tools/mpremote: Add new 'fs tree' command.

Add `mpremote fs tree` command to show a tree of the device's files.  It:
- Shows a treeview from current path or specified path.
- Uses the graph chars ("├── ", "└── ") (not configurable).
- Has the options:
    -v/--verbose adds the serial device name to the top of the tree
    -s/--size add a size to the files
    -h/--human add a human readable size to the files

Signed-off-by: Jos Verlinde <jos_verlinde@hotmail.com>

tools/mpremote/mpremote/commands.py

@@ -334,6 +334,49 @@ def do_filesystem_recursive_rm(state, path, args):
             print(f"removed: '{path}'")
 
 
+def human_size(size, decimals=1):
+    for unit in ['B', 'K', 'M', 'G', 'T']:
+        if size < 1024.0 or unit == 'T':
+            break
+        size /= 1024.0
+    return f"{size:.{decimals}f}{unit}" if unit != 'B' else f"{int(size)}"
+
+
+def do_filesystem_tree(state, path, args):
+    """Print a tree of the device's filesystem starting at path."""
+    connectors = ("├── ", "└── ")
+
+    def _tree_recursive(path, prefix=""):
+        entries = state.transport.fs_listdir(path)
+        entries.sort(key=lambda e: e.name)
+        for i, entry in enumerate(entries):
+            connector = connectors[1] if i == len(entries) - 1 else connectors[0]
+            is_dir = entry.st_mode & 0x4000  # Directory
+            size_str = ""
+            # most MicroPython filesystems don't support st_size on directories, reduce clutter
+            if entry.st_size > 0 or not is_dir:
+                if args.size:
+                    size_str = f"[{entry.st_size:>9}]  "
+                elif args.human:
+                    size_str = f"[{human_size(entry.st_size):>6}]  "
+            print(f"{prefix}{connector}{size_str}{entry.name}")
+            if is_dir:
+                _tree_recursive(
+                    _remote_path_join(path, entry.name),
+                    prefix + ("    " if i == len(entries) - 1 else "│   "),
+                )
+
+    if not path or path == ".":
+        path = state.transport.exec("import os;print(os.getcwd())").strip().decode("utf-8")
+    if not (path == "." or state.transport.fs_isdir(path)):
+        raise CommandError(f"tree: '{path}' is not a directory")
+    if args.verbose:
+        print(f":{path} on {state.transport.device_name}")
+    else:
+        print(f":{path}")
+    _tree_recursive(path)
+
+
 def do_filesystem(state, args):
     state.ensure_raw_repl()
     state.did_action()
@@ -361,8 +404,8 @@ def do_filesystem(state, args):
         # leading ':' if the user included them.
         paths = [path[1:] if path.startswith(":") else path for path in paths]
 
-    # ls implicitly lists the cwd.
-    if command == "ls" and not paths:
+    # ls and tree implicitly lists the cwd.
+    if command in ("ls", "tree") and not paths:
         paths = [""]
 
     try:
@@ -404,6 +447,8 @@ def do_filesystem(state, args):
                     )
                 else:
                     do_filesystem_cp(state, path, cp_dest, len(paths) > 1, not args.force)
+            elif command == "tree":
+                do_filesystem_tree(state, path, args)
     except OSError as er:
         raise CommandError("{}: {}: {}.".format(command, er.strerror, os.strerror(er.errno)))
     except TransportError as er:

tools/mpremote/mpremote/main.py

@@ -181,7 +181,11 @@ def argparse_rtc():
 
 
 def argparse_filesystem():
-    cmd_parser = argparse.ArgumentParser(description="execute filesystem commands on the device")
+    cmd_parser = argparse.ArgumentParser(
+        description="execute filesystem commands on the device",
+        add_help=False,
+    )
+    cmd_parser.add_argument("--help", action="help", help="show this help message and exit")
     _bool_flag(cmd_parser, "recursive", "r", False, "recursive (for cp and rm commands)")
     _bool_flag(
         cmd_parser,
@@ -197,10 +201,26 @@ def argparse_filesystem():
         None,
         "enable verbose output (defaults to True for all commands except cat)",
     )
+    size_group = cmd_parser.add_mutually_exclusive_group()
+    size_group.add_argument(
+        "--size",
+        "-s",
+        default=False,
+        action="store_true",
+        help="show file size in bytes(tree command only)",
+    )
+    size_group.add_argument(
+        "--human",
+        "-h",
+        default=False,
+        action="store_true",
+        help="show file size in a more human readable way (tree command only)",
+    )
+
     cmd_parser.add_argument(
         "command",
         nargs=1,
-        help="filesystem command (e.g. cat, cp, sha256sum, ls, rm, rmdir, touch)",
+        help="filesystem command (e.g. cat, cp, sha256sum, ls, rm, rmdir, touch, tree)",
     )
     cmd_parser.add_argument("path", nargs="+", help="local and remote paths")
     return cmd_parser
@@ -355,6 +375,7 @@ _BUILTIN_COMMAND_EXPANSIONS = {
     "rmdir": "fs rmdir",
     "sha256sum": "fs sha256sum",
     "touch": "fs touch",
+    "tree": "fs tree",
     # Disk used/free.
     "df": [
         "exec",
@@ -552,8 +573,13 @@ def main():
                 command_args = remaining_args
                 extra_args = []
 
-            # Special case: "fs ls" allowed have no path specified.
-            if cmd == "fs" and len(command_args) == 1 and command_args[0] == "ls":
+            # Special case: "fs ls" and "fs tree" can have only options and no path specified.
+            if (
+                cmd == "fs"
+                and len(command_args) >= 1
+                and command_args[0] in ("ls", "tree")
+                and sum(1 for a in command_args if not a.startswith('-')) == 1
+            ):
                 command_args.append("")
 
             # Use the command-specific argument parser.