scripts: zephyr_flash_debug: add 'runners' command

This just prints the available runner classes.

Signed-off-by: Marti Bolivar <marti@opensourcefoundries.com>

scripts/support/zephyr_flash_debug.py

@@ -21,6 +21,11 @@ import sys
 from runner.core import ZephyrBinaryRunner
 
 
+def print_runners_handler(args):
+    for cls in ZephyrBinaryRunner.get_runners():
+        print(cls.name())
+
+
 def runner_handler(cls, args):
     runner = cls.create_from_args(args)
     # This relies on ZephyrBinaryRunner.add_parser() having command as
@@ -47,18 +52,30 @@ def main():
     # $ZEPHYR_BASE/.../SCRIPT.py [-v|--verbose] RUNNER [--runner-options]
     #
     # Note that --verbose comes *before* RUNNER, not after!
+    #
+    # Other commands (for now just the "runners" command, which prints
+    # the available runners) are handled the same way:
+    #
+    # $ZEPHYR_BASE/.../SCRIPT.py runners
     top_parser = argparse.ArgumentParser()
     top_parser.add_argument('-v', '--verbose',
                             default=False, action='store_true',
                             help='If set, enable verbose output.')
-    sub_parsers = top_parser.add_subparsers(dest='runner')
+    sub_parsers = top_parser.add_subparsers(dest='top_command')
+
+    # Handlers for each subcommand.
+    handlers = {}
+
+    # The 'runners' command just prints the runners. It takes no arguments.
+    sub_parsers.add_parser('runners')
+    handlers['runners'] = print_runners_handler
 
     # Add a sub-command for each runner. (It's a bit hackish for runners
     # to know about argparse, but it's good enough for now.)
-    handlers = {}
     for cls in ZephyrBinaryRunner.get_runners():
         if cls.name() in handlers:
-            print('Runner {} name is already a sub-command'.format(cls.name()),
+            print('Runner {} name is already a top-level command'.format(
+                      cls.name()),
                   file=sys.sterr)
             sys.exit(1)
         sub_parser = sub_parsers.add_parser(cls.name())
@@ -66,12 +83,13 @@ def main():
         handlers[cls.name()] = functools.partial(runner_handler, cls)
 
     args = top_parser.parse_args()
-    if args.runner is None:
-        runners = ', '.join(handlers.keys())
-        print('Missing runner; choices: {}'.format(runners), file=sys.stderr)
+    if args.top_command is None:
+        choices = ', '.join(handlers.keys())
+        print('Missing command or runner; choices: {}'.format(choices),
+              file=sys.stderr)
         sys.exit(1)
     try:
-        handlers[args.runner](args)
+        handlers[args.top_command](args)
     except Exception as e:
         print('Error: {}'.format(e), file=sys.stderr)
         raise