scripts: west: commands: shields: add cmd for listing supported shields

Add "west shields" command for listing supported shields.

Signed-off-by: Henrik Brix Andersen <hebad@vestas.com>

scripts/west-commands.yml

@@ -10,6 +10,11 @@ west-commands:
       - name: boards
         class: Boards
         help: display information about supported boards
+  - file: scripts/west_commands/shields.py
+    commands:
+      - name: shields
+        class: Shields
+        help: display list of supported shields
   - file: scripts/west_commands/build.py
     commands:
       - name: build

scripts/west_commands/shields.py

@@ -0,0 +1,86 @@
+# Copyright (c) 2024 Vestas Wind Systems A/S
+# Copyright (c) 2019 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: Apache-2.0
+
+import argparse
+import os
+from pathlib import Path
+import re
+import sys
+import textwrap
+
+from west import log
+from west.commands import WestCommand
+
+from zephyr_ext_common import ZEPHYR_BASE
+
+sys.path.append(os.fspath(Path(__file__).parent.parent))
+import list_shields
+import zephyr_module
+
+class Shields(WestCommand):
+
+    def __init__(self):
+        super().__init__(
+            'shields',
+            # Keep this in sync with the string in west-commands.yml.
+            'display list of supported shield',
+            'Display supported shields',
+            accepts_unknown_args=False)
+
+    def do_add_parser(self, parser_adder):
+        default_fmt = '{name}'
+        parser = parser_adder.add_parser(
+            self.name,
+            help=self.help,
+            formatter_class=argparse.RawDescriptionHelpFormatter,
+            description=self.description,
+            epilog=textwrap.dedent(f'''\
+            FORMAT STRINGS
+            --------------
+
+            Shields are listed using a Python 3 format string. Arguments
+            to the format string are accessed by name.
+
+            The default format string is:
+
+            "{default_fmt}"
+
+            The following arguments are available:
+
+            - name: shield name
+            - dir: directory that contains the shield definition
+            '''))
+
+        # Remember to update west-completion.bash if you add or remove
+        # flags
+        parser.add_argument('-f', '--format', default=default_fmt,
+                            help='''Format string to use to list each shield;
+                                    see FORMAT STRINGS below.''')
+        parser.add_argument('-n', '--name', dest='name_re',
+                            help='''a regular expression; only shields whose
+                            names match NAME_RE will be listed''')
+        list_shields.add_args(parser)
+
+        return parser
+
+    def do_run(self, args, _):
+        if args.name_re is not None:
+            name_re = re.compile(args.name_re)
+        else:
+            name_re = None
+
+        modules_board_roots = [ZEPHYR_BASE]
+
+        for module in zephyr_module.parse_modules(ZEPHYR_BASE, self.manifest):
+            board_root = module.meta.get('build', {}).get('settings', {}).get('board_root')
+            if board_root is not None:
+                modules_board_roots.append(Path(module.project) / board_root)
+
+        args.board_roots += modules_board_roots
+
+        for shield in list_shields.find_shields(args):
+            if name_re is not None and not name_re.search(shield.name):
+                continue
+            log.inf(args.format.format(name=shield.name, dir=shield.dir))