Subcommands listed in `tahoe --help` are not grouped by function

[exarkun]

The implementation of the tahoe CLI carefully arranges its subcommands into groups for ease of comprehension by users.

Since Twisted 17.9, subcommands are sorted alphabetically and the supplied order is disregarded.

tahoe --help now lists subcommands like this:

Commands:

(Administration)

(Controlling a node)

(Debugging)

(Grid Management)

(Using the file store)
    add-alias                    Add a new alias cap.
    admin                        admin subcommands: use 'tahoe admin' for a list
    backup                       Make target dir look like local dir.
    check                        Check a single file or directory.
    cp                           Copy one or more files or directories.
    create-alias                 Create a new alias cap.
    create-client                Create a client node (with storage initially
                                 disabled).
    create-introducer            Create an introducer node.
    create-node                  Create a node that acts as a client, server or
                                 both.
    create-stats-gatherer        Create a stats-gatherer service.
    daemonize                    run a node in the background
    debug                        debug subcommands: use 'tahoe debug' for a
                                 list.
    deep-check                   Check all files/directories reachable from a
                                 starting point.
    get                          Retrieve a file from the grid.
    invite                       Invite a new node to this grid
    list-aliases                 List all alias caps.
    ln                           Make an additional link to an existing file or
                                 directory.
    ls                           List a directory.
    magic-folder                 Magic Folder subcommands: use 'tahoe magic-
                                 folder' for a list.
    manifest                     List all files/directories in a subtree.
    mkdir                        Create a new directory.
    mv                           Move a file within the grid.
    put                          Upload a file into the grid.
    restart                      restart a node
    rm                           Unlink a file or directory on the grid (same as
                                 unlink).
    run                          run a node without daemonizing
    start                        start a node in the background and confirm it
                                 started
    stats                        Print statistics about all files/directories in
                                 a subtree.
    status                       Various status information.
    stop                         stop a node
    unlink                       Unlink a file or directory on the grid.
    webopen                      Open a web browser to a grid file or directory.

Notice how the category separators now all appear at the top (which presumably makes no sense to people who don't know what this used to look like and is useless in any case).

The Twisted change which broke the old behavior is ​https://twistedmatrix.com/trac/ticket/9133

[exarkun]

​https://github.com/tahoe-lafs/tahoe-lafs/pull/555

[GitHub <noreply@…>]

In 3c68f58/trunk:

Merge pull request #555 from tahoe-lafs/2976.help-output-groups

Remove the attempt at grouping the subcommands.

Fixes: ticket:2976