\
+        {dropin_files[0]}
+        {dropin_files[1]}
+        {WEST_CONFIG_GLOBAL}
+        {dropin_files[2]}
+        {dropin_files[3]}
+        {WEST_CONFIG_SYSTEM}
+        {dropin_files[4]}
+        {dropin_files[5]}
+        {WEST_CONFIG_LOCAL}
+        ''')
+
+    # print nothing if local config does not exist (exit code 0)
     del os.environ['WEST_CONFIG_LOCAL']
     stdout = cmd('config --local --print-path')
     assert "" == stdout.rstrip()